Testudinibacter Crocodili Sp. Nov., a New Member of the Family Pasteurellaceae Isolated from Crocodilians.

Five crocodilian species were investigated for the presence of Pasteurellaceae. A total of 27 pharyngeal isolates were obtained and characterized by MALDI-TOF MS and preliminary phenotypic tests to enable selection of representative strains for further genotypic characterization. Twelve isolates were selected for sequencing followed by phylogenetic analyses, digital DNA-DNA hybridization (dDDH) and calculation of average nucleotide identity (ANI), in addition to comparative analyses of partial rpoB, 16S rRNA gene sequences and further phenotypic characterization. The phenotypic and genotypic comparisons grouped the strains into three clades (clade 1: n=4; clade 2: n=3; clade 3: n=5). The clade 3 strains had a 16S rRNA gene sequence similarity ranging from 94.8 to 96.5%, a dDDH value of ≤48.7% and an ANI value of ≤92.6% to the closest relative, Testudinibacter aquarius ELNT2xT, and could be distinguished from all current Pasteurellaceae species by a combination of phenotypic traits. Our results indicate that the clade 3 strains should be classified as representatives of a new Testudinibacter species for which we suggest Testudinibacter crocodili sp. nov. The type strain of T. crocodili is Cuba42T (=CCUG 77853T=DSM 118260T) and was isolated in Denmark in 2018 from the pharynx of a captive Cuban crocodile (Crocodylus rhombifer).