Streptomyces acidipaludis sp. nov., an actinobacterium isolated from peat swamp forest soil

An actinobacterium strain PLK6-54T was isolated from Lankwai peat swamp forest soil collected from Yala province, Thailand. Strain PLK6-54T exhibited morphological and chemotaxonomic properties described for the genus 
 
 Streptomyces
 
 . It formed a spiral spore chain directly on aerial mycelium. Growth was observed between 20 and 40 °C and at pH 5–8. The maximum NaCl for growth was 2 % (w/v). ll-Diaminopimelic acid, arabinose and ribose were detected in the whole-cell hydrolysate. Diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol, phosphatidylinositol and phosphatidylinositolmannoside were detected as the phospholipids. The major menaquinones were MK-10(H2) and MK-9(H6). The major cellular fatty acids were iso-C16 : 0, anteiso-C15 : 0 and iso-C14 : 0. 16S rRNA gene sequence data supported the assignment of strain PLK6-54T to the genus 
 
 Streptomyces
 
 and showed that 
 
 Streptomyces rubidus
 
 NBRC 102073T (99.0 %) was the closest relative. Moreover, the average nucleotide identity-blast (85.5 %) and digital DNA–DNA hybridization (30.7 %) values reported between strain PLK6-54T and its closest neighbour were below the threshold values for delineation of a novel species. Strain PLK6-54T could be distinguished from related validly described 
 
 Streptomyces
 
 species by several phenotypic properties. The combination of genotypic and phenotypic data indicated that strain PLK6-54T is representative of a novel species of the genus 
 
 Streptomyces
 
 . The name Streptomyces acidipaludis sp. nov. is proposed for strain PLK6-54T. The type strain is PLK6-54T (=TBRC 11250T=NBRC 114297T).