Inducible N-acetyglucosamine-binding protein in yeasts.

Addition of N-acetylglucosamine (GlcNAc) to the medium elicits an immediate synthesis of a specific GlcNAc-binding protein in yeasts. Synthesis of this protein requires the continuous presence of GlcNAc as the inducer and is inhibited completely by the inhibitors of ribonucleic acid and protein syntheses. Furthermore, this protein has been partially purified from GlcNAc-grown Candida albicans cells and is quite distinct from the other induced enzymes of the GlcNAc catabolic pathway. A good correlation between the level of GlcNAc-binding protein and GlcNAc uptake capacity of the cells during induction was observed. Some of the sugars, e.g., N-acetylmannosamine, N-acetylgalactosamine, and glucose, had a similar competitive effect on the binding of GlcNAc as well as on its uptake. Furthermore, both the binding and uptake activities were sensitive to sulfhydryl reagents.