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Hemmati, R.

Publications and source records attributed to Hemmati, R..

2 recordsLinked to original sources

Genome sequence of Talaromyces trachyspermus, a biocontrol fungus isolated from broomrape

Applying antimicrobial compounds derived from microorganisms for plant disease management is one of the objectives of sustainable agriculture. The genus Talaromyces is known for its species ability to produce a diverse group of antimicrobial compounds. For example, T. trachyspermus has been reported to produce secondary metabolites, cell wall-degrading enzymes, and plant growth-promoting factors. Identification of novel promising metabolites and enzymes from T. trachyspermus is still in its infancy. Also, there is a lack of information about the genomic resources for its secondary metabolites and hydrolytic enzymes. Therefore, this study aimed to analyse the genome of a biocontrol isolate of this species to investigate its biocontrol mechanisms at the genomic level, focusing on secondary metabolites and cell wall degrading enzymes. The whole genome of T. trachyspermus isolate IRAN 3054C, obtained from necrotic Orobanch ramosa stems in Iran with biocontrol ability, was sequenced using the Illumina platform. We performed both de novo and resequencing analyses of the genome, obtaining a 31.3 Mb assembly. The abundance of protein groups associated with biocontrol activities was assessed in the studied genome. Fungismash was used to detect and annotate secondary metabolites. The analysis revealed the presence of several secondary metabolite biosynthesis gene clusters (BGCs), with a high frequency of polyketide synthases (T1PKS) and nonribosomal peptide synthetases (NRPS), which are known to produce bioactive compounds with antimicrobial properties. Among the identified secondary metabolites, Fusarin, YWA1, Dimethylcoprogen, and Squalestatin S1 exhibited the highest similarity to known compounds. Furthermore, sequences similar to Phyllostictine A/B and Cornexistin indicate potential herbicidal properties. The genome also had domains for enzymes involved in phosphate solubilisation, siderophore production, and fungal cell wall degradation, which are essential for biocontrol and plant growth promotion. Our findings highlight the genomic richness of T. trachyspermus IRAN 3054C for biocontrol. Further metabolomics studies are needed to validate the actual production of these secondary metabolites and explore their functional roles in biocontrol.

genomics↗

Expansion of a subset within C2 clade of Escherichia coli sequence type 131 (ST131) is driving the increasing rates of Aminoglycoside resistance: a molecular epidemiology report from Iran

The most important lineage of Escherichia coli, named sequence type 131 (ST131) is a pandemic clone which drives the increasing rates of antibiotic resistance. While the pervasiveness of ST131 clade C, especially subclades C2 and C1-M27 has been demonstrated in numerous global surveys, no report about the ST131 clades and its virotypes has been published from Iran, so far. So, in this study we investigated and compared the virotypes, antibiotic susceptibility patterns, resistance/virulence determinants and clonality of ST131 clades collected during one-year surveillance study. Most of isolates belonged to clade C2 (34/76 [44.7%]), with the highest virulence factor (VF) scores and resistance rates. The distinctive profiles of clade C2 virulence genes were revealed by "principle coordinates analysis" (PcoA) test. The distribution of hlyA/cnf1virulence genes among clade C2 was not uniform, so that positive strains showed significantly higher rates of resistance markers (blaCTX-M-15, blaOXA-1, aac6Ib/Ib-cr and aac3IIa) and ampicillin- sulbactam/gentamicin/tobramycin resistance. Virotype C as the most common virotype (48.7%) was predominant among clade C1 population, while almost all of virotypes E and F [(22/23), 95.6%] strains belonged to clade C2, with the highest VF scores and aminoglycoside resistance rates. "Multi locus variable Number tandem repeats analysis" (MLVA) clustered clades C1 and C2 together, while clades A and B strains were mostly identified as singletons. Appearance of virotypes E and F among clade C2 strains with higher rates of aminoglycoside resistance/virulence genes content demonstrate the shifting dynamics of this pandemic clone in response to antibiotic selection pressure by establishing the newly-emerged subsets.

microbiology↗