Effect of bacitracin on the biosynthesis of dolichol derivatives in calf pancreas microsomes.

Abstract

Publisher Summary bacitracin is a cyclic peptide antibiotic that forms a complex with polyisoprenyl pyrophosphates in the presence of a divalent cation. In bacteria, the formation of this complex prevents the regeneration of undecaprenyl phosphate, which is essential for the biosynthesis of peptidoglycan in the cell wall. This chapter discusses an experiment in which the effect of bacitracin on the some enzymic reactions was investigated. In the experiment, the calf pancreas microsomes were incubated with labeled nucleotide sugars. The radioactivity incorporated into glycolipids extracted with chloroform–methanol (2:1) (CM extract) and chloroform–methanol–water (10:10:2.5) (CMW extract) and into the precipitate (Ppt) containing glycoproteins was measured. It was found from the experiment that bacitracin inhibited the formation of Dol-PP-GlcNAc and Dol-PP-(GlcNAc) 2 from UDP-N-acetyl-D-[ 14 C]lglucosamine and endogenous dolichyl phosphate and the incorporation of D-[14-4C]mannose into dolichyl pyrophosphate oligosaccharides. It also inhibited the incorporation of N-acetyl-D-[14C] glucosamine and D-[14C] mannose into the precipitate.