Draft Genome Sequencing of Microcoleus sp. HI-ES Isolated from Freshwater in Iraq: Cyanobacterial Strain

Abstract

Background: Cyanobacteria are a widely dominated group of microorganisms in nature that produce a diverse range of metabolites. Whilst the enormous number of bacterial genomes has deposited in the public databases, the number of cyanobacterial genomes remains limited. Aims: This study aimed to sequence the whole genome of an Iraqi cyanobacterium isolate, designed as Microcoleus sp. HI-ES. Methods: Microcoleus sp. HI-ES was isolated from a freshwater sample collected from the Mosul Dam lake. GB-11 liquid medium was used for primary isolation whereas agarose-GB-11 medium supplemented with lysozyme (100 µg/ml), imipenem (100 µg/ml), streptomycin (100 µg/ml), and cycloheximide (20 µg/ml) was used to obtain an axenic Microcoleus sp. HI-ES culture. Specialized bioinformatics tools were used for genome assembly, annotation, whole genome-based taxonomy analysis, in silico whole genome DNA-DNA hybridization (isDDH), and biosynthetic gene clusters (BGCs) detection. Results: The results showed that Microcoleus sp. HI-ES genome consists of 4,671,230 bp with a GC content of 47.7% distributed within 6417 contigs and a total of 6264 coding sequences. The whole genome-based phylogeny and isDDH values showed that Microcoleus sp. HI-ES is closed to the type strains: Microcoleus asticus IPMA8, Microcoleus vaginatus PCC 9802, M. vaginatus FGP-2, and Oscillatoria nigroviridis PCC 7112 with isDDH values of 61.7%, 59.8%, 59.8%, and 54.5%, respectively. Ten secondary metabolite BGCs were predicted in Microcoleus sp. HI-ES including four nonrobosomal peptides (NRPs) such as one NRPs, two resorcinol, two terpenes, and one T1PKS. The draft genome sequence of Microcoleus sp. HI-ES has been deposited at DDBJ/ENA/GenBank under the accession number JAPTMT000000000. Conclusion: The contribution of the depositing of the whole genome sequencing of Microcoleus sp. HI-ES, an Iraqi cyanobacterial strain, in public genbank databases will benefit the scientific community to understanding the potential of this cyanobacterial strain as a promising natural product producer.