Biomaterial Database

Membrane transport of p-nitrophenyl-alpha-galactoside by the melibiose carrier of Escherichia coli. 1980

K Ottina, and J Lopilato, and T H Wilson

p-Nitrophenyl-alpha-galactoside (alpha-pNPG) was found to be a substrate for the melibiose transport system of Escherichia coli. This sugar enters induced cells via the carrier and is split by alpha-galactosidase to galactose and p-nitrophenol. In mutant cells lacking the alpha-galactosidase [3H]-alpha-pNPG accumulated to concentrations 15 times higher than the external medium. The transport of alpha-pNPG is inhibited by both Na+ and Li+. Na+ (10 mM) reduced the Km for alpha-pNPG from 0.45 to 0.18 mM and reduced the Vmax from 6.7 nmoles/min/mg dry wt to a value of 3.0.

UI	MeSH Term	Description	Entries
D007700	Kinetics	The rate dynamics in chemical or physical systems.
D008094	Lithium	An element in the alkali metals family. It has the atomic symbol Li, atomic number 3, and atomic weight [6.938; 6.997]. Salts of lithium are used in treating BIPOLAR DISORDER.	Lithium-7,Lithium 7
D008553	Melibiose	A disaccharide consisting of one galactose and one glucose moiety in an alpha (1-6) glycosidic linkage.
D009154	Mutation	Any detectable and heritable change in the genetic material that causes a change in the GENOTYPE and which is transmitted to daughter cells and to succeeding generations.	Mutations
D009598	Nitrophenylgalactosides	Includes ortho-, meta-, and para-nitrophenylgalactosides.	Nitrophenylgalactopyranosides
D004187	Disaccharides	Oligosaccharides containing two monosaccharide units linked by a glycosidic bond.	Disaccharide
D004926	Escherichia coli	A species of gram-negative, facultatively anaerobic, rod-shaped bacteria (GRAM-NEGATIVE FACULTATIVELY ANAEROBIC RODS) commonly found in the lower part of the intestine of warm-blooded animals. It is usually nonpathogenic, but some strains are known to produce DIARRHEA and pyogenic infections. Pathogenic strains (virotypes) are classified by their specific pathogenic mechanisms such as toxins (ENTEROTOXIGENIC ESCHERICHIA COLI), etc.	Alkalescens-Dispar Group,Bacillus coli,Bacterium coli,Bacterium coli commune,Diffusely Adherent Escherichia coli,E coli,EAggEC,Enteroaggregative Escherichia coli,Enterococcus coli,Diffusely Adherent E. coli,Enteroaggregative E. coli,Enteroinvasive E. coli,Enteroinvasive Escherichia coli
D006027	Glycosides	Any compound that contains a constituent sugar, in which the hydroxyl group attached to the first carbon is substituted by an alcoholic, phenolic, or other group. They are named specifically for the sugar contained, such as glucoside (glucose), pentoside (pentose), fructoside (fructose), etc. Upon hydrolysis, a sugar and nonsugar component (aglycone) are formed. (From Dorland, 28th ed; From Miall's Dictionary of Chemistry, 5th ed)	Glycoside
D001693	Biological Transport, Active	The movement of materials across cell membranes and epithelial layers against an electrochemical gradient, requiring the expenditure of metabolic energy.	Active Transport,Uphill Transport,Active Biological Transport,Biologic Transport, Active,Transport, Active Biological,Active Biologic Transport,Transport, Active,Transport, Active Biologic,Transport, Uphill
D012964	Sodium	A member of the alkali group of metals. It has the atomic symbol Na, atomic number 11, and atomic weight 23.	Sodium Ion Level,Sodium-23,Ion Level, Sodium,Level, Sodium Ion,Sodium 23