Do Human-Infecting Yersinia enterocolitica Isolates Exhibit Adaptive Phenotypes?

Area of Science:

• Microbiology
• Food Safety
• Genomics

Background:

• Yersinia enterocolitica biotype 4 (BT4) and biotype 2 (BT2) are significant in human yersiniosis.
• Understanding the phenotypic differences between animal and human-associated Y. enterocolitica isolates is crucial for public health.

Purpose of the Study:

• To investigate phenotypic variations in Yersinia enterocolitica isolates based on their genetic clustering with human isolates.
• To assess survival, motility, adherence, biocide resistance, and Caco-2 cell infection capabilities.

Main Methods:

• Core genome multi-locus sequence typing (cgMLST) was used to cluster porcine (P) BT4 and bovine (B) BT2 isolates with human (H) isolates.
• Phenotypic tests included survival at 4°C, motility at low temperatures, adherence to stainless steel, biocide resistance, and Caco-2 cell infection.

Main Results:

• No significant phenotypic differences were found between clustered (P+H+, B+H+) and non-clustered (P+H-, B+H-) BT4 porcine and BT2 bovine isolates, except for motility.
• Porcine isolates clustering with human strains showed reduced motility, while bovine isolates clustering with human strains exhibited higher motility.

Conclusions:

• Motility differences in Y. enterocolitica isolates may reflect adaptation to different transmission routes within the food chain.
• Animal isolates not clustering with human strains possess traits facilitating food chain transmission, suggesting potential for human exposure.