A study of three bacteria isolated from marine sediment and description of Micromonospora globispora sp. nov.

Abstract

During a study looking for the isolation of new actinobacteria strains with potential for antibiotic production from deep marine sediment, three strains were collected with a morphology similar to the one described for the Micromonospora genus. A polyphasic study was designed to determine the taxonomic affiliation of the strains S2901T, S2903, and S2904. All the strains showed chemotaxonomic properties in line with their classification in the genus Micromonospora, meso-diaminopimelic acid in the wall peptidoglycan, a tetrahydrogenated menaquinone with nine isoprene units as major respiratory quinone, iso-C15:0 and iso-C16:0 as major fatty acids and diphosphatidylglycerol, phosphatidylethanolamine and phosphatidylinositol as major polar lipids. The 16S rRNA gene sequences of strain S2901T, S2903, and S2904 showed the highest similarity (99.2%) with the type strain of Micromonospora halophytica DSM 43171T, forming an independent branch in the phylogenetic gene tree. Their independent position was confirmed with gyrB gene and MLSA phylogenies. Whole genome sequences confirmed by digital DNA-DNA hybridization analysis that the isolates should be assigned to a new species within the genus Micromonospora for which the name Micromonospora globispora sp. nov. (S2901T, S2903 and S2904) is proposed.