During a project focusing on the diversity of meat microbiota associated with beef ripening, a Pseudomonas strain was isolated exhibiting high 16S rRNA gene sequence similarities (>99 %) to Pseudomonas carnis DSM 107652T, P. lactis DSM 29167T, P. paralactis DSM 29164T and P. azotoformans DSM 18862T. Phylogenetic analysis of the complete rpoB gene sequences of the isolate V5/DAB/2/5T indicated a separate branch with about 99.0 % nucleotide identities to the closest relatives P. carnis DSM 107652T, P. lactis DSM 29167T and P. paralactis DSM 29164T, while average nucleotide identities (ANIb) calculated from the draft genomes were 94.8, 94.2 and 90.2 %, respectively. Pairwise genome-to-genome distance calculations (GGDC) resulted in values of 67.7, 63.5 and 45.7 %, respectively, lying below the actual species demarcation line as well. A second isolate, UBT403, was detected some years later by using matrix-assisted laser desorption ionization-time of flight MS of the microbiota of minced beef. The fatty acid profile of V5/DAB/2/5T consisted of C16 : 0, summed feature C 16 : 1 ω7c/iso-C15 : 0 2-OH, C18 : 1 ω7c, C17 : 0 cyclo, C12 : 0, C12 : 0 3-OH, C10 : 0 3-OH and C12 : 0 2-OH. The major cellular lipids were aminopholipids, phospholipids, phosphatidylethanolamine and phosphatidylglycerol; the major quinone was Q9 with a minor proportion of Q8. Based on phenotypic and chemotaxonomic characterizations, the isolates can be considered as representing a novel species, for which the name Pseudomonas paracarnis sp. nov. is proposed. The type strain is V5/DAB/2/5T (=DSM 111363T=LMG 31846T); a second strain is UBT403 (=DSM 111362=LMG 31847).
Keywords: Pseudomonas; beef; dry ageing; meat; meat ripening.