Biomaterial Database

Control of phosphoenolpyruvate-dependent phosphotransferase-mediated sugar transport in Escherichia coli by energization of the cell membrane. 1979

E Reider, and E F Wagner, and M Schweiger

The phosphoenolpyruvate-dependent phosphotransferase-mediated sugar transport in Escherichia coli is inhibited by the energized of the membrane. This was shown in intact cells as well as in membrane vesicles. Relaxation of the proton gradient by uncouplers stimulated the uptake of sugars via the phosphotransferase system in aerobically cultured cells. No such effect was seen in anaerobic cells, apparently because the cell membrane of these cells is poorly energized. Energization by respiration of D-lactate or ascorbate inhibited the phosphotransferase uptake system in membrane vesicles. This inhibition was reversed by the addition of cyanide. Oxamate, a specific inhibitor of lactate dehydrogenase, prevented the inhibitory effect of D-lactate. Membrane vesicles prepared from a cytochrome-less mutant were not energized by D-lactate oxidation and the phosphotransferase uptake system was not inhibited.

UI	MeSH Term	Description	Entries
D007773	Lactates	Salts or esters of LACTIC ACID containing the general formula CH3CHOHCOOR.
D008757	Methylglucosides		Methylglucopyranosides
D008759	Methylglycosides
D010728	Phosphoenolpyruvate	A monocarboxylic acid anion derived from selective deprotonation of the carboxy group of phosphoenolpyruvic acid. It is a metabolic intermediate in GLYCOLYSIS; GLUCONEOGENESIS; and other pathways.
D010770	Phosphotransferases	A rather large group of enzymes comprising not only those transferring phosphate but also diphosphate, nucleotidyl residues, and others. These have also been subdivided according to the acceptor group. (From Enzyme Nomenclature, 1992) EC 2.7.	Kinases,Phosphotransferase,Phosphotransferases, ATP,Transphosphorylase,Transphosphorylases,Kinase,ATP Phosphotransferases
D011392	Proline	A non-essential amino acid that is synthesized from GLUTAMIC ACID. It is an essential component of COLLAGEN and is important for proper functioning of joints and tendons.	L-Proline,L Proline
D002462	Cell Membrane	The lipid- and protein-containing, selectively permeable membrane that surrounds the cytoplasm in prokaryotic and eukaryotic cells.	Plasma Membrane,Cytoplasmic Membrane,Cell Membranes,Cytoplasmic Membranes,Membrane, Cell,Membrane, Cytoplasmic,Membrane, Plasma,Membranes, Cell,Membranes, Cytoplasmic,Membranes, Plasma,Plasma Membranes
D003486	Cyanides	Inorganic salts of HYDROGEN CYANIDE containing the -CN radical. The concept also includes isocyanides. It is distinguished from NITRILES, which denotes organic compounds containing the -CN radical.	Cyanide,Isocyanide,Isocyanides
D003580	Cytochromes	Hemeproteins whose characteristic mode of action involves transfer of reducing equivalents which are associated with a reversible change in oxidation state of the prosthetic group. Formally, this redox change involves a single-electron, reversible equilibrium between the Fe(II) and Fe(III) states of the central iron atom (From Enzyme Nomenclature, 1992, p539). The various cytochrome subclasses are organized by the type of HEME and by the wavelength range of their reduced alpha-absorption bands.	Cytochrome
D004579	Electron Transport	The process by which ELECTRONS are transported from a reduced substrate to molecular OXYGEN. (From Bennington, Saunders Dictionary and Encyclopedia of Laboratory Medicine and Technology, 1984, p270)	Respiratory Chain,Chain, Respiratory,Chains, Respiratory,Respiratory Chains,Transport, Electron