Arcobacter cloacae sp. nov. and Arcobacter suis sp. nov., two new species isolated from food and sewage.

Three strains recovered from mussels (F26), sewage (SW28-13(T)) and pork meat (F41(T)) were characterized as Arcobacter. They did not appear to resemble any known species on the basis of their 16S rDNA-RFLP patterns and the rpoB gene analyses. However, strains F26 and SW28-13(T) appeared to be the same species. The 16S rRNA gene sequence similarity of strains SW28-13(T) and F41(T) to the type strains of all other Arcobacter species ranged from 94.1% to 99.6% and 93.4% to 98.8%, respectively. Phenotypic characteristics and the DNA-DNA hybridization (DDH) results showed that they belonged to 2 new Arcobacter species. A multilocus phylogenetic analysis (MLPA) with the concatenated sequences of 5 housekeeping genes (gyrA, atpA, rpoB, gyrB and hsp60) was used for the first time in the genus, showing concordance with the 16S rRNA gene phylogenetic analysis and DDH results. The MALDI-TOF mass spectra also discriminated these strains as two new species. The names proposed for them are Arcobacter cloacae with the type strain SW28-13(T) (=CECT 7834(T)=LMG 26153(T)) and Arcobacter suis with the type strain F41(T) (=CECT 7833(T)=LMG 26152(T)).