Agromyces aerolatus sp. nov., an Actinobacterium Isolated from Air of Manufacturing Shop in a Pharmaceutical Factory.

Abstract

Two Gram-stain-positive, aerobic, rod-shaped bacterial strains without flagellum, designated strains LY-1074 ^T and LY-1358, were isolated from a settling dish in manufacturing shop of a pharmaceutical factory in Shandong province, China. Both strains grew under aerobic conditions with temperature of 10-37 °C (optimal 28 °C), pH of 6.0-10.0 (optimal 8.0) and NaCl concentration of 0-3.0% (w/v) (optimal 0-1.0%). Both strains showed the highest 16S rRNA gene sequence similarity to strain Agromyces indicus NIO-1018 ^T, severally with the similarity of 97.5% and 98.0%, and phylogenetic analysis based on 16S rRNA gene sequences indicated that strains LY-1074 ^T and LY-1358 had clear and independent taxonomic positions in the genus Agromyces. Chemotaxonomic analysis indicated that the main respiratory quinone of the two strains was MK-12, the major fatty acids were anteiso-C_15:0, iso-C_15:0, iso-C_16:0 and anteiso-C_17:0, and the major polar lipids consisted of diphosphatidylglycerol (DPG), phosphatidylglycerol (PG) and unidentified glycolipid (GL). The G + C contents of strains LY-1074 ^T and LY-1358 were both 71.0%. Strains LY-1074 ^T and LY-1358 demonstrated 100% digital DNA-DNA hybridization (dDDH) and average nucleotide identity (ANI) values, unequivocally establishing their genomic conspecificity. In contrast, comparative genomic analysis against all available Agromyces genomes revealed significantly lower ANI and dDDH values (below the interspecific thresholds of 95% and 70%, respectively). According to the phenotypic, chemotaxonomic and phylogenetic features, strains LY-1074 ^T and LY-1358 were considered to represent a novel species, for which the name Agromyces aerolatus sp. nov. is proposed. The type strain is strain LY-1074 ^T (= GDMCC 1.60117 ^T = JCM 36371 ^T).