Ali H. Bahkali

Bio: Ali H. Bahkali is an academic researcher from King Saud University. The author has contributed to research in topics: Dothideomycetes & Pleosporales. The author has an hindex of 50, co-authored 287 publications receiving 9411 citations. Previous affiliations of Ali H. Bahkali include Yeungnam University & Landcare Research.

Occurrence and geographical distribution of mangrove fungi

Abstract: This is a multidimensional review of mangrove fungi occurring as saprobes, pathogens and endophytes of a wide range of host substrates and those isolated from the water columns and sediments in mangroves. Eight-hundred and fifty taxa including 658 that are supported by both morphology and molecular data and 192 with only morphological data are listed. These constitute Ascomycota, the dominant group with 773 species, and 58 Basidiomycota, one Blastocladiomycota, five Chytridiomycota, and 13 Mucoromycota. This study also includes data on mangrove yeasts 103 Ascomycota, 39 Basidiomycota and 193 taxa isolated from sediments. Endophytes isolated from submerged parts of mangrove plants total 38. The most specious orders of mangrove fungi are Pleosporales 133, Saccharomycetales 102, Microascales 101, Eurotiales 87, Hypocreales 60 and Xylariales 54. Speciose genera include Candida 39, Aspergillus 53, Penicillium 17 and Corollospora 16. The highest number of mangrove fungi have been recorded from the Pacific Ocean 553, which is the largest ocean, followed by Indian 408 and Atlantic Oceans 259. Geographical distribution of mangrove fungi varied from ocean to ocean with only 109 taxa common to the Atlantic, Indian and Pacific Oceans. Of the various countries reported for mangrove fungi, India accommodates the highest number (339) followed by Thailand 303, Malaysia 171, Florida Everglades, USA 134 and Brunei 134. A total of 60 different mangrove plants and their associates have been surveyed for mangrove fungi. These results are discussed and compared with previous studies.

Pseudogenization in pathogenic fungi with different host plants and lifestyles might reflect their evolutionary past

Abstract: Pseudogenes are genes with significant homology to functional genes but contain disruptive mutations (DMs) leading to production of non- or partially functional proteins. Little is known about pseudogenization in pathogenic fungi with different lifestyles. Here we report on identification of DMs causing pseudogenes in the genomes of the fungal plant pathogens Botrytis cinerea, Cladosporium fulvum, Dothistroma septosporum, Mycosphaerella fijiensis, Verticillium dahliae and Zymoseptoria tritici. In these fungi we have identified 1740 gene models containing 2795 DMs obtained by an alignment-based gene prediction method. The contribution of sequencing errors to DMs was minimized by analyses of resequenced genomes to obtain a refined data set of 924 gene models containing 1666 true DMs. The frequency of pseudogenes varied from 1 to 5% in the gene catalogues of these fungi, being the highest in the asexually reproducing fungi C. fulvum (4.9%), followed by D. septosporum (2.4%) and V. dahliae (2.1%). The majority of pseudogenes does not represent recent gene duplications, but members of multi-gene families and unitary genes. In general there was no bias for pseudogenization of specific genes in the six fungi. Single exceptions are those encoding secreted proteins including proteases which appeared more frequently pseudogenized in C. fulvum than in D. septosporum. Most pseudogenes present in these two phylogenically closely related fungi are not shared suggesting that they are related to adaptation to a different host (tomato versus pine) and lifestyle (biotroph versus hemi-biotroph)

Molecular taxonomy and morphological characterization reveal new species and new host records of Torula species (Torulaceae, Pleosporales)

Abstract: Four new species and two new host records of Torula (Torulaceae, Pleosporales) are described and illustrated from herbaceous litter collected in Italy and Thailand. The new species possess colony, conidiophore and conidial characteristics that fit within the generic concept of Torula. Detailed morphological observations clearly demarcate four of these from extant species and are hence described as new (Torula chiangmaiensis sp. nov., Torula pluriseptata sp. nov., Torula chromolaenae sp. nov., Torula mackenziei sp. nov.). Details of asexual morphs are described, and justifications for establishing these new species are provided. The nuclear are sequenced ribosomal RNA genes as well as protein coding genes to infer phylogenetic relationships and discuss phylogenetic affinities with morphologically similar species. Our morphological distinction is further supported by phylogenetic discrimination. In particular, phylogenies depict a close relationship of Torula chiangmaiensis and T. pluriseptata to T. hollandica, while T. chromolaenae and T. mackenziei constitute an independent phylogenetic lineage basal to T. herbarum and T. ficus. Torula ficus and T. masonii are also described and their phylogeny investigated as new host records from Bidens pilosa and Iris germanica, respectively.

New saprobic marine fungi and a new combination

Abstract: Abstract This paper documents five new saprobic marine fungi occurring on various substrata in the marine environment. Bacusphaeria nypae gen. et sp. nov. was discovered on bases of fronds of Nypa fruticans in Malaysia and phylogenetically, it belongs to the Tirisporellaceae (Tirisporellales, Diaporthomycetidae, Sordariomycetes) based on 18S and 28S rDNA. Cryptovalsa avicenniae, Ceriosporopsis minuta and Jattaea mucronata also belong to the Sordariomycetes; Cr. avicenniae was saprobic on Avicennia marina collected in Saudi Arabia, J. mucronata on intertidal decaying bark of Rhizophora mucronata while Ce. minuta was found on driftwood collected on a sandy beach in Japan. Phylogeny based on 18S and 28S rDNA placed Cr. avicenniae with other Cryptovalsa species in the Diatrypaceae. Jattaea mucronata groups well in the Calosphaeriales and is closely related to J. algeriensis based on a phylogeny using ITS and 28S rRNA and RPB2 genes. Aegeanispora elanii gen. et sp. nov. is an asexual fungus which produces pycnidia on decaying driftwood collected in the Aegean Sea. Combined 18S and 28S rDNA phylogenetic analyses suggest that it is a member of the Pleosporales, Dothideomycetes. Ceriosporopsis minuta resembles C. capillacea with its tubular, long polar appendages of ascospores but dimensions of ascomata and ascospores for the former species are considerably smaller. Ceriosporopsis is considered the best genus to accommodate C. minuta without support from sequence data. Sammeyersia is established as a new genus to accommodate Lulworthia grandispora, a species unrelated to Lulworthia fucicola, the type species. The diagnostic characteristic for the genus is a melanized region at the base of the neck of the ascomata.

A new species

Abstract: We redescribe the only previously known species of Myrsidea from bulbuls, M. pycnonoti Eichler. Sixteen new species are described; they and their type hosts are: M. phillipsi ex Pycnonotus goiavier goiavier (Scopoli), M. gieferi ex P. goiavier suluensis Mearns, M. kulpai ex P. flavescens Blyth, M. finlaysoni ex P. finlaysoni Strickland, M. kathleenae ex P. cafer (L.), M. warwicki ex Ixos philippinus (J. R. Forster), M. mcclurei ex Microscelis amaurotis (Temminck), M. zeylanici ex P. zeylanicus (Gmelin), M. plumosi ex P. plumosus Blyth, M. eutiloti ex P. eutilotus (Jardine and Selby), M. adamsae ex P. urostictus (Salvadori), M. ochracei ex Criniger ochraceus F. Moore, M. borbonici ex Hypsipetes borbonicus (J. R. Forster), M. johnsoni ex P. atriceps (Temminck), M. palmai ex C. ochraceus, and M. claytoni ex P. eutilotus. A key is provided for the identification of these 17 species.

Ab initio calculation of vibrational absorption and circular dichroism spectra using density functional force fields

Abstract: : The unpolarized absorption and circular dichroism spectra of the fundamental vibrational transitions of the chiral molecule, 4-methyl-2-oxetanone, are calculated ab initio. Harmonic force fields are obtained using Density Functional Theory (DFT), MP2, and SCF methodologies and a 5S4P2D/3S2P (TZ2P) basis set. DFT calculations use the Local Spin Density Approximation (LSDA), BLYP, and Becke3LYP (B3LYP) density functionals. Mid-IR spectra predicted using LSDA, BLYP, and B3LYP force fields are of significantly different quality, the B3LYP force field yielding spectra in clearly superior, and overall excellent, agreement with experiment. The MP2 force field yields spectra in slightly worse agreement with experiment than the B3LYP force field. The SCF force field yields spectra in poor agreement with experiment.The basis set dependence of B3LYP force fields is also explored: the 6-31G* and TZ2P basis sets give very similar results while the 3-21G basis set yields spectra in substantially worse agreements with experiment. jg

A European Database of Fusarium graminearum and F. culmorum Trichothecene Genotypes

Abstract: Fusarium species, particularly Fusarium graminearum and F. culmorum, are the main cause of trichothecene type B contamination in cereals. Data on the distribution of Fusarium trichothecene genotypes in cereals in Europe are scattered in time and space. Furthermore, a common core set of related variables (sampling method, host cultivar, previous crop, etc.) that would allow more effective analysis of factors influencing the spatial and temporal population distribution, is lacking. Consequently, based on the available data, it is difficult to identify factors influencing chemotype distribution and spread at the European level. Here we describe the results of a collaborative integrated work which aims (1) to characterize the trichothecene genotypes of strains from three Fusarium species, collected over the period 2000–2013 and (2) to enhance the standardization of epidemiological data collection. Information on host plant, country of origin, sampling location, year of sampling and previous crop of 1147 F. graminearum, 479 F. culmorum, and 3 F. cortaderiae strains obtained from 17 European countries was compiled and a map of trichothecene type B genotype distribution was plotted for each species. All information on the strains was collected in a freely accessible and updatable database (www.catalogueeu.luxmcc.lu), which will serve as a starting point for epidemiological analysis of potential spatial and temporal trichothecene genotype shifts in Europe. The analysis of the currently available European dataset showed that in F. graminearum, the predominant genotype was 15-acetyldeoxynivalenol (15-ADON) (82.9%), followed by 3-acetyldeoxynivalenol (3-ADON) (13.6%), and nivalenol (NIV) (3.5%). In F. culmorum, the prevalent genotype was 3-ADON (59.9%), while the NIV genotype accounted for the remaining 40.1%. Both, geographical and temporal patterns of trichothecene genotypes distribution were identified.