title: Simple assay of calcium dependency for virulent plasmid-bearing clones of Yersinia enterocolitica.
abstract: A simplified procedure to detect the calcium dependency of virulent plasmid-bearing strains of Yersinia enterocolitica was developed. A low-calcium, agarose-based medium of brain heat infusion with added magnesium effectively differentiated plasmid-bearing and plasmidless isolates. Further, the expression of calcium dependency in plasmid-bearing strains of Y. enterocolitica as measured by the average colony diameter was proportional to the calcium concentration of the assay.
authors.affiliation: Eastern Regional Research Center, U.S. Department of Agriculture, Philadelphia, Pennsylvania 19118.
authors.forename: S
authors.initials: S
authors.lastname: Bhaduri
authors.forename: C
authors.initials: C
authors.lastname: Turner-Jones
authors.forename: M M
authors.initials: MM
authors.lastname: Taylor
authors.forename: R V
authors.initials: RV
authors.lastname: Lachica
mesh_terms: D002118:Calcium / Q000494:pharmacology*; D003470:Culture Media; D010957:Plasmids; D014774:Virulence; D015008:Yersinia enterocolitica / Q000235:genetics / Q000378:metabolism* / Q000472:pathogenicity
chemical_list: D003470:Culture Media; D002118:Calcium