Different Secondary Metabolite Profiles of Phylogenetically almost Identical Streptomyces griseus Strains Originating from Geographically Remote Locations

Abstract

As Streptomyces have shown an outstanding capacity for drug production, different campaigns in geographically distant locations currently aim to isolate new antibiotic producers. However, many of these newly isolated Streptomyces strains are classified as identical to already described species. Nevertheless, as discrepancies in terms of secondary metabolites and morphology are possible, we compared two Streptomyces strains with identical 16S rRNA gene sequences but geographically distant origins. Chosen were an Easter Island Streptomyces isolate (Streptomyces sp. SN25_8.1) and the next related type strain, which is Streptomyces griseus subsp. griseus DSM 40236T isolated from Russian garden soil. Compared traits included phylogenetic relatedness based on 16S rRNA gene sequences, macro and microscopic morphology, antibiotic activity and secondary metabolite profiles. Both Streptomyces strains shared several common features, such as morphology and core secondary metabolite production. They revealed differences in pigmentation and in the production of accessory secondary metabolites which appear to be strain-specific. In conclusion, despite identical 16S rRNA classification Streptomyces strains can present different secondary metabolite profiles and may well be valuable for consideration in processes for drug discovery.

Optimization of Streptomyces hygroscopicus Cultivation Parameters in a Lab‐scale Bioreactor

“…It is known that the sensitivity to antifungal components between isolates belonging to different species could be different 20. In accordance, the obtained results confirm the assumption that inhibition of tested phytopathogenic isolates is the result of synergistic action of diverse antifungal compounds produced by S. hygroscopicus 21.…”

Actinobacteria from Antarctica as a source for anticancer discovery

“…However, recent studies have found that discrepancies in terms of chemical and morphological features were possible in microorganisms belonging to same taxonomy, as determined for identical 16S rRNA gene sequences 54 . This finding was especially observed when studying bacteria from geographically distant origins or associated with different host species, in accordance to the ecovar concept [55][56][57] . Therefore, although the limitations of 16S rRNA gene have been widely recognized for screening of bioactive strains, we have assumed that the rhizosphere of D. antarctica could lead to high grade of specialism, with a lot of clonal populations.…”

Comparative Genomics Determines Strain-Dependent Secondary Metabolite Production in Streptomyces venezuelae Strains

“…Despite most of the smBGCs being conserved among the closely related S. venezuelae strains, the production of specific secondary metabolites—chloramphenicol and jadomycin—differed among the strains. The different secondary metabolite profiles of phylogenetically close strains were also reported in two S. griseus strains, which produced seven or four detectable strain-specific secondary metabolites [ 60 ]. By comparing the smBGCs sequences from the closely related strains, we revealed that ATCC 21113 could not produce chloramphenicol due to the single nucleotide deletion in the cmlI gene.…”