Phylogenetic appraisal of antagonistic, slow growing actinomycetes isolated from hypersaline inland solar salterns at Sambhar salt Lake, India

Abstract

Inland solar salterns established in the vicinity of Sambhar Lake are extreme saline environments with high salinity and alkalinity. In view of the fact that microbes inhabiting such extreme saline environments flourish the contemporary bioprospecting, it was aimed to selectively isolate slow growing and rare actinomycetes from the unexplored solar salterns. A total of 14 slow growing actinomycetes were selectively isolated from three composite soil samples of inland solar salterns. Among the isolates, four groups were formed according to similarity of the banding patterns obtained by amplified ribosomal DNA restriction analysis (ARDRA). A subset of representative isolates for each ARDRA group was identified using 16S rDNA sequence based phylogenetic analysis and subsequently the entire isolates were assigned under three different genera; Streptomyces, Pseudonocardia, and Actinoalloteichus. The genus Streptomyces was found to be the dominant among the isolates. Furthermore, rare actinomycete genus Actinoalloteichus was isolated for the first time from solar saltern. Determination of salt-tolerance revealed that certain level of salt-tolerance and moderate halophilism occurs among the actinomycetes isolated from the inland salterns. In addition, all the acinomycetes were screened in two levels to unravel their ability to produce antimicrobial compounds. Significant antimicrobial activity was found among the actinomycetes against a range of bacteria and fungi to worth further characterization of these persuasive actinomycetes and their antimicrobial secondary metabolites. In a nutshell, this study offered a first interesting insight on occurrence of antagonistic rare actinomycetes and streptomycetes in inland solar salterns associated with Sambhar salt Lake.

Non-streptomycete actinomycetes nourish the current microbial antibiotic drug discovery

“…Numerous rare actinomycetes have been isolated from variety of soil samples (Seong et al, 2001; Gu et al, 2007; Li et al, 2007, 2010; Ara et al, 2013), plant materials (Qin et al, 2009; Janso and Carter, 2010; Zhao et al, 2011), marine sources (Zhang et al, 2006; Sun et al, 2010; Radhakrishnan et al, 2011; Goodfellow et al, 2012), extreme saline zones (Jose and Jebakumar, 2013), Volcanic zones (Lee and Lee, 2011) hyper arids (Okoro et al, 2009), glaciers (Reddy et al, 2010; Zhang et al, 2012), and much more. As a result, an array of rare actinomycetes available for current antimicrobial drug screening programs has increased.…”

Diversity of actinobacteria in the marshes of Ezzemoul and Djendli in northeastern Algeria

“…Studies have reported that members of the genus Nocardiopsis were predominant in some desert soils in Algeria (Meklat et al 2011) and in saline soil in China (Lv et al 2006). Those of the genus Streptomyces were predominant in other saline soils in China (Cai et al 2009) and in India (Jose and Jebakumar 2013). Rhodococcus species can occupy several habitats such as soil, water, air, plants, and animals.…”

An Implication of Actinomycetes on Human Well-Being: A Review

“…In recent times, much care has been given to isolating rare actinomycetes from diverse previously unexplored common as well as uncommon extreme environments. Numerous rare actinomycetes have been isolated from variety of soil samples [31; 47-50], plant materials [51][52][53], marine sources [54][55][56][57], extreme saline zones [58], volcanic zones [59], hyper arids [60], glaciers [61,62], and much more. Therefore, a variety of uncommon actinomycetes accessible for current antimicrobial medication screening programs has increased.…”