Streptomyces asenjonii sp. nov., isolated from hyper-arid Atacama Desert soils and emended description of Streptomyces viridosporus Pridham et al. 1958

David P. Labeda,Roselyn Brown,Maria del Carmen Montero-Calasanz,Hamidah Idris,Imen Nouioui,Byung-Yong Kim,Alan T. Bull,Michael Goodfellow,Kanungnid Busarakam,Barbara A. Andrews

doi:10.1007/s10482-017-0886-7

Abstract

A polyphasic study was undertaken to establish the taxonomic status of Streptomyces strains isolated from hyper-arid Atacama Desert soils. Analysis of the 16S rRNA gene sequences of the isolates showed that they formed a well-defined lineage that was loosely associated with the type strains of several Streptomyces species. Multi-locus sequence analysis based on five housekeeping gene alleles showed that the strains form a homogeneous taxon that is closely related to the type strains of Streptomyces ghanaensis and Streptomyces viridosporus. Representative isolates were shown to have chemotaxonomic and morphological properties consistent with their classification in the genus Streptomyces. The isolates have many phenotypic features in common, some of which distinguish them from S. ghanaensis NRRL B-12104T, their near phylogenetic neighbour. On the basis of these genotypic and phenotypic data it is proposed that the isolates be recognised as a new species within the genus Streptomyces, named Streptomyces asenjonii sp. nov. The type strain of the species is KNN35.1bT (NCIMB 15082T = NRRL B-65050T). Some of the isolates, including the type strain, showed antibacterial activity in standard plug assays. In addition, MLSA, average nucleotide identity and phenotypic data show that the type strains of S. ghanaensis and S. viridosporus belong to the same species. Consequently, it is proposed that the former be recognised as a heterotypic synonym of the latter and an emended description is given for S. viridosporus.

Highlights

The prospect of isolating novel filamentous actinobacteria that synthesise new specialised metabolites is enhanced when bioprospecting strategies are focused on neglected and unexplored habitats (Hong et al 2009; Tiwari and Gupta 2012; Guo et al 2015), including desert soils (Meklat et al 2011; Boubetra et al 2013)
Polyphasic taxonomic studies on dereplicated actinobacteria isolated from hyper-arid and extreme hyper-arid Atacama Desert soils have led to the description of novel species of Lechevalieria (Okoro et al 2010), Lentzea (Idris et al 2017a) and Modestobacter (Busarakam et al 2016a) and to the detection of rare thermophilic Amycolatopsis species (Busarakam et al 2016b)
The present study was designed to establish the taxonomic position of several closely related Atacama Desert streptomycetes. These strains were the subject of a polyphasic taxonomic study which showed that they belong to a new species, Streptomyces asenjonii sp. nov

Summary

Introduction

The prospect of isolating novel filamentous actinobacteria that synthesise new specialised metabolites is enhanced when bioprospecting strategies are focused on neglected and unexplored habitats (Hong et al 2009; Tiwari and Gupta 2012; Guo et al 2015), including desert soils (Meklat et al 2011; Boubetra et al 2013).

Results

Conclusion