[gamma Glutamyltransferase activity in the genus "Yersinia" (author's transl)].

The expression of gamma-glutamyltransferase activity was studied among 87 strains representing all the Yersinia species. Y. pestis lacked constantly this enzyme, while y. pseudotuberculosis expressed it as a rule. This test, when positive, is useful for the exclusion of a suspected Y. pestis diagnosis. All the other Yersinia species, like most of the Enterobacteriaceae, showed a gamma-glutamyltransferase activity.