Agromyces badenianii sp. nov., isolated from plateau pika (Ochotona curzoniae)

Abstract

Two aerobic, Gram-stain-positive, catalase-positive, non-motile and rod-shaped bacterial strains, designated MF30-A^T and MF845, were isolated from the intestinal contents of plateau pika collected from the Qinghai-Tibet Plateau. Optimal growth of these two strains was observed under aerobic conditions at pH 7.0 and 28 °C. The 16S rRNA gene sequences of the isolates had highest similarities of 98.5 and 98.4 % to Agromyces fucosus, respectively. In the 16S rRNA gene and polygenetic trees, strains MF30-A^T and MF845 were clearly distinct from other species. The two strains could not produce acid from arbutin, d-fructose, D-sucrose, glycogen, salicin or starch. Production of β-glucosidase by these strains was negative. The major fatty acids of these strains were anteiso-C_{15 : 0}, anteiso-C_{17 : 0} and iso-C_{16 : 0}. Strain MF30-A^T contained galactose, rhamnose and ribose as cell wall sugars and MK-12 and MK-11 as predominant menaquinones. The major polar lipids in strain MF30-A^T were diphosphatidylglycerol, phosphatidylglycerol and a glycolipid, while the peptidoglycan contained alanine, glutamic acid, glycine and 2,4-diaminobutyric acid. The G+C contents of the DNA of strains MF30-A^T and MF845 were 69.8 mol% and 69.7 mol%, respectively. The average nucleotide identity and digital DNA-DNA relatedness values of the two strains with all available genomes of the genus Agromyces were far below the respective thresholds of 95 and 70 %, respectively. All genotypic and phenotypic data indicated that strains MF30-A^T and MF845 should be classified as novel members of the genus Agromyces, for which the name Agromyces badenianii sp. nov. is proposed. The type strain is MF30-A^T (=CGMCC 1.16469^T=DSM 106183^T).

Keywords: Agromyces badenianii; novel species; plateau pika.