Abstract
Three rod-shaped, Gram-stain-positive, and catalase-positive, phenotypically closely related isolates (HY052(T), HY050, and HY045) were obtained from fecal samples collected from bats in Guangxi province and Chongqing city of China. Circular, smooth, light-yellow colonies appeared on brain heart infusion plate after 24-48 h incubation at 28°C. The optimal pH for growth was between 6.0 and 7.5. Based on 16S rRNA, the three isolates were phylogenetically related to Agromyces terreus DS-10(T), Agromyces aureus AR33(T), Agromyces salentinus 20-5(T), Agromyces allii UMS-62(T), Agromyces lapidis CD55(T), and Agromyces italicus CD1(T). Moreover, based on 296 core genes, the phylogenomic tree indicated that the three isolates clustered together, closest to Agromyces cerinus VKM Ac-1340(T) and Agromyces fucosus VKM Ac-1345(T) but separated distantly from other Agromyces species. The average nucleotide identity values between strain HY052(T) and other Agromyces species ranged from 79.3% to 87.9%, lower than the 95-96% threshold. Furthermore, the genome of strain HY052(T) contains a circular chromosome of 3,437,203 bp with G + C content of 69.0 mol%. Main fatty acids were anteiso-C(15:0) and anteiso-C(17:0). The polar lipids comprised diphosphatidylglycerol, phosphatidylglycerol, and unidentified glycolipids. Rhamnose, ribose, and glucose were the primary cell wall sugars. The major peptidoglycan amino acids included alanine, glutamic acid, glycine, and 2,4-diaminobutyric acid. An additional remarkable difference from other Agromyces species is that MK-12 was the sole menaquinone in strain HY052(T). Based on results from the polyphasic characterizations performed in this study, our isolates are proposed to be members of a novel species in genus Agromyces, named Agromyces laixinhei. The type strain is HY052(T) (= CGMCC 1.17175(T) = JCM 33695(T)).