Showing papers in "International Journal of Systematic and Evolutionary Microbiology in 2005"
TL;DR: It is proposed that strain YIM 31775(T) should be classified as representing a novel member of the family 'Oxalobacteraceae', for which the name Naxibacter alkalitolerans gen. nov., sp.
Abstract: A taxonomic study was performed on strain YIM 31775T, which was isolated from a soil sample collected from Yunnan Province, China. The isolate was chemo-organotrophic, aerobic and Gram-negative. Cells were short rods and motile, with one or more polar flagella. Growth temperature and pH ranged from 4 to 55 °C and 6·5 to 12·0, respectively; the optimum growth temperature and pH were 28–37 °C and 7·0–9·0, respectively. Q-8 was the predominant respiratory lipoquinone. The major fatty acids were C16 : 1 ω7c (42·4 %) and C16 : 0 (28·1 %). The DNA G+C content was 62·4±0·3 mol%. Phylogenetic analysis based on the 16S rRNA gene sequence indicated that strain YIM 31775T should be placed within the family ‘Oxalobacteraceae’, in which it formed a distinct lineage. Based on the high 16S rRNA gene sequence divergence and phenotypic characteristics, it is proposed that strain YIM 31775T should be classified as representing a novel member of the family ‘Oxalobacteraceae’, for which the name Naxibacter alkalitolerans gen. nov., sp. nov. is proposed. The type strain is YIM 31775T (=CCTCC AA 204003T=KCTC 12194T).
745 citations
TL;DR: Isolate PsJN(T) showed high 1-aminocyclopropane-1-carboxylate deaminase activity and is therefore able to lower the ethylene level in a developing or stressed plant and is considered to represent a single, novel species.
Abstract: A Gram-negative, non-sporulating, rod-shaped, motile bacterium, with a single polar flagellum, designated strain PsJN(T), was isolated from surface-sterilized onion roots. This isolate proved to be a highly effective plant-beneficial bacterium, and was able to establish rhizosphere and endophytic populations associated with various plants. Seven related strains were recovered from Dutch soils. Based on 16S rRNA gene sequence data, strain PsJN(T) and the Dutch strains were identified as representing a member of the genus Burkholderia, as they were closely related to Burkholderia fungorum (98.7 %) and Burkholderia phenazinium (98.5 %). Analysis of whole-cell protein profiles and DNA-DNA hybridization experiments confirmed that all eight strains belonged to a single species. Strain PsJN(T) had a DNA G+C content of 61.0 mol%. Only low levels of DNA-DNA hybridization to closely related species were found. Qualitative and quantitative differences in fatty acid composition between strain PsJN(T) and closely related species were identified. The predominant fatty acids in strain PsJN(T) were 16 : 0, 18 : 1omega7c and summed feature 3 (comprising 16 : 1omega7c and/or iso-15 : 0 2-OH). Isolate PsJN(T) showed high 1-aminocyclopropane-1-carboxylate deaminase activity and is therefore able to lower the ethylene level in a developing or stressed plant. Production of the quorum-sensing signal compound 3-hydroxy-C8-homoserine lactone was detected. Based on the results of this polyphasic taxonomic study, strain PsJN(T) and the seven Dutch isolates are considered to represent a single, novel species, for which the name Burkholderia phytofirmans sp. nov. is proposed. The type strain is strain PsJN(T) (=LMG 22146(T) = CCUG 49060(T)).
349 citations
TL;DR: The present article explains the nomenclatural consequences of Opinion 80, together with a clear presentation of the taxonomy that results when applying the currently widely accepted interpretation that the genus Salmonella currently includes only two species.
Abstract: The nomenclature of the genus Salmonella has reached an unsatisfactory state of affairs, with two systems of nomenclature in circulation. One system, proposed in the 1980s by Le Minor and Popoff, has received wide acceptance, although it does not conform to the rules of the Bacteriological Code. The other system, which conforms to the rules of the Bacteriological Code, is being used by an ever-decreasing minority. As a result of a number of recent Requests for an Opinion, the Judicial Commission of the International Committee on the Systematics of Prokaryotes has issued an Opinion (Opinion 80) with the intention that it should solve these discrepancies. However, like all Opinions, it is limited to matters of nomenclature and does not help to interpret the taxonomic consequences. The Judicial Commission has therefore asked experts in the field of nomenclature and taxonomy to write a commentary on the nomenclatural and taxonomic consequences of Opinion 80. The present article explains the nomenclatural consequences of Opinion 80, together with a clear presentation of the taxonomy that results when applying the currently widely accepted interpretation that the genus Salmonella currently includes only two species.
338 citations
TL;DR: A collection of 75 strains of Pectobacterium chrysanthemi and the type strains of Brenneria paradisiaca (CFBP 4178T) were studied by DNA-DNA hybridization, numerical taxonomy of 121 phenotypic characteristics, serology and 16S rRNA gene-based phylogenetic analyses as discussed by the authors.
Abstract: A collection of 75 strains of Pectobacterium chrysanthemi (including all biovars and pathovars) and the type strains of Brenneria paradisiaca (CFBP 4178T) and Pectobacterium cypripedii (CFBP 3613T) were studied by DNA–DNA hybridization, numerical taxonomy of 121 phenotypic characteristics, serology and 16S rRNA gene-based phylogenetic analyses. From analysis of 16S rRNA gene sequences, it was deduced that P. chrysanthemi strains and B. paradisiaca CFBP 4178T formed a clade distinct from the genera Pectobacterium and Brenneria; therefore, it is proposed to transfer all the strains to a novel genus, Dickeya gen. nov. By DNA–DNA hybridization, the strains of P. chrysanthemi were distributed among six genomic species: genomospecies 1 harbouring 16 strains of biovar 3 and four strains of biovar 8, genomospecies 2 harbouring 16 strains of biovar 3, genomospecies 3 harbouring two strains of biovar 6 and five strains of biovar 5, genomospecies 4 harbouring five strains of biovar 2, genomospecies 5 harbouring six strains of biovar 1, four strains of biovar 7 and five strains of biovar 9 and genomospecies 6 harbouring five strains of biovar 4 and B. paradisiaca CFBP 4178T. Two strains of biovar 3 remained unclustered. Biochemical criteria, deduced from a numerical taxonomic study of phenotypic characteristics, and serological reactions allowed discrimination of the strains belonging to the six genomic species. Thus, it is proposed that the strains clustered in these six genomic species be assigned to the species Dickeya zeae sp. nov. (type strain CFBP 2052T=NCPPB 2538T), Dickeya dadantii sp. nov. (type strain CFBP 1269T=NCPPB 898T), Dickeya chrysanthemi comb. nov. (subdivided into two biovars, bv. chrysanthemi and bv. parthenii), Dickeya dieffenbachiae sp. nov. (type strain CFBP 2051T=NCPPB 2976T), Dickeya dianthicola sp. nov. (type strain CFBP 1200T=NCPPB 453T) and Dickeya paradisiaca comb. nov., respectively.
338 citations
TL;DR: The present study confirmed that Anabaena and Aphanizomenon strains were not monophyletic, as previously demonstrated and showed that the current classification of these anabaenoid genera needs to be revised.
Abstract: The heterocytous cyanobacteria form a monophyletic group according to 16S rRNA gene sequence data. Within this group, phylogenetic and morphological studies have shown that genera such as Anabaena and Aphanizomenon are intermixed. Moreover, the phylogeny of the genus Trichormus, which was recently separated from Anabaena, has not been investigated. The aim was to study the taxonomy of the genera Anabaena, Aphanizomenon, Nostoc and Trichormus belonging to the family Nostocaceae (subsection IV.I) by morphological and phylogenetic analyses of 16S rRNA gene, rpoB and rbcLX sequences. New strains were isolated to avoid identification problems caused by morphological changes of strains during cultivation. Morphological and phylogenetic data showed that benthic and planktic Anabaena strains were intermixed. In addition, the present study confirmed that Anabaena and Aphanizomenon strains were not monophyletic, as previously demonstrated. The evolutionary distances between the strains indicated that the planktic Anabaena and Aphanizomenon strains as well as five benthic Anabaena strains in cluster 1 could be assigned to a single genus. On the basis of the 16S rRNA, rpoB and rbcLX gene sequences, the Anabaena/Aphanizomenon strains (cluster 1) were divided into nine supported subclusters which could also be separated morphologically, and which therefore might represent different species. Trichormus strains were morphologically and phylogenetically heterogeneous and did not form a monophyletic cluster. These Trichormus strains, which were representatives of three distinct species, might actually belong to three genera according to the evolutionary distances. Nostoc strains were also heterogeneous and seemed to form a monophyletic cluster, which may contain more than one genus. It was found that certain morphological features were stable and could be used to separate different phylogenetic clusters. For example, the width and the length of akinetes were useful features for classification of the Anabaena/Aphanizomenon strains in cluster 1. This morphological and phylogenetic study with fresh isolates showed that the current classification of these anabaenoid genera needs to be revised.
337 citations
TL;DR: Although the strains described were isolated from lesions and show several characteristics typical of pathogenic staphylococci, such as coagulase, DNase and beta-haemolysin production, the pathogenic significance of the novel species remains unclear.
Abstract: Four staphylococcal isolates from clinical and necropsy specimens from a cat, a dog, a horse and a parrot (Psittacus erithacus timneh) were found to constitute a distinct taxon. 16S rRNA gene sequence analysis revealed that its closest phylogenetic relatives are Staphylococcus intermedius and Staphylococcus delphini. Growth characteristics, biochemical features and DNA–DNA hybridizations demonstrated that the strains differ from these and other known species and that they represent a single, novel Staphylococcus species for which the name Staphylococcus pseudintermedius sp. nov. is proposed. The novel species is commonly confused with S. intermedius in routine diagnostic veterinary bacteriology. Although the strains described were isolated from lesions and show several characteristics typical of pathogenic staphylococci, such as coagulase, DNase and β-haemolysin production, the pathogenic significance of the novel species remains unclear. The type strain, LMG 22219T (=ON 86T=CCUG 49543T), was isolated from lung tissue of a cat.
337 citations
332 citations
TL;DR: A novel solvent-producing, anaerobic clostridium, strain P7(T), was isolated from sediment from an agricultural settling lagoon after enrichment with CO as the substrate and analysis of the 16S rRNA gene sequence showed that it was closely related to Clostridial scatologenes ATCC 25775(T) (99.7% sequence similarity).
Abstract: A novel solvent-producing, anaerobic clostridium, strain P7T, was isolated from sediment from an agricultural settling lagoon after enrichment with CO as the substrate. The metabolism of this Gram-positive, motile, spore-forming rod was primarily acetogenic. Acetate, ethanol, butyrate and butanol were the end-products of metabolism. Strain P7T grew on CO, H2/CO2, glucose, galactose, fructose, xylose, mannose, cellobiose, trehalose, cellulose, starch, pectin, citrate, glycerol, ethanol, propanol, 2-propanol, butanol, glutamate, aspartate, alanine, histidine, asparagine, serine, betaine, choline and syringate as sole substrates. Growth was not supported by methanol, formate, d-arabinose, fucose, lactose, melibiose, amygdalin, gluconate, lactate, malate, arginine, glutamine or vanillate. Nitrate reduction, production of indole, gelatin hydrolysis and aesculin hydrolysis were not observed. Analysis of the 16S rRNA gene sequence of the isolate showed that it was closely related to Clostridium scatologenes ATCC 25775T (99·7 % sequence similarity) and clostridial strain SL1T (99·8 % sequence similarity). Strain SL1 had been classified as a strain of C. scatologenes. However, DNA–DNA reassociation analysis showed that both strain P7T and strain SL1 represented novel clostridial species. It is proposed that strain P7T (=ATCC BAA-624T=DSM 15243T) be classified as the type strain of Clostridium carboxidivorans sp. nov. and that strain SL1T (=ATCC BAA-623T=DSM 12750T) be reclassified as the type strain of Clostridium drakei sp. nov.
332 citations
TL;DR: A new genus and species, Proteiniphilum acetatigenes gen. nov., is proposed, with strain TB107T (=JCM 12891T=AS 1.5024T) as the type strain, with <91 % 16S rRNA gene sequence similarity to the closest species with validly published names.
Abstract: Two proteolytic, strictly anaerobic bacterial strains (TB107T and TB6-6) were isolated from the granule sludge of an upflow anaerobic sludge blanket reactor treating brewery wastewater. The strains were Gram-negative, non-spore-forming and motile. Cells were rod-shaped (0·6–0·9×1·9–2·2 μm). Growth of the strains was observed at 20–45 °C and pH 6·0–9·7. The strains were proteolytic. Yeast extract, peptone, pyruvate, glycine and l-arginine could be used as carbon and energy sources. Weak growth was also observed with tryptone, l-serine, l-threonine and l-alanine as carbon and energy sources. Both strains did not use any of the tested carbohydrates, alcohols and fatty acids except pyruvate. Acetic acid and NH3 were produced from yeast extract, peptone and l-arginine, and propionic acid was also produced from yeast extract. Pyruvate was converted to acetic acid and CO2. Gelatin was not hydrolysed. Indole and H2S were not produced. The two strains did not grow in medium containing 20 % bile. Addition of strain TB107T to a syntrophic propionate-degrading co-culture accelerated the propionate-degradation rate. The predominant cellular fatty acid was the branched-chain fatty acid anteiso-C15 : 0 (46·21 %). The genomic DNA G+C contents of strains TB107T and TB6-6 were 46·6 and 48·9 mol%, respectively. Phylogenetic analysis based on 16S rRNA gene sequences revealed that the two strains represent a new phyletic sublineage within the Cytophaga–Flavobacterium–Bacteroides (CFB) group, with <91 % 16S rRNA gene sequence similarity to the closest species with validly published names. On the basis of polyphasic evidence from this study, a new genus and species, Proteiniphilum acetatigenes gen. nov., sp. nov., is proposed, with strain TB107T (=JCM 12891T=AS 1.5024T) as the type strain.
309 citations
TL;DR: A taxonomic study was carried out to clarify the taxonomy of representatives of a group of marine actinomycetes previously designated MAR 1 and considered to belong to the family Micromonosporaceae, which contains two species recognized using a range of genotypic and phenotypic criteria.
Abstract: A taxonomic study was carried out to clarify the taxonomy of representatives of a group of marine actinomycetes previously designated MAR 1 and considered to belong to the family Micromonosporaceae. The organisms had phenotypic properties consistent with their assignment to this taxon. The strains formed a distinct taxon in the 16S rRNA Micromonosporaceae gene tree and shared a range of phenotypic properties that distinguished them from members of all of the genera with validly published names classified in this family. The name proposed for this novel taxon is Salinispora gen. nov. The genus contains two species recognized using a range of genotypic and phenotypic criteria, including comparative 16S–23S rRNA gene spacer region and DNA–DNA relatedness data. The names proposed for these taxa are Salinispora arenicola sp. nov., the type species, and Salinispora tropica sp. nov.; the type strains of these novel species have been deposited in service culture collections as strain CNH-643T (=ATCC BAA-917T=DSM 44819T) and strain CNB-440T (=ATCC BAA-916T=DSM 44818T), respectively.
298 citations
TL;DR: Results of physiological and biochemical tests, DNA-DNA hybridization, comparisons of 16S-23S internal transcribed spacer sequences and comparisons of the partial deduced amino acid sequence of alkane hydroxylase showed that both strains were affiliated to the genus Alcanivorax but were differentiated from recognized Alcanvorax species.
Abstract: Two bacterial strains, B-5T and NO1A, were isolated from the surface water of the Bohai Sea and deep-sea sediment of the east Pacific Ocean, respectively. Both strains were halophilic, aerobic, Gram-negative, non-spore-forming, catalase- and oxidase-positive motile rods. They grew on a restricted spectrum of organic compounds, including some organic acids and alkanes. On the basis of 16S rRNA gene sequence similarity, strains B-5T and NO1A were shown to belong to the γ-Proteobacteria. Highest similarity values were found with Alcanivorax venustensis (95·2 %), Alcanivorax jadensis (94·6 %) and Alcanivorax borkumensis (94·1 %). Principal fatty acids of both strains were C16 : 0, C16 : 1 ω7c and C18 : 1 ω7c. The chemotaxonomically characteristic fatty acid C19 : 0 cyclo ω8c was also detected. On the basis of the above, together with results of physiological and biochemical tests, DNA–DNA hybridization, comparisons of 16S–23S internal transcribed spacer sequences and comparisons of the partial deduced amino acid sequence of alkane hydroxylase, both strains were affiliated to the genus Alcanivorax but were differentiated from recognized Alcanivorax species. Therefore, a novel species, Alcanivorax dieselolei sp. nov., represented by strains B-5T and NO1A is proposed, with the type strain B-5T (=DSM 16502T=CGMCC 1.3690T).
TL;DR: This novel organism possesses phenotypic, chemotaxonomic and phylogenetic traits that do not allow its classification as a member of any previously described genus; therefore, it is proposed that this isolate should be described as a members of a novel species of a new genus, Petrimonas gen. nov.
Abstract: A mesophilic, anaerobic, fermentative bacterium, strain BN3(T), was isolated from a producing well of a biodegraded oil reservoir in Canada. Cells were Gram-negative, non-motile rods that did not form spores. The temperature range for growth was 15-40 degrees C, with optimum growth at 37-40 degrees C. The strain grew with up 4 % NaCl, with optimum growth in the absence of NaCl. Tryptone was required for growth. Yeast extract and elemental sulfur stimulated growth. Growth was also enhanced during fermentation of glucose, arabinose, galactose, maltose, mannose, rhamnose, lactose, ribose, fructose, sucrose, cellobiose, lactate, mannitol and glycerol. Acetate, hydrogen and CO(2) were produced during glucose fermentation. Elemental sulfur and nitrate were used as electron acceptors and were reduced to sulfide and ammonium, respectively. The G + C content of the genomic DNA was 40.8 mol%. Phylogenetic analyses of the 16S rRNA gene sequence indicated that the strain was a member of the phylum 'Bacteroidetes', distantly related to the genera Bacteroides and Tannerella (similarity values of less than 90 %). The chemotaxonomic data (fatty acids, polar lipids and quinones composition) also indicated that strain BN3(T) could be clearly distinguished from its closest cultivated relatives. This novel organism possesses phenotypic, chemotaxonomic and phylogenetic traits that do not allow its classification as a member of any previously described genus; therefore, it is proposed that this isolate should be described as a member of a novel species of a new genus, Petrimonas gen. nov., of which Petrimonas sulfuriphila sp. nov. is the type species. The type strain is BN3(T) (= DSM 16547(T) = JCM 12565(T)).
TL;DR: Results confirm that the SPS-HLB liberibacter is a novel species for which the name 'Candidatus Liberibacter americanus' is proposed, and like the African and the Asian liberibacters, the 'American' liberibacteria is restricted to the sieve tubes of the citrus host.
Abstract: Full Text (PDF) Supplementary Table Alert me when this article is cited Alert me if a correction is posted Citation Map ABSTRACT TOP ABSTRACT MAIN TEXT REFERENCES Symptoms of huanglongbing (HLB) were reported in Sao Paulo State (SPS), Brazil, in March 2004. In Asia, HLB is caused by 'Candidatus Liberibacter asiaticus' and in Africa by 'Candidatus Liberibacter africanus'. Detection of the liberibacters is based on PCR amplification of their 16S rRNA gene with specific primers. Leaves with blotchy mottle symptoms characteristic of HLB were sampled in several farms of SPS and tested for the presence of liberibacters. 'Ca. L. asiaticus' was detected in a small number of samples but most samples gave negative PCR results. Therefore, a new HLB pathogen was suspected. Evidence for an SPS-HLB bacterium in symptomatic leaves was obtained by PCR amplification with universal primers for prokaryotic 16S rRNA gene sequences. The amplified 16S rRNA gene was cloned and sequenced. Sequence analysis and phylogeny studies showed that the 16S rRNA gene possessed the oligonucleotide signatures and the secondary loop structure characteristic of the -Proteobacteria, including the liberibacters. The 16S rRNA gene sequence phylogenetic tree showed that the SPS-HLB bacterium clustered within the -Proteobacteria, the liberibacters being its closest relatives. For these reasons, the SPS-HLB bacterium is considered a member of the genus 'Ca. Liberibacter'. However, while the 16S rRNA gene sequences of 'Ca. L. asiaticus' and 'Ca. L. africanus' had 98·4 % similarity, the 16S rRNA gene sequence of the SPS- HLB liberibacter had only 96·0 % similarity with the 16S rRNA gene sequences of 'Ca. L. asiaticus' or 'Ca. L. africanus'. This lower similarity was reflected in the phylogenetic tree, where the SPS-HLB liberibacter did not cluster within the 'Ca. L asiaticus'/'Ca. L. africanus group', but as a separate branch. Within the genus 'Candidatus Liberibacter' and for a given species, the 16S/23S intergenic region does not vary greatly. The intergenic regions of three strains of 'Ca. L. asiaticus', from India, the People's Republic of China and Japan, were found to have identical or almost identical sequences. In contrast, the intergenic regions of the SPS-HLB liberibacter, 'Ca. L. asiaticus' and 'Ca. L. africanus' had quite different sequences, with similarity between 66·0 and 79·5 %. These results confirm that the SPS-HLB liberibacter is a novel species for which the name 'Candidatus Liberibacter americanus' is proposed. Like the
TL;DR: It is a requirement of IJSEM and the ICSP that authors of new species, new subspecies and new combinations provide evidence that types are deposited in two recognized culture collections in two different countries.
Abstract: The purpose of this announcement is to effect the valid publication of the following new names and new combinations under the procedure described in the Bacteriological Code (1990 Revision). Authors and other individuals wishing to have new names and/or combinations included in future lists should send three copies of the pertinent reprint or photocopies thereof to the IJSEM Editorial Office for confirmation that all of the other requirements for valid publication have been met. It is also a requirement of IJSEM and the ICSP that authors of new species, new subspecies and new combinations provide evidence that types are deposited in two recognized culture collections in two different countries (i.e. documents certifying deposition and availability of type strains). It should be noted that the date of valid publication of these new names and combinations is the date of publication of this list, not the date of the original publication of the names and combinations. The authors of the new names and combinations are as given below, and these authors' names will be included in the author index of the present issue and in the volume author index. Inclusion of a name on these lists validates the publication of the name and thereby makes it available in bacteriological nomenclature. The inclusion of a name on this list is not to be construed as taxonomic acceptance of the taxon to which the name is applied. Indeed, some of these names may, in time, be shown to be synonyms, or the organisms may be transferred to another genus, thus necessitating the creation of a new combination.
TL;DR: The results demonstrate that, in this case, the concatenation of different genes allows significant increases in the power of discrimination and the robustness of the phylogenetic tree.
Abstract: Advances in DNA sequencing and the increasing number of sequences available in databases have greatly enhanced the bacterial identification process. Several species within the genus Mycobacterium cause serious human and animal diseases. In order to assess their relative positions in the evolutionary process, four gene fragments, from the 16S rRNA (564 bp), hsp65 (420 bp), rpoB (396 bp) and sod (408 bp) genes, were sequenced from 97 strains, including all available type strains of the genus Mycobacterium. The results demonstrate that, in this case, the concatenation of different genes allows significant increases in the power of discrimination and the robustness of the phylogenetic tree. The sequential and/or combined use of sequences of several genes makes it possible to refine the phylogenetic approach and provides a molecular basis for accurate species identification.
TL;DR: In addition to the currently described species, this phylogeny uncovered the novel Bradyrhizobium genospecies alpha and beta and the photosynthetic strains as independent evolutionary lineages.
Abstract: Highly diverse Bradyrhizobium strains nodulate genistoid legumes (brooms) in the Canary Islands, Morocco, Spain and the Americas. Phylogenetic analyses of ITS, atpD, glnII and recA sequences revealed that these isolates represent at least four distinct evolutionary lineages within the genus, namely Bradyrhizobium japonicum and three unnamed genospecies. DNA–DNA hybridization experiments confirmed that one of the latter represents a new taxonomic species for which the name Bradyrhizobium canariense is proposed. B. canariense populations experience homologous recombination at housekeeping loci, but are sexually isolated from sympatric B. japonicum bv. genistearum strains in soils of the Canary Islands. B. canariense strains are highly acid-tolerant, nodulate diverse legumes in the tribes Genisteae and Loteae, but not Glycine species, whereas acid-sensitive B. japonicum soybean isolates such as USDA 6T and USDA 110 do not nodulate genistoid legumes. Based on host-range experiments and phylogenetic analyses of symbiotic nifH and nodC sequences, the biovarieties genistearum and glycinearum for the genistoid legume and soybean isolates, respectively, were proposed. B. canariense bv. genistearum strains display an overlapped host range with B. japonicum bv. genistearum isolates, both sharing monophyletic nifH and nodC alleles, possibly due to the lateral transfer of a conjugative chromosomal symbiotic island across species. B. canariense is the sister species of B. japonicum, as inferred from a maximum-likelihood Bradyrhizobium species phylogeny estimated from congruent glnII+recA sequence partitions, which resolves eight species clades. In addition to the currently described species, this phylogeny uncovered the novel Bradyrhizobium genospecies alpha and beta and the photosynthetic strains as independent evolutionary lineages. The type strain for B. canariense is BTA-1T (=ATCC BAA-1002T=LMG 22265T=CFNE 1008T).
TL;DR: The taxonomic positions of six strains of Chryseobacterium meningosepticum and C. miricola were re-evaluated by using a polyphasic taxonomic approach and phylogenetic and phenotypic data showed that they should be transferred to a new genus, Elizabethkingia gen. nov.
Abstract: The taxonomic positions of six strains (including the type strain) of Chryseobacterium meningosepticum (King 1959) Vandamme et al. 1994 and the type strain of Chryseobacterium miricola Li et al. 2004 were re-evaluated by using a polyphasic taxonomic approach. Phylogenetic analysis, based on 16S rRNA gene sequencing, showed that the strains represent a separate lineage from the type strains of the Chryseobacterium-Bergeyella-Riemerella branch within the family Flavobacteriaceae (90.7-93.9 % similarities), which was supported by phenotypic differences. Combined phylogenetic and phenotypic data showed that C. meningosepticum and C. miricola should be transferred to a new genus, Elizabethkingia gen. nov., with the names Elizabethkingia meningoseptica comb. nov. (type strain, ATCC 13253(T) = NCTC 10016(T) = LMG 12279(T) = CCUG 214(T)) and Elizabethkingia miricola comb. nov. (type strain, DSM 14571(T) = JCM 11413(T) = GTC 862(T)) proposed.
TL;DR: The phylogenetic tree of 16S rRNA gene sequences established in this study may provide a sound basis for future taxonomic reconstruction of the class 'Alphaproteobacteria', including physiologically diverse species.
Abstract: Phylogenetic analysis of the class 'Alphaproteobacteria', including physiologically diverse species, was conducted by using small-subunit rRNA gene sequences. The 16S rRNA gene sequences of 261 species in the class 'Alphaproteobacteria' were obtained from GenBank/EMBL/DDBJ for constructing a phylogenetic tree by using maximum-likelihood analysis. In the resulting tree, members of the class 'Alphaproteobacteria' were subdivided into five major clusters, which were compared with the taxonomic outline of Bergey's Manual of Systematic Biology and the arb tree. Based on this phylogenetic tree, three novel families are proposed: Hyphomonadaceae fam. nov. to accommodate the bacterial genera Hyphomonas, Hirschia, Maricaulis and Oceanicaulis, Xanthobacteraceae fam. nov. to include the genera Xanthobacter, Azorhizobium, Ancylobacter, Labrys and Starkeya, and Erythrobacteraceae fam. nov. to accommodate the genera Erythrobacter, Porphyrobacter and Erythromicrobium. The phylogenetic tree of 16S rRNA gene sequences established in this study may provide a sound basis for future taxonomic reconstruction of the class 'Alphaproteobacteria'.
TL;DR: Four N(2)O-producing facultative aerobes, ED1(T), ED5 (T), MH21(T) and MH72, were isolated from the gut of the earthworms and are proposed as type strains of the novel species Dechloromonas denitrificans sp.
Abstract: Earthworms emit nitrous oxide (N2O) via the activity of bacteria in their gut. Four N2O-producing facultative aerobes, ED1T, ED5T, MH21T and MH72, were isolated from the gut of the earthworm Aporrectodea caliginosa. The isolates produced N2O under conditions that simulated the microenvironment of the earthworm gut. ED1T and ED5T were Gram-negative, motile rods that carried out complete denitrification (i.e. the reduction of nitrate to N2) and contained membranous c-type cytochromes. ED1T grew optimally at 30 °C and pH 7. ED1T oxidized organic acids and reduced (per)chlorate, sulfate, nitrate and nitrite. The closest phylogenetic relative of ED1T was Dechloromonas agitata. ED5T grew optimally at 25 °C and pH 7. ED5T grew mainly on sugars, and nitrate and nitrite were used as alternative electron acceptors. The closest phylogenetic relatives of ED5T were Flavobacterium johnsoniae and Flavobacterium flevense. MH21T and MH72 were motile, spore-forming, rod-shaped bacteria with a three-layered cell wall. Sugars supported the growth of MH21T and MH72. Cells of MH21T grew in chains, were linked by connecting filaments and contained membranous b-type cytochromes. MH21T grew optimally at 30–35 °C and pH 7·7, grew by fermentation and reduced low amounts of nitrite to N2O. The closest phylogenetic relatives of MH21T were Paenibacillus borealis and Paenibacillus chibensis. Based on morphological, physiological and phylogenetic characteristics, ED1T (=DSM 15892T=ATCC BAA-841T), ED5T (=DSM 15936T=ATCC BAA-842T) and MH21T (=DSM 15890T=ATCC BAA-844T) are proposed as type strains of the novel species Dechloromonas denitrificans sp. nov., Flavobacterium denitrificans sp. nov. and Paenibacillus anaericanus sp. nov., respectively. MH72 is considered a new strain of Paenibacillus terrae.
TL;DR: Two Gram-positive, endospore-forming bacterial strains, CR-502T and CR-14b, which produce surfactant molecules are described and it is proposed that these strains be classified as a novel species of the genus Bacillus, with the name Bacillus velezensis sp.
Abstract: Two Gram-positive, endospore-forming bacterial strains, CR-502T and CR-14b, which produce surfactant molecules are described. Phenotypic tests and phylogenetic analyses showed these strains to be members of the genus Bacillus and related to the species Bacillus atrophaeus, Bacillus mojavensis, Bacillus subtilis, Bacillus vallismortis and Bacillus amyloliquefaciens, although they differ from these species in a number of phenotypic characteristics. DNA-DNA hybridization confirmed that they show less than 20 % hybridization with the above-mentioned species and therefore represent a novel species of Bacillus. The DNA G+C content is 46.4 mol% in strain CR-502T and 46.1 mol% in strain CR-14b. The main fatty acids in strain CR-502T are 15 : 0 anteiso (32.70 %), 15 : 0 iso (29.86 %) and 16 : 0 (13.41 %). The main quinone in strain CR-502T is MK-7 (96.6 %). In the light of the polyphasic evidence gathered in this study, it is proposed that these strains be classified as a novel species of the genus Bacillus, with the name Bacillus velezensis sp. nov. The type strain (CR-502T=CECT 5686T=LMG 22478T) was isolated from a brackish water sample taken from the river Velez at Torredelmar in Malaga, southern Spain.
TL;DR: Overall support for much of the phylogenies is decreased over previous analyses that concatenated fewer genes for fewer taxa, Nevertheless, four of the six chromalveolate lineages consistently form a monophyletic assemblage, whereas the remaining two form a weakly supported group.
Abstract: A global phylogeny of major eukaryotic lineages is a significant and ongoing challenge to molecular phylogenetics. Currently, there are five hypothesized major lineages or 'supergroups' of eukaryotes. One of these, the chromalveolates, represents a large fraction of protist and algal diversity. The chromalveolate hypothesis was originally based on similarities between the photosynthetic organelles (plastids) found in many of its members and has been supported by analyses of plastid-related genes. However, since plastids can move between eukaryotic lineages, it is important to provide additional support from data generated from the nuclear-cytosolic host lineage. Genes coding for six different cytosolic proteins from a variety of chromalveolates (yielding 68 new gene sequences) have been characterized so that multiple gene analyses, including all six major lineages of chromalveolates, could be compared and concatenated with data representing all five hypothesized supergroups. Overall support for much of the phylogenies is decreased over previous analyses that concatenated fewer genes for fewer taxa. Nevertheless, four of the six chromalveolate lineages (apicomplexans, ciliates, dinoflagellates and heterokonts) consistently form a monophyletic assemblage, whereas the remaining two (cryptomonads and haptophytes) form a weakly supported group. Whereas these results are consistent with the monophyly of chromalveolates inferred from plastid data, testing this hypothesis is going to require a substantial increase in data from a wide variety of organisms.
TL;DR: A novel group of aerobic anoxygenic phototrophic bacteria was isolated from marine dinoflagellates, and two strains were characterized in detail, and it is proposed to classify the strains in a new genus and species within the Roseobacter clade, Dinoroseobacter shibae gen. nov.
Abstract: A novel group of aerobic anoxygenic phototrophic bacteria was isolated from marine dinoflagellates, and two strains were characterized in detail. Cells were Gram-negative cocci or ovoid rods and were motile by means of a single, polarly inserted flagellum. They were obligate aerobes requiring 1–7 % salinity. The optimal pH range for growth was 6·5–9·0 and the temperature optimum was 33 °C. The bacteria contained bacteriochlorophyll a and spheroidenone as the only carotenoid. The in vivo absorption spectrum displayed two maxima in the infrared region at 804 and 868 nm. The distinct 804 nm band indicates the presence of light-harvesting system 2. Various organic carbon sources were assimilated, including many carboxylic acids, glucose and glycerol, but not butyrate, ethanol or methanol. Dissimilatory nitrate reduction was found for both strains. The physiological characteristics of the new strains resembled those of Roseobacter denitrificans, but there were differences in the lipid composition. Based on 16S rRNA gene sequence analysis the new strains are relatively distant from other recognized species, with the closest relatives Jannaschia helgolandensis, Ruegeria atlantica and Rhodobacter veldkampii showing 94·1–93·4 % similarity. Similarity to Roseobacter denitrificans was only 92·2 %, in line with numerous other species of the Roseobacter group. Therefore, it is proposed to classify the strains in a new genus and species within the Roseobacter clade, Dinoroseobacter shibae gen. nov., sp. nov. The type strain is DFL 12T (=DSM 16493T=NCIMB 14021T).
TL;DR: Differences in phenotypic and phylogenetic characteristics indicated that the four isolates represent two novel species within the genus Geobacter, and all four strains are delta-proteobacteria and members of the Geobacteria cluster of theGeobacteraceae.
Abstract: Fe(III)-reducing isolates were recovered from two aquifers in which Fe(III) reduction is known to be important. Strain BemT was enriched from subsurface sediments collected in Bemidji, MN, USA, near a site where Fe(III) reduction is important in aromatic hydrocarbon degradation. Strains P11, P35T and P39 were isolated from the groundwater of an aquifer in Plymouth, MA, USA, in which Fe(III) reduction is important because of long-term inputs of acetate as a highway de-icing agent to the subsurface. All four isolates were Gram-negative, slightly curved rods that grew best in freshwater media. Strains P11, P35T and P39 exhibited motility via means of monotrichous flagella. Analysis of the 16S rRNA and nifD genes indicated that all four strains are δ-proteobacteria and members of the Geobacter cluster of the Geobacteraceae. Differences in phenotypic and phylogenetic characteristics indicated that the four isolates represent two novel species within the genus Geobacter. All of the isolates coupled the oxidation of acetate to the reduction of Fe(III) [iron(III) citrate, amorphous iron(III) oxide, iron(III) pyrophosphate and iron(III) nitrilotriacetate]. All four strains utilized ethanol, lactate, malate, pyruvate and succinate as electron donors and malate and fumarate as electron acceptors. Strain BemT grew fastest at 30 °C, whereas strains P11, P35T and P39 grew equally well at 17, 22 and 30 °C. In addition, strains P11, P35T and P39 were capable of growth at 4 °C. The names Geobacter bemidjiensis sp. nov. (type strain BemT=ATCC BAA-1014T=DSM 16622T=JCM 12645T) and Geobacter psychrophilus sp. nov. (strains P11, P35T and P39; type strain P35T=ATCC BAA-1013T=DSM 16674T=JCM 12644T) are proposed.
TL;DR: The results obtained suggest that 604 bp hsp65 sequences are useful for the phylogenetic analysis and species identification of mycobacteria.
Abstract: The nucleotide sequences (604 bp) of partial heat-shock protein genes (hsp65) from 161 Mycobacterium strains containing 56 reference Mycobacterium species and 105 clinical isolates were determined and compared. hsp65 sequence analysis showed a higher degree of divergence between Mycobacterium species than did 16S rRNA gene analysis. Generally, the topology of the phylogenetic tree based on the hsp65 DNA sequences was similar to that of the 16S rRNA gene, thus revealing natural relationships among Mycobacterium species. When a direct sequencing protocol targeting 422 bp sequences was applied to 70 non-tuberculous mycobacterium (NTM) clinical isolates, all NTMs were clearly identified. In addition, an XhoI PCR restriction fragment length polymorphism analysis method for the differentiation of Mycobacterium tuberculosis complex from NTM strains was developed during this study. The results obtained suggest that 604 bp hsp65 sequences are useful for the phylogenetic analysis and species identification of mycobacteria.
TL;DR: It is proposed that this actinomycete, strain FXJ46(T), was isolated from cypress forest soil in northern China and shown to have chemotaxonomic and morphological properties consistent with streptomycetes, be classified as a novel species of the genus Streptomyces.
Abstract: An actinomycete, strain FXJ46T, was isolated from cypress forest soil in northern China and shown to have chemotaxonomic and morphological properties consistent with streptomycetes. It developed greyish aerial mycelium and pinkish-brown substrate mycelium on oatmeal agar. Phylogenetic analyses based on an almost complete 16S rRNA gene sequence of the strain and on the 120 nucleotide variable γ-region of this molecule showed that it formed a distinct (but closely associated) line with Streptomyces griseoaurantiacus DSM 40430T in Streptomyces trees. However, the DNA–DNA relatedness between the two strains was only 48·8 %. A number of phenotypic properties also readily distinguished the isolate from S. griseoaurantiacus and related Streptomyces species with validly published names. It is proposed, therefore, that this organism be classified as a novel species of the genus Streptomyces, for which the name Streptomyces jietaisiensis sp. nov. is proposed. The type strain is FXJ46T (=AS 4.1859T=JCM 12279T).
TL;DR: Examination of 110 bacterial isolates cultivated from the gastrointestinal tract of 23 mice revealed the presence of a subgroup of 30 isolates that did not correspond genetically with genera commonly associated with this site, i.e. members of the epsilon-Proteobacteria such as Helicobacter and Campylobacter species.
Abstract: The mammalian gastrointestinal tract is covered by a layer of mucus that can harbour a range of bacterial species specifically adapted to colonize this ecological niche. Examination of 110 bacterial isolates cultivated from the gastrointestinal tract of 23 mice revealed the presence of a subgroup of 30 isolates that did not correspond genetically with genera commonly associated with this site, i.e. members of the e-Proteobacteria such as Helicobacter and Campylobacter species. Instead this group of isolates was found to lie within the phylum Deferribacteres, a completely distinct lineage in the domain Bacteria. There was a high level of consensus in results obtained from the phenotypic and genotypic characterization of a number of the isolates, which showed they were distinct from other members of the Deferribacteres. As such, they are proposed to constitute a new genus and species, Mucispirillum schaedleri gen. nov., sp. nov. These organisms are anaerobic, Gram-negative, spiral-shaped rods with bipolar flagella. The type strain is HRI I17T (=ATCC BAA-1009T=ACM 5223T).
TL;DR: A novel species is proposed, by virtue of its unique properties, under the designation 'Candidatus Erwinia dacicola', which differs from common intestinal bacterial species of fruit flies and from instances of culturable bacteria previously described in B. oleae raised without sterility precautions.
Abstract: The taxonomic identity of the hereditary prokaryotic symbiont of the olive fly Bactrocera oleae (Diptera: Tephritidae) was investigated. In order to avoid superficial microbial contaminants and loosely associated saprophytic biota, flies were surface-sterilized at the larval stage and reared under aseptic conditions until adult emergence. B. oleae flies originating from different geographical locations and collected at different times of the year were tested. Bacterial isolation was undertaken from the cephalic oesophageal bulb, which is known to be a specific site of accumulation for the hosted microsymbionts in the adult insect. Despite evidence of multiplication cycles taking place within the insect, attempts at cultivation of the isolated bacteria ex situ were not productive at any stage, leading to the choice of unculturable status definition. PCR amplification and nucleotide sequencing of the entire 16S rRNA gene consistently yielded a single sequence that displayed marked similarity with enterobacterial lineages, with closest matches (97 %) to Erwinia persicina and Erwinia rhapontici. The novel taxon differs from common intestinal bacterial species of fruit flies and from instances of culturable bacteria previously described in B. oleae raised without sterility precautions, which we also observed as minority occupants or occasional contaminants. The symbiont's identity is also distinct from Pseudomonas savastanoi. In all observations, the numerically dominant inhabitant of the olive fly oesophageal organ was the same unculturable organism, whose presence at later stages was also regularly observed in the midgut. A novel species is proposed, by virtue of its unique properties, under the designation ‘Candidatus Erwinia dacicola’.
TL;DR: Two gamma- and UV-radiation-tolerant, Gram-negative, rod-shaped bacterial strains, VCD115T and VCD117, were isolated from a mixture of sand samples collected in the Sahara Desert after exposure of the sand to 15 kGy gamma radiation, showing affiliation to the genus Deinococcus.
Abstract: Two gamma- and UV-radiation-tolerant, Gram-negative, rod-shaped bacterial strains, VCD115T and VCD117, were isolated from a mixture of sand samples collected in the Sahara Desert in Morocco and Tunisia, after exposure of the sand to 15 kGy gamma radiation. Phylogenetic analysis based on 16S rRNA gene sequences and DNA–DNA hybridizations showed that VCD115T and VCD117 are members of a novel species belonging to the genus Deinococcus, with Deinococcus grandis as its closest relative. The DNA G+C contents of VCD115T and VCD117 are 59·8 and 60·6 mol%, respectively. The major fatty acids (straight-chain 15 : 1, 16 : 1, 17 : 1 and 16 : 0), polar lipids (dominated by phosphoglycolipids and glycolipids) and quinone type (MK-8) support the affiliation to the genus Deinococcus. The strains did not grow on rich medium such as trypticase soy broth (TSB), but did grow as whitish colonies on tenfold-diluted TSB. The genotypic and phenotypic properties allowed differentiation of VCD115T and VCD117 from recognized Deinococcus species. Strains VCD115T and VCD117 are therefore identified as representing a novel species, for which the name Deinococcus deserti sp. nov. is proposed, with the type strain VCD115T (=DSM 17065T=LMG 22923T).
TL;DR: The results of DNA-DNA hybridization, phenotypic tests and fatty acid analyses confirmed that this strain represents a novel species of the genus Phyllobacterium, for which the name PhyllOBacterium trifolii sp.
Abstract: Bacterial strain PETP02(T) was isolated from nodules of Trifolium pratense growing in a Spanish soil. Phylogenetic analysis of the 16S rRNA gene sequence showed that this strain represents a member of the genus Phyllobacterium. However, divergence found with the 16S rRNA gene sequence of the single recognized species of this genus, Phyllobacterium myrsinacearum, indicated that strain PETP02(T) belongs to a different species. The results of DNA-DNA hybridization, phenotypic tests and fatty acid analyses confirmed that this strain represents a novel species of the genus Phyllobacterium, for which the name Phyllobacterium trifolii sp. nov. is proposed. The type strain is PETP02(T) (=LMG 22712(T)=CECT 7015(T)). This strain was strictly aerobic and used several carbohydrates as carbon source. It was not able to reduce nitrate. Aesculin hydrolysis was negative. It did not produce urease, arginine dihydrolase, gelatinase or beta-galactosidase. The DNA G+C content was 56.4 mol%. The nodD gene of this strain showed a sequence closely related to those of strains able to nodulate Lupinus. Infectivity tests showed that this strain is able to produce nodules in both Trifolium repens and Lupinus albus.
TL;DR: Data demonstrate that the 20 isolates represent a single novel Arcobacter species, for which the nameArcobacter cibarius sp.
Abstract: Twenty Gram-negative, rod-shaped, slightly curved, non-spore-forming bacteria that gave a negative result in Arcobacter species-specific PCR tests but that yielded an amplicon in an Arcobacter genus-specific PCR test were isolated from 13 unrelated broiler carcasses. Numerical analysis of the profiles obtained by SDS-PAGE of whole-cell proteins clustered all isolates in a single group distinct from the other Arcobacter species. DNA–DNA hybridization among four representative strains exhibited DNA binding values above 91 %. DNA–DNA hybridization with reference strains of the current four Arcobacter species revealed binding levels below 47 %. The G+C contents ranged between 26·8 and 27·3 mol%. Pairwise comparison of 16S rRNA gene sequences revealed the mean values for similarity to the type strain of Arcobacter cryaerophilus (97·5 %), Arcobacter butzleri (96·5 %), Arcobacter skirrowii (96·0 %) and Arcobacter nitrofigilis (95·0 %). The levels of similarity to Campylobacter and Helicobacter species were below 88 and 87 %, respectively. The isolates could be distinguished from other Arcobacter species by the following biochemical tests: catalase, oxidase and urease activities; reduction of nitrate; growth at 25 and 37 °C under aerobic conditions; growth on 2–4 % (w/v) NaCl media; and susceptibility to cephalothin. These data demonstrate that the 20 isolates represent a single novel Arcobacter species, for which the name Arcobacter cibarius sp. nov. is proposed, with LMG 21996T (=CCUG 48482T) as the type strain.