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Showing papers on "Salinispora arenicola published in 2014"


Journal ArticleDOI
12 Mar 2014-PLOS ONE
TL;DR: In this paper, the authors investigated the species-level chemical diversity of the two marine actinobacterial species Salinispora arenicola and S. pacifica, isolated from sponges distributed across the Great Barrier Reef (GBR) using LC-MS-based metabolomics.
Abstract: Patterns of inter-species secondary metabolite production by bacteria can provide valuable information relating to species ecology and evolution. The complex nature of this chemical diversity has previously been probed via directed analyses of a small number of compounds, identified through targeted assays rather than more comprehensive biochemical profiling approaches such as metabolomics. Insights into ecological and evolutionary relationships within bacterial genera can be derived through comparative analysis of broader secondary metabolite patterns, and this can also eventually assist biodiscovery search strategies for new natural products. Here, we investigated the species-level chemical diversity of the two marine actinobacterial species Salinispora arenicola and Salinispora pacifica, isolated from sponges distributed across the Great Barrier Reef (GBR), via their secondary metabolite profiles using LC-MS-based metabolomics. The chemical profiles of these two species were obtained by UHPLC-QToF-MS based metabolic profiling. The resultant data were interrogated using multivariate data analysis methods to compare their (bio)chemical profiles. We found a high level of inter-species diversity in strains from these two bacterial species. We also found rifamycins and saliniketals were produced exclusively by S. arenicola species, as the main secondary metabolites differentiating the two species. Furthermore, the discovery of 57 candidate compounds greatly increases the small number of secondary metabolites previously known to be produced by these species. In addition, we report the production of rifamycin O and W, a key group of ansamycin compounds, in S. arenicola for the first time. Species of the marine actinobacteria harbour a much wider spectrum of secondary metabolites than suspected, and this knowledge may prove a rich field for biodiscovery as well as a database for understanding relationships between speciation, evolution and chemical ecology.

32 citations


Journal ArticleDOI
TL;DR: Rec recombinant expression studies are reported, indicating that this three-gene operon leads to the production of isopimara-8,15-dien-19-ol, suggesting that the terp1 operon is only expressed under certain physiologically relevant conditions such as in the presence of other marine organisms.
Abstract: While more commonly associated with plants than microbes, diterpenoid natural products have been reported to have profound effects in marine microbe–microbe interactions. Intriguingly, the genome of the marine bacterium Salinispora arenicola CNS-205 contains a putative diterpenoid biosynthetic operon, terp1. Here recombinant expression studies are reported, indicating that this three-gene operon leads to the production of isopimara-8,15-dien-19-ol (4). Although 4 is not observed in pure cultures of S. arenicola, it is plausible that the terp1 operon is only expressed under certain physiologically relevant conditions such as in the presence of other marine organisms.

29 citations


Journal ArticleDOI
TL;DR: To investigate the effects of growth conditions related to marine habitat on antibiotic production in sponge‐derived Salinispora actinobacteria, a phytochemical process called ‘spatially aggregating’ is studied.
Abstract: Aims: To investigate the effects of growth conditions related to marine habitat on antibiotic production in sponge-derived Salinispora actinobacteria. Methods and Results: Media with varying salt concentration were used to investigate the effects of salinity in relation to Salinispora growth and rifamycin production. The chemotypic profiles of the model strain Salinispora arenicola M413 was then assessed using metabolomic fingerprints from high-pressure liquid chromatography with diode array detection (HPLC-DAD) and multivariate data analysis, before extending this approach to two other strains of S. arenicola. Fingerprint data were generated from extracts of S. arenicola broth cultures grown in media of varying salt (NaCl) concentrations. These fingerprints were then compared using multivariate analysis methods such as principal components analysis (PCA) and orthogonal projection to latent structures discriminant analysis (OPLS-DA). From the analysis, a low-sodium growth condition (1% NaCl) was found to delay the onset of growth of the model S. arenicola M413 strain when compared to growth in media with either 3% artificial sea salt or 3% NaCl. However, low-sodium growth conditions also increased cell mass yield and contributed to at least a significant twofold increase in rifamycin yield when compared to growth in 3% artificial sea salt and 3% NaCl. Conclusions: The integration of HPLC-DAD and multivariate analysis proved to be an effective method of assessing chemotypic variations in Salinispora grown in different salt conditions, with clear differences between strain-related chemotypes apparent due to varying salt concentrations. Significance and Impact of the Study: The observed variation in S. arenicola chemotypic profiles further suggests diversity in secondary metabolites in this actinomycete in response to changes in the salinity of its environment.

18 citations


Journal ArticleDOI
TL;DR: Evidence of a much wider geographical distribution and secondary metabolism diversity in this genus than previously projected is provided, and salinosporamide biosynthetic genes, which are highly homologous to those of Bahamas-endemic S. tropica, were detected in several Tosa Bay isolates, making this report the first detection of Salinispora genes in S. arenicola.
Abstract: The obligate marine actinobacterium Salinispora arenicola was successfully cultured from temperate sediments of the Pacific Ocean (Tosa Bay, offshore Kochi Prefecture, Japan) with the highest latitude of 33°N ever reported for this genus. Based on 16S rRNA gene sequence analysis, the Tosa Bay strains are of the same phylotype as the type strain S. arenicola NBRC105043. However, sequence analysis of their 16S-23S rRNA intergenic spacer (ITS) revealed novel sequence variations. In total, five new ITS sequences were discovered and further phylogenetic analyses using gyrase B and rifamycin ketosynthase (KS) domain sequences supported the phylogenetic diversity of the novel Salinispora isolates. Screening of secondary metabolite genes in these strains revealed the presence of KS1 domain sequences previously reported in S. arenicola strains isolated from the Sea of Cortez, the Bahamas and the Red Sea. Moreover, salinosporamide biosynthetic genes, which are highly homologous to those of Bahamas-endemic S. tropica, were detected in several Tosa Bay isolates, making this report the first detection of salinosporamide genes in S. arenicola. The results of this study provide evidence of a much wider geographical distribution and secondary metabolism diversity in this genus than previously projected.

13 citations


Journal ArticleDOI
TL;DR: The occurrence of cycloaspeptide A, a fungus-derived cyclic peptide, in a culturable bacterium Salinispora arenicola is reported and nazumamide A is identified, a sponge-derived linear tetrapeptide currently used as a thrombin inhibitor, in Salinipora pacifica.
Abstract: Marine sponges are a major component of benthic communities and act as a reservoir for microbial species. In terms of biomass, they are the richest source of secondary metabolite production, with the potential to influence both benthic and pelagic systems. In most cases it is the sponge-associated microbes that account for many of the secondary metabolites assigned to the host. Here we report the occurrence of cycloaspeptide A, a fungus-derived cyclic peptide, in a culturable bacterium Salinispora arenicola. We have also identified nazumamide A, a sponge-derived linear tetrapeptide currently used as a thrombin inhibitor, in Salinispora pacifica. Their structures were determined using an integrated approach consisting of: (1) HPLC-UV-Vis-QToF-MS analysis with multimode ionization (ESI and APCI) and fast polarity switching; (2) database searching and matching of monoisotopic masses, retention times, mass spectra of the precursor and product ions of the compounds of interest and the authentic reference standards thereof.

10 citations


Journal ArticleDOI
TL;DR: It is found that two of the strains of Salinispora arenicola produced mevinolin, a fungus-derived cholesterol-lowering agent in the Great Barrier Reef region of Australia.
Abstract: Forty-five strains from two different species (Salinispora arenicola and Salinispora pacifica) were isolated from three different marine sponge species in the Great Barrier Reef region of Australia. We found that two of the strains of Salinispora arenicola (MV0335 and MV0029) produced mevinolin, a fungus-derived cholesterol-lowering agent. Compound structure was determined using an integrated approach: (a) high performance liquid chromatography-quadrupole time-of-flight-mass spectrometric analysis with multimode ionization (electrospray ionization and atmospheric pressure chemical ionization) and fast polarity switching; and (b) database searching and matching of monoisotopic masses, retention times and mass spectra of the precursor and product ions of the compounds of interest and the authentic reference standards thereof.

5 citations


Journal ArticleDOI
TL;DR: In this paper, an ansamycin, rifamycin W, and three phenylethylamides, N-(2'-phenylethyl)isobutyramide, 2-methyl-N-(2"-phenylethsyl)butyramides, and N-( 2'-phenylthyl)-isovaleramide were isolated from the fermentation broth of amarine actinomycete strain identified as Salinispora arenicola.
Abstract: An ansamycin, rifamycin W, and three phenylethylamides, N-(2'-phenylethyl)isobutyramide, 2-methyl-N-(2'-phenylethyl)butyramide, and N-(2'-phenylethyl)isovaleramide were isolated from the fermentation broth of amarine actinomycete strain identified as Salinispora arenicola. The structures of these compounds were confirmed by detailed interpretation of NMR spectroscopic and high resolution ESILC-MS data. Moderate antibacterial activity was observed for rifamycin W only.

4 citations