title: The ineffectiveness of analogs of D-galactal as competitive inhibitors of, and substrates for, beta-D-galactosidase from Escherichia coli.
abstract: 2,6-Anhydro-3-deoxy-aldehydo-D-lyxo-hept-2-enose (7) and 2,6-anhydro-3-deoxy-D-lyxo-hept-2-enitol (8) were synthesized as half-chair analogs of D-galactal (1). As 1 is a strong inhibitor of, as well as a substrate for, beta-D-galactosidase from Escherichia coli, the same properties were expected for 7 and 8; however, both were ineffective. This result, together with those of other authors, allows speculative conclusions on the tight binding of 1 to the enzyme only, when water or an alcohol is bound as a co-substrate.
mesh_terms: D004926:Escherichia coli / Q000201:enzymology*; D005690:Galactose / Q000031:analogs & derivatives* / Q000138:chemical synthesis / Q000494:pharmacology; D005696:Galactosidases / Q000037:antagonists & inhibitors*; D013402:Sugar Alcohols / Q000138:chemical synthesis / Q000494:pharmacology*; D001616:beta-Galactosidase / Q000037:antagonists & inhibitors*
chemical_list: D013402:Sugar Alcohols; C002038:galactal; D005696:Galactosidases; D001616:beta-Galactosidase; D005690:Galactose