Biomaterial Database

Long-chain-acyl-CoA synthetase and very-long-chain-acyl-CoA synthetase activities in peroxisomes and microsomes from rat liver. An enzymological study. 1991

W Lageweg, and R J Wanders, and J M Tager

Department of Pediatrics, University of Amsterdam, The Netherlands.

We have investigated the palmitic acid (C16:0) and cerotic acid (C26:0) activating activities in rat-liver microsomes and peroxisomes. The activation of the two fatty acids showed similar dependencies on ATP and coenzyme A, reflected in about equal apparent Km values both in microsomes and peroxisomes. In microsomes and peroxisomes similar apparent Km values for palmitic acid were found (15 microM and 22.8 microM, respectively), whereas apparent Km values for cerotic acid were 8.4 microM and 1.0 microM in microsomes and peroxisomes, respectively. The activation of cerotic acid was found to be inhibited to a progressively greater extent by increasing concentrations of 1-pyrenedecanoic acid (P10) as compared to the activation of palmitic acid, both in microsomes and peroxisomes. The inhibition by P10 of palmitic acid activation and cerotic acid activation was non-competitive in both organelles. From the observation that P10 activation is not affected by palmitic acid and cerotic acid, we conclude that P10 is activated by a distinct enzyme. Furthermore, our results are in accordance with earlier suggestions that activation of cerotic acid is brought about by an enzyme distinct from the palmitoyl-CoA synthetase.

UI	MeSH Term	Description	Entries
D007700	Kinetics	The rate dynamics in chemical or physical systems.
D008297	Male		Males
D008830	Microbodies	Electron-dense cytoplasmic particles bounded by a single membrane, such as PEROXISOMES; GLYOXYSOMES; and glycosomes.	Glycosomes,Glycosome,Microbody
D008862	Microsomes, Liver	Closed vesicles of fragmented endoplasmic reticulum created when liver cells or tissue are disrupted by homogenization. They may be smooth or rough.	Liver Microsomes,Liver Microsome,Microsome, Liver
D010169	Palmitic Acids	A group of 16-carbon fatty acids that contain no double bonds.	Acids, Palmitic
D011919	Rats, Inbred Strains	Genetically identical individuals developed from brother and sister matings which have been carried out for twenty or more generations or by parent x offspring matings carried out with certain restrictions. This also includes animals with a long history of closed colony breeding.	August Rats,Inbred Rat Strains,Inbred Strain of Rat,Inbred Strain of Rats,Inbred Strains of Rats,Rat, Inbred Strain,August Rat,Inbred Rat Strain,Inbred Strain Rat,Inbred Strain Rats,Inbred Strains Rat,Inbred Strains Rats,Rat Inbred Strain,Rat Inbred Strains,Rat Strain, Inbred,Rat Strains, Inbred,Rat, August,Rat, Inbred Strains,Rats Inbred Strain,Rats Inbred Strains,Rats, August,Rats, Inbred Strain,Strain Rat, Inbred,Strain Rats, Inbred,Strain, Inbred Rat,Strains, Inbred Rat
D012097	Repressor Proteins	Proteins which maintain the transcriptional quiescence of specific GENES or OPERONS. Classical repressor proteins are DNA-binding proteins that are normally bound to the OPERATOR REGION of an operon, or the ENHANCER SEQUENCES of a gene until a signal occurs that causes their release.	Repressor Molecules,Transcriptional Silencing Factors,Proteins, Repressor,Silencing Factors, Transcriptional
D003066	Coenzyme A Ligases	Enzymes that catalyze the formation of acyl-CoA derivatives. EC 6.2.1.	Acyl CoA Synthetase,Acyl CoA Synthetases,Acyl Coenzyme A Synthetase,Acyl Coenzyme A Synthetases,Coenzyme A Ligase,Coenzyme A Synthetase,Coenzyme A Synthetases,Acid-Thiol Ligases,Co A Ligases,A Ligase, Coenzyme,A Synthetase, Coenzyme,Acid Thiol Ligases,CoA Synthetase, Acyl,CoA Synthetases, Acyl,Ligase, Coenzyme A,Ligases, Acid-Thiol,Ligases, Co A,Ligases, Coenzyme A,Synthetase, Acyl CoA,Synthetase, Coenzyme A,Synthetases, Acyl CoA,Synthetases, Coenzyme A
D003652	Decanoic Acids	10-carbon saturated monocarboxylic acids.	Capric Acids,Acids, Capric,Acids, Decanoic
D004789	Enzyme Activation	Conversion of an inactive form of an enzyme to one possessing metabolic activity. It includes 1, activation by ions (activators); 2, activation by cofactors (coenzymes); and 3, conversion of an enzyme precursor (proenzyme or zymogen) to an active enzyme.	Activation, Enzyme,Activations, Enzyme,Enzyme Activations