Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0038362 (stomatitis)
 8,852 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Interaction with excess unilamellar phosphatidylcholine (PC) vesicles resulted in depletion of as much as 90% of the cholesterol from the membrane of intact vesicular stomatitis (VS) virus. The cholesterol depletion was not significantly influenced by the proteolytic removal of virion glycoprotein spikes, but it was temperature dependent. Cholesterol depletion caused substantial reduction in anisotropy of the VS virion membrane as measured by fluorescence depolarization of the lipophilic probe 1,6-diphenyl-1,3,5-hexatriene; residual adsorbed vesicles represent a significant factor in this apparent increase in virion membrane fluidity. Interaction with PC vesicles resulted in a substantial loss of VS viral infectivity as measured by plating efficiency on L-cell monolayers. Reduction in infectivity appeared to be related to temperature-dependent depletion of virion cholesterol by PC vesicles. Interaction of VS virions with cholesterol-containing PC vesicles resulted in significantly less decline in infectivity, but attempts to restore cholesterol and infectivity to depleted VS virions were unsuccessful. Depletion of virion cholesterol apparently results through collision with PC vesicles rather than movement of cholesterol monomers or micelles through the aqueous phase, because PC vesicle-virion interaction in the presence of cholesterol oxidase did not result in substantial oxidation of translocated cholesterol.
 ...
PMID:Interaction of vesicular stomatitis virus with lipid vesicles: depletion of cholesterol and effect on virion membrane fluidity and infectivity. 21 Dec 63

Cholesterol present in intact brush-border membrane vesicles made from rabbit small intestine is a poor substrate for cholesterol oxidase (EC 1.1.3.6, from Nocardia sp. and Nocardia erythropolis). It becomes susceptible to oxidation by the enzyme only after the addition of detergent, e.g., Triton X-100, in quantities sufficient to disrupt the membrane. This is also true for cholesterol present in bilayers of small unilamellar phosphatidylcholine or phosphatidylserine vesicles made by ultrasonication. The data presented here on intestinal brush-border membrane are in good agreement with results reported on other biological membranes, e.g., from erythrocytes and vesicular stomatitis virus, but are somewhat different from those on rat intestinal brush-border membrane. Our results on phospholipid bilayers agree well with published work on model membranes. From the work presented we conclude that, with our present understanding, cholesterol oxidase can hardly be used to probe the distribution of cholesterol in biological membranes. A prerequisite for using the enzyme successfully as such a probe would be the understanding of the factors controlling the interaction of the enzyme with its substrate cholesterol. The question under which conditions cholesterol oxidase could be useful for probing the distribution and preferred location of cholesterol in biological membranes is discussed.
 ...
PMID:Cholesterol oxidase as a structural probe of biological membranes: its application to brush-border membrane. 345

Several new bacterial host-vector systems for Klebsiella, Erwinia, Xanthomonas, Nocardia, and Streptomyces have been developed. With these host-vector systems, a strain of Klebsiella, which overproduces the extracellular starch-debranching enzyme, pullulanase, has been developed. The gene for cholesterol oxidase was cloned and used to develop a strain of Streptomyces lividans that extracellularly produces the enzyme, cholesterol oxidase, which is utilized to process cholesterol and diagnostically. The genes for these two enzymes were sequenced, and several interesting facts about their structures and secretory mechanisms were found. For expression of mammalian gene products, the expression vectors. pYM001 to pYM008, containing the lambda P(R)P(L) promoter, which is controlled by a thermolabile repressor, have been developed. The activities of these promoters were compared in various bacterial strains with the galK monitoring system. E. coli promoters, such as lac, trp, tac, lambda P(R), P(L), and P(R)P(L), were found to be expressed in other enteric bacteria and in Bacillus subtilis. With these expression vectors, the vesicular stomatitis virus-nucleocapsid, monkey metallothionein, and human apolipoprotein A1 genes were expressed in E. coli.
 ...
PMID:Genetic designs for product formation in recombinant microbes. 1454 2