Note: cyclohexenoesculetin-beta-D-glucoside: a new substrate for the detection of bacterial beta-D-glucosidase.
A new substrate for the detection of bacterial beta-D-glucosidase was evaluated as an alternative to aesculin. This substrate, 3,4-cyclohexenoesculetin-7-beta-D-glucoside, was compared with aesculin for the detection of beta-D-glucosidase in 150 enterococci, 40 streptococci, 12 Listeria sp. and 250 strains of Enterobacteriaceae. In the Gram-positive strains tested, aesculin hydrolysis correlated with hydrolysis of 3,4-cyclohexenoesculetin-7-beta-D-glucoside. In the Gram-negative strains the new substrate was hydrolysed by all aesculin-positive strains and also by four strains (10%) of Escherichia coli which gave a negative aesculin reaction. 3,4-Cyclohexenoesculetin-7-beta-D-glucoside was shown to be a reliable alternative to aesculin and was shown to have significant advantages over aesculin when incorporated into solid media. This was due to the non-diffusible end product produced by hydrolysis of 3,4-cyclohexenoesculetin-7-beta-D-glucoside in the presence of iron.
James
A L
AL
Department of Chemical and Life Sciences, University of Northumbria, Newcastle-upon-Tyne, UK.
Perry
J D
JD
Ford
M
M
Armstrong
L
L
Gould
F K
FK
D001419:Bacteria / Q000145:classification* / Q000201:enzymology; D015373:Bacterial Typing Techniques; D002863:Chromogenic Compounds / Q000138:chemical synthesis; D004755:Enterobacteriaceae / Q000145:classification / Q000201:enzymology; D004929:Esculin; D005697:Galactosides / Q000138:chemical synthesis; D006094:Gram-Positive Bacteria / Q000145:classification / Q000201:enzymology; D014468:Umbelliferones / Q000138:chemical synthesis; D001617:beta-Glucosidase / Q000032:analysis*
D002863:Chromogenic Compounds; D005697:Galactosides; D014468:Umbelliferones; C101993:cyclohexenoesculetin-beta-galactoside; D004929:Esculin; D001617:beta-Glucosidase