Table 1: Biotyping scheme of Y. enterocolitica (adapted from [33, 34]).

TestReaction of biotype
1A1B2345

Lipase (Tween hydrolysis)++
Aesculin hydrolysisV
Indole production++(+)
D-Xylose fermentation++++v
Voges-Proskauer reaction+++++(+)
Trehalose fermentation+++++
Nitrate reduction+++++
Pyrazinamidase+
B-D-Glucosidase+
Proline peptidasev

+, positive; (+), delayed positive; –, negative; v, variable reactions.