Corynebacterium suedekumii sp. nov and Corynebacterium breve sp. nov., isolated from raw cow's milk

Four Gram-positive, rod-shaped, none-sporeforming, non-motile isolates were obtained from various raw milk samples taken from the cooling tank on a research farm in Königswinter, Germany. Based on phylogenetic analysis of the 16S rRNA genes and whole genome sequences, all isolates were assigned to the genus Corynebacterium, but were divided in two different groups. All isolates contained C_18 : 1 cis 9 and C_16 : 0 as predominant fatty acids, as well as traces of C_18 : 0. They all contained menaquinones MK-8 (H₂) and MK-9 (H₂) and produced mycolic acids characteristic for the majority of species belonging to the genus Corynebacterium. 16S rRNA gene sequence similarity values to the closest related type strains Corynebacterium humireducens DSM 45392^T and Corynebacterium pilosum DSM 20521^T were below 98.7 %, average nucleotide identity values were below 86 % and digital DNA-DNA-hybridization values were below 25 %, indicating that the isolates represent two novel species. The names Corynebacterium suedekumii sp. nov. and Corynebacterium breve sp. nov. are proposed, represented by the type strains LM112^T (=DSM 116216^T=HAMBI 3782^T) and R4^T (=DSM 116183^T=HAMBI 3785^T), respectively.