Campylobacter molothri sp. nov. isolated from wild birds

Twenty-nine hippuricase-positive <i>Campylobacter</i> strains were isolated from wild birds and river water. Previous characterization using <i>atpA</i> typing indicated that these strains were related to <i>Campylobacter jejuni</i> and <i>Campylobacter coli</i> but were most similar to three recently described hippuricase-positive <i>Campylobacter</i> species recovered from zebra finches, i.e. <i>C. aviculae</i>, <i>C. estrildidarum</i> and <i>C. taeniopygiae</i>. Phylogenetic analyses using 330 core genes placed the 29 strains into a clade well separated from the other <i>Campylobacter</i> taxa, indicating that these strains represent a novel <i>Campylobacter</i> species. Pairwise digital DNA-DNA hybridization and average nucleotide identity values were below 70 and 95 %, respectively, thus providing further supporting evidence of a novel taxon. Standard phenotypic testing was performed. All strains are microaerobic or anaerobic, motile, Gram-negative, spiral cells that are oxidase, catalase and nitrate reductase positive, but urease negative. Genomic analyses indicate that the 29 strains can potentially synthesize very few amino acids <i>de novo</i> and are auxotrophic for many amino acids and cofactors, similar to the species composing the <i>Campylobacter lari</i> group. In addition, these strains encode complete Entner-Doudoroff and Leloir pathways, suggesting that they may possess the ability to utilize both glucose and galactose; these pathways were also identified in the genomes of the zebra finch-associated taxa. The data presented here show that these strains represent a novel species within <i>Campylobacter</i>, for which the name <i>Campylobacter molothri</i> sp. nov. (type strain RM10537^T=LMG 32306^T=CCUG 75331^T) is proposed.