sentence: There were no orthologs of genes and predicted proteins in the virulence-associated plasmids pYV , pMT1 , and pPla , and the HPI of Y. pestis in the genomes of the type strains - eight non - or low-pathogenic Yersinia speciesApart from functions encoded on the aforementioned plasmids , HPI and YAPI regions , only nine proteins detected as common to all three Yersinia pathogen species ( Y. pestis , Y. enterocolitica and Y. pseudotuberculosis ) were not found on at least one of the other eight species .