Streptomyces marianiisp. nov., a novel marine actinomycete from southern coast of India

A novel marine actinomycete strain designated ICN19(T)was isolated from the subtidal sediment of Chinnamuttam coast of Kanyakumari, India and subjected to polyphasic taxonomic analysis. Neighbour-joining tree based on 16S rRNA gene sequences of validly described type strains had revealed the strain ICN19(T)formed distinct cluster withStreptomyces wuyuanensisCGMCC 4.7042(T),Streptomyces tirandamycinicusHNM0039(T)andStreptomyces spongiicolaHNM0071(T). Morphological, physiological and chemotaxonomic characteristics were consistent with those of members of the genusStreptomyces. The strain possessedll-diaminopimelic acid as the diagnostic diamino acid. The predominant isoprenoid quinone was identified as MK-9(H8) (70%), MK-9(H6) (20%) and MK-9(H2) (2%), with the major cellular fatty acids (>10%) beinganteiso-C-15:0, C(16:0)andiso-C-16:0. The main polar lipids were found to be diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, phosphatidylinositol mannosides and three unidentified phospholipids. The dendrogram generated on the basis of MALDI-TOF mass spectra supports the strain differentiated from its neigbours. The genome sequence of strain ICN19(T)was 9,010,366 bp in size with a total of 7420 protein-coding genes and 98 RNA genes. The genomic G+C content of the novel strain was 71.27 mol%. The DNA-DNA relatedness between strain ICN19(T)and the reference strains withS. wuyuanensisCGMCC 4.7042(T),S. tirandamycinicusHNM0039(T)andS. spongiicolaHNM0071(T)were 42.8%, 39.5% and 38%, respectively. Based on differences in physiological, biochemical, chemotaxonomic differences and whole-genome characteristics the isolated strain represents a novel species of the genusStreptomyces, for which the nameStreptomyces marianiisp. nov. is proposed. Type strain is ICN19(T)(=MCC 3599(T) = KCTC 39749(T)).

Automated summary

A novel marine actinomycete strain ICN19(T) was isolated and identified, showing distinct differences from previously described Streptomyces species at both phenotypic and molecular levels. The strain represents a new species within the genus Streptomyces based on physiological, biochemical, chemotaxonomic, and genomic characteristics. The proposed name for this novel species is Streptomyces marianii sp. nov. (ICN19(T) = MCC 3599(T) = KCTC 39749(T)).