Isolation and characterization of tick-borne Roseomonas haemaphysalidis sp. nov. and rodent-borne Roseomonas marmotae sp. nov.

Four novel Gram-negative, mesophilic, aerobic, motile, and cocci-shaped strains were isolated from tick samples (strains 546 and 573) and respiratory tracts of marmots (strains 1318 and 1311). The 16S rRNA gene sequencing revealed that strains 546 and 573 were 97.8% identical to Roseomonas wenyumeiae Z23, whereas strains 1311 and 1318 were 98.3% identical to Roseomonas ludipueritiae DSM 14915. In addition, a 98.0% identity was observed between strains 546 and 1318. Phylogenetic and phylogenomic analyses revealed that strains 546 and 573 clustered with R. wenyumeiae Z23, whereas strains 1311 and 1318 grouped with R. ludipueritiae DSM 14915. The average nucleotide identity between our isolates and members of the genus Roseomonas was below 95%. The genomic G+C content of strains 546 and 1318 was 70.9% and 69.3%, respectively. Diphosphatidylglycerol (DPG) and phosphatidylethanolamine (PE) were the major polar lipids, with Q-10 as the predominant respiratory quinone. According to all genotypic, phenotypic, phylogenetic, and phylogenomic analyses, the four strains represent two novel species of the genus Roseomonas, for which the names Roseomonas haemaphysalidis sp. nov. and Roseomonas marmotae sp. nov. are proposed, with 546 (= GDMCC 1.1780 = JCM 34187) and 1318 (= GDMCC 1.1781 = JCM 34188) as type strains, respectively.