Disease relevance of U 6658

• Studies on bacterial cell wall inhibitors. X. Properties of phosph-N-acetylmuramoyl-pentapeptide-transferase in peptidoglycan synthesis of Bacillus megaterium and its inhibition by amphomycin [1].
• This step of peptidoglycan biosynthesis is also the target for the bacteriolytic E protein from bacteriophage phiX174, and for cyclic peptides of the amphomycin family which complex the undecaprenyl phosphate co-substrate [2].
• Amphomycin though withdrawn as an antibiotic against the gram-positive bacterial infection, can certainly serve as an excellent tool for determination of the topology of Dol-P in the endoplasmic reticulum membranes which has been otherwise impossible [3].

High impact information on U 6658

• The transferase activity has an optimal pH of 7.5- 8.5, requires Mn2+, is unaffected by tunicamycin or amphomycin, and is strongly inhibited by UDP [4].
• The inhibitory effect of the lipopeptide antibiotic amphomycin on the mechanism of mannosylphosphoryldolichol biosynthesis by calf brain rough endoplasmic reticulum membranes has been studied extensively [5].
• These data demonstrated that amphomycin interacted with the active site of the glycosyl-carrier lipid (Dol-P), thereby preventing its participation at the enzymatic reaction [5].
• On the other hand, when mannosylphosphoryldolichol synthase activity was measured in the presence of amphomycin and as a function of dolichylmonophosphate (Dol-P) concentrations, the shape of the substrate velocity curve changed from a rectangular hyperbola to a sigmoid [5].
• Inhibition of glycosylation by amphomycin and sugar nucleotide analogs PP36 and PP55 indicates that Haloferax volcanii beta-glucosylates both glycoproteins and glycolipids through lipid-linked sugar intermediates: evidence for three novel glycoproteins and a novel sulfated dihexosyl-archaeol glycolipid [6].

Biological context of U 6658

• Amphomycin: effect of the lipopeptide antibiotic on the glycosylation and extraction of dolichyl monophosphate in calf brain membranes [7].

Anatomical context of U 6658

• Furthermore, exposure of capillary endothelial cells to amphomycin, followed by the monoclonal antibody to amphomycin, followed sequentially by staining with FITC-conjugated goat anti-mouse IgG and examination under a fluorescent microscope gives intense fluorescence at the perinuclear region of the cell with a structure reminiscent of the ER [8].
• Amphomycin at very high concentration (500 micrograms mL-1) was toxic to embryos but at concentrations up to 250 micrograms mL-1 had no effect on compaction and development of blastocysts [9].

Associations of U 6658 with other chemical compounds

• In vivo and in vitro inhibition of lipid-linked saccharide and glycoprotein synthesis in plants by amphomycin [10].
• In addition. the antibiotic amphomycin selectively inhibited the formation of mannosylated products suggesting polyprenolmonophosphate-mannose (C15 50-P-Man) was the immediate mannose donor in all mannosylation reactions observed [11].

Gene context of U 6658

• Preincubation of amphomycin with the antibody partially reduced the inhibitory action of amphomycin on dolichol phosphate mannosyltransferase (EC 2.4.1.83) [8].

Analytical, diagnostic and therapeutic context of U 6658

• The antibody belongs to the IgG+IgM subclasses and is specific for amphomycin when analyzed by the enzyme-linked immunoassay and immunoblot procedures [8].

References