I. DEVELOPMENT OF A SYSTEM SUITABLE FOR STUDYING THIS PHENOMENON

J. L. Koppel ¹, C. J. Porter ¹, and Bruce F. Crocker ¹

¹ From the Department of Biochemistry, University of Toronto, Canada

1. An experimental system suitable for the study of enzyme formation has been described.

2. The formation of ß-galastosidase in E. coli B could be induced by lactose, melibiose, D-galactose and ß-methyl-D-galactoside.

3. Lactose-induced ß-galactosidase formation was found to be inhibited by D-glucose, D-mannose, D-fructose, D-arabinose, and raffinose.

4. The utilizable structural analogue, D-glucose, was found to either stimulate or inhibit ß-galactosidase formation depending upon its concentration. D-Arabinose, on the other hand, a non-utilizable structural analogue, is only capable of inhibiting, whereas succinic acid, a structurally unrelated energy source, is only capable of stimulating ß-galactosidase formation.

5. D-Arabinose inhibition of lactose-induced ß-galactosidase formation was found to be of the competitive type.

6. Some of the implications of these findings have been discussed.

CiteULike    Complore    Connotea    Del.icio.us    Digg    Reddit    Technorati    What's this?

Home | Help | Feedback | Subscriptions | Archive | Search | Table of Contents