Classification of three corynebacterial strains isolated from the Northern Bald Ibis ( Geronticus eremita ): proposal of Corynebacterium choanae sp. nov., Corynebacterium pseudopelargi sp. nov., and Corynebacterium gerontici sp. nov.

Three Gram-stain-positive, rod-to-coccoid-shaped, catalase-positive and non-motile bacterial strains isolated from the choanae of a Northern bald ibis, designated strains 200CH ^T , W8 ^T and 812CH ^T , respectively, were subjected to comprehensive taxonomic characterization. The three strains were oxidase-negative. The 16S rRNA gene sequence of 200CH ^T showed highest similarities to Corynebacterium epidermidicanis 410 ^T (96.7 %) followed by Corynebacterium argentoratense DSM 44202 ^T , Corynebacterium ulcerans NCTC 7910 ^T and Corynebacterium pseudotuberculosis CIP 102968 ^T (each 96.3 %). Strains W8 ^T and 812CH ^T both showed highest 16S rRNA gene sequence similarities to Corynebacterium pelargi 136/3 ^T (98.0 and 99.9 %, respectively). Comparison of the partial housekeeping gene sequence of fusA showed higher sequence similarities of 812CH ^T to C. pelargi (95.8 %) than W8 ^T (90.9 %) which was also confirmed by corresponding amino acid sequences. In both, fusA gene and corresponding protein sequence strain 200CH ^T showed low sequence similarities to C. epidermidicanis 410 ^T (81.6 and 87.4 %, respectively). Strains 812CH ^T and W8 ^T had 76.7 % ANI similarity to each other and 88.2 and 76.4 % to C. pelargi 136/3 ^T , respectively. In silico DNA-DNA hybridization values for 812CH ^T and W8 ^T were 22.1 % among the two strains and 35.3 and 21.7 % to C. pelargi 136/3 ^T , respectively. These data not only demonstrate that strain W8 ^T is a representative of a novel species, but despite the high 16S rRNA gene sequence similarity to C. pelargi , strain 812CH ^T is also a representative of another novel species. All three strains possessed corynemycolic acids and contained meso -diaminopimelic acid as the diagnostic diamino acid of the peptidoglycan. The two strains, 200CH ^T and W8 ^T , are distinguished from each other and established Corynebacterium species phylogenetically and phenotypically. In conclusion, three novel species of the genus Corynebacterium are proposed, namely Corynebacteriumpseudopelargi 812CH ^T (=LMG 30627 ^T =CCM 8832 ^T ) , Corynebacterium choanae 200CH ^T (=LMG 30628 ^T =CCM 8831 ^T ) and Corynebacteriumgerontici W8 ^T (=LMG 30629 ^T =CCM 8833 ^T ), respectively.