Streptomyces siamensis sp. nov., and Streptomyces similanensis sp. nov., isolated from Thai soils

Abstract

Three actinomycete strains, KC-038(T), KC-031 and KC-106(T), were isolated from soil samples collected in the southern Thailand. The morphological and chemotaxonomic properties of strains KC-038(T), KC-031 and KC-106(T) were consistent with the characteristics of members of the genus Streptomyces, that is, the formation of aerial mycelia bearing spiral spore chains; the presence of LL-diaminopimelic acid in the cell wall, MK-9 (H6), MK-9 (H4) and MK-9 (H8) as the predominant menaquinones; and C16:0, iso-C16:0 and anteiso-C15:0 as the major cellular fatty acids. 16S rRNA gene sequence analyses indicated that strains KC-038(T) and KC-031 were highly similar (99.9%), and they were closely related to S. olivochromogenes NBRC 3178(T) (98.1%) and S. psammoticus NBRC 13971(T) (98.1%). Strain KC-106(T) was closely related to S. seoulensis NBRC 16668(T) (98.9%), S. recifensis NBRC 12813(T) (98.9%), S. chartreusis NBRC 12753(T) (98.7%) and S. griseoluteus NBRC 13375(T) (98.4%). The values of DNA-DNA relatedness between the isolates and the type strains of the related species were below 70%. On the basis of the polyphasic evidence, the isolates should be classified as two novel species, namely Streptomyces siamensis sp. nov. (type strain, KC-038(T) = NBRC 108799(T) = PCU 328(T) = TISTR 2107(T)) and Streptomyces similanensis sp. nov. (type strain, KC-106(T) = NBRC 108798(T) = PCU 329(T) = TISTR 2104(T)).

Dimeric Pimprinine Alkaloids From Soil-Derived Streptomyces sp. NEAU-C99

“…Natural products, in particular secondary metabolites derived from actinomycetes, Gram-positive bacteria (Hoshino et al, 2018;Yang et al, 2018), such as antibiotics, enzymes, enzyme inhibitors, and other pharmacologically active agents (Sripreechasak et al, 2013), have contributed substantially to modern medical care (Onaka, 2017). These microbial natural products are still an attractive and indispensable resources for drug discovery due to their potential productivity of unique core skeletons, such as the antiparasitic drug ivermectin (Cragg and Newman, 2013) and the anticancer agent eribulin (Yu et al, 2011).…”

Antimicrobial biosynthetic potential and diversity of culturable soil actinobacteria from forest ecosystems of Northeast India

“…Additionally, it also contains sodium propionate which makes it most suitable for the isolation of actinobacteria because it acts as an antifungal agent 19 . The use of amending the isolation media with amphotericin B and rifampicin has been confirmed to be a good strategy for promotion of growth of slow growing actinobacteria in the absence of fast growing contaminants 19,33,34 . www.nature.com/scientificreports www.nature.com/scientificreports/ Morphological differentiation of all the 107 actinobacteria was done based on their colony morphology, aerial and substrate mycelium colour and diffusible pigment production.…”

Exploring the Potential of Antibiotic Production From Rare Actinobacteria by Whole-Genome Sequencing and Guided MS/MS Analysis

“…They are listed in Table 2 together with their reference strains and corresponding 16S rRNA gene sequence similarity percentages. Applying the 97.0% similarity threshold widely used for novel bacterial species identification ( Sripreechasak et al, 2013 ; Kim et al, 2014 ) as a reference, there were seven isolates considered highly similar to their reference strains (similarity > 99%), 6 isolates considered closely related to their reference strains (similarity > 98%), and 1 isolate considered between closely related to and related to its reference strain (similarity = 98%). In terms of genus diversity, Streptomyces was the dominant one harboring six strains, followed by Microbacterium with three strains, and Kineococcus with two strains.…”