Biomaterial Database

Studies on the regulation of enolases and compartmentation of cytosolic enzymes in Saccharomyces cerevisiae. 1987

K D Entian, and B Meurer, and H Köhler, and K H Mann, and D Mecke

Three enolase isoenzymes can be distinguished after electrophoresis of yeast crude extracts. After adding glucose to derepressed cells, there was a coordinated increase in the activity of enolase I and decrease in enolase II activity. Enolase I was found to be repressed and enolase II simultaneously induced by glucose. The third enolase activity remained unchanged and was identified as that of a hybrid enzyme. Enolase catalyses the first common step of glycolysis and gluconeogenesis. Gluconeogenic enolase I shows substrate inhibition for 2-phosphoglycerate (glycolytic substrate) and glycolytic enolase II is substrate-inhibited by phosphoenolpyruvate (gluconeogenic substrate). The gluconeogenic reaction was inhibited up to 45% by physiological concentrations of fructose 1,6-bisphosphate. To test for cytological compartmentation, a method was developed for isolating microsomes. Effective enrichment of rough and smooth endoplasmic reticulum was demonstrated by electron microscopy. No evidence was obtained for any compartmentation of either enolases or other glycolytic enzymes.

UI	MeSH Term	Description	Entries
D007700	Kinetics	The rate dynamics in chemical or physical systems.
D008854	Microscopy, Electron	Microscopy using an electron beam, instead of light, to visualize the sample, thereby allowing much greater magnification. The interactions of ELECTRONS with specimens are used to provide information about the fine structure of that specimen. In TRANSMISSION ELECTRON MICROSCOPY the reactions of the electrons that are transmitted through the specimen are imaged. In SCANNING ELECTRON MICROSCOPY an electron beam falls at a non-normal angle on the specimen and the image is derived from the reactions occurring above the plane of the specimen.	Electron Microscopy
D010751	Phosphopyruvate Hydratase	A hydro-lyase that catalyzes the dehydration of 2-phosphoglycerate to form PHOSPHOENOLPYRUVATE. Several different isoforms of this enzyme exist, each with its own tissue specificity.	Enolase,Neuron-Specific Enolase,2-Phospho-D-Glycerate Hydro-Lyase,2-Phospho-D-Glycerate Hydrolase,2-Phosphoglycerate Dehydratase,Enolase 2,Enolase 3,Muscle-Specific Enolase,Nervous System-Specific Enolase,Non-Neuronal Enolase,alpha-Enolase,beta-Enolase,gamma-Enolase,2 Phospho D Glycerate Hydro Lyase,2 Phospho D Glycerate Hydrolase,2 Phosphoglycerate Dehydratase,Dehydratase, 2-Phosphoglycerate,Enolase, Muscle-Specific,Enolase, Nervous System-Specific,Enolase, Neuron-Specific,Enolase, Non-Neuronal,Hydratase, Phosphopyruvate,Hydro-Lyase, 2-Phospho-D-Glycerate,Muscle Specific Enolase,Nervous System Specific Enolase,Neuron Specific Enolase,Non Neuronal Enolase,System-Specific Enolase, Nervous,alpha Enolase,beta Enolase,gamma Enolase
D002244	Carbon	A nonmetallic element with atomic symbol C, atomic number 6, and atomic weight [12.0096; 12.0116]. It may occur as several different allotropes including DIAMOND; CHARCOAL; and GRAPHITE; and as SOOT from incompletely burned fuel.	Carbon-12,Vitreous Carbon,Carbon 12,Carbon, Vitreous
D002384	Catalysis	The facilitation of a chemical reaction by material (catalyst) that is not consumed by the reaction.	Catalyses
D002451	Cell Compartmentation	A partitioning within cells due to the selectively permeable membranes which enclose each of the separate parts, e.g., mitochondria, lysosomes, etc.	Cell Compartmentations,Compartmentation, Cell,Compartmentations, Cell
D003600	Cytosol	Intracellular fluid from the cytoplasm after removal of ORGANELLES and other insoluble cytoplasmic components.	Cytosols
D004589	Electrophoresis, Disc	Electrophoresis in which discontinuities in both the voltage and pH gradients are introduced by using buffers of different composition and pH in the different parts of the gel column. The term 'disc' was originally used as an abbreviation for 'discontinuous' referring to the buffers employed, and does not have anything to do with the shape of the separated zones.	Electrophoresis, Disk,Disc Electrophoresis,Disk Electrophoresis
D004721	Endoplasmic Reticulum	A system of cisternae in the CYTOPLASM of many cells. In places the endoplasmic reticulum is continuous with the plasma membrane (CELL MEMBRANE) or outer membrane of the nuclear envelope. If the outer surfaces of the endoplasmic reticulum membranes are coated with ribosomes, the endoplasmic reticulum is said to be rough-surfaced (ENDOPLASMIC RETICULUM, ROUGH); otherwise it is said to be smooth-surfaced (ENDOPLASMIC RETICULUM, SMOOTH). (King & Stansfield, A Dictionary of Genetics, 4th ed)	Ergastoplasm,Reticulum, Endoplasmic
D005943	Gluconeogenesis	Biosynthesis of GLUCOSE from nonhexose or non-carbohydrate precursors, such as LACTATE; PYRUVATE; ALANINE; and GLYCEROL.