Microbiology, University of Alberta, Edmonton, Alberta T6G 2E9, Canada polyhydroxyalkanoate (PHA) in mutant Azotobacter vinelandii UWD, the kinetic properties of 3-ketothiolase, acetoacetyl-CoA reductase, and /3hydroxybutyrate dehydrogenase were examined. The regulatiorn of the condensation of acetyl-CoA mediated by 3-ketothiolase was narmal, in that it was negatively regulated by free CoA, but...

Sir: In the foregoing communications' we reported the synthesis of 4'-deoxymycaminosyl tylonolide (1a) which showed fairly strong antibacterial activity. This paper describes the syntheses of derivatives of la and of mycaminosyl tylonolide (Ib) modified at C-23. Treatment of the diethylacetal (2a) of la with acetic anhydride in acetonitrile as described previously" gave the 2'-O-acetyl derivati...

The main interaction between pyridine and zeolites leads to form a hydrogen bond between the N atom of pyridine and OH groups of zeolites. The present work reports a theoretical study about the structural, vibrational and topological properties of the charge distribution of the molecular complexes between pyridine and a series of acids sites of zeolites. The calculated structural parameters...

lead is a common toxic agent which impairs various organs functions of the body. the basis of this toxicity is believed to be the negative influence on enzymatic system of cells. in the past few years, increasing consideration has been given to interactions occurring between lead and some essential metals including se and zn. based on the finding that some trace elements could reverse the toxic...