Biomaterial Database

Kinetic studies on NADPH-linked aldehyde reductase from human liver. 1980

B Wermuth, and J P von Wartburg

The mechanism of D-glucuronate reduction by human liver NADPH-dependent aldehyde reductase was investigated. At pH 7.4 the Km values for NADPH, NADP+, D-glucuronate and L-gulonate were 2.2 microM, 6 microM, 3.2 mM and 6 mM, respectively. Product inhibition studies in the forward direction (reduction of glucuronate) gave a competitive pattern for the inhibition of NADPH oxidation by NADP+ and non-competitive patterns for the other three inhibitions. In the backward direction all patterns appeared to be competitive. Deuterium isotope effects were dependent on the concentration of D-glucuronate and decreased to unity at infinite concentrations of D-glucuronate. Our findings suggest for aldehyde reductase a kinetic mechanism with sequential ordered binding of NADPH and D-glucuronate and random dissociation of NADP+ and L-gulonate.

UI	MeSH Term	Description	Entries
D007700	Kinetics	The rate dynamics in chemical or physical systems.
D008099	Liver	A large lobed glandular organ in the abdomen of vertebrates that is responsible for detoxification, metabolism, synthesis and storage of various substances.	Livers
D009249	NADP	Nicotinamide adenine dinucleotide phosphate. A coenzyme composed of ribosylnicotinamide 5'-phosphate (NMN) coupled by pyrophosphate linkage to the 5'-phosphate adenosine 2',5'-bisphosphate. It serves as an electron carrier in a number of reactions, being alternately oxidized (NADP+) and reduced (NADPH). (Dorland, 27th ed)	Coenzyme II,Nicotinamide-Adenine Dinucleotide Phosphate,Triphosphopyridine Nucleotide,NADPH,Dinucleotide Phosphate, Nicotinamide-Adenine,Nicotinamide Adenine Dinucleotide Phosphate,Nucleotide, Triphosphopyridine,Phosphate, Nicotinamide-Adenine Dinucleotide
D005965	Glucuronates	Derivatives of GLUCURONIC ACID. Included under this heading are a broad variety of acid forms, salts, esters, and amides that include the 6-carboxy glucose structure.	Glucosiduronates,Glucuronic Acids,Acids, Glucuronic
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D000445	Aldehyde Oxidoreductases	Oxidoreductases that are specific for ALDEHYDES.	Aldehyde Oxidoreductase,Oxidoreductase, Aldehyde,Oxidoreductases, Aldehyde
D066298	In Vitro Techniques	Methods to study reactions or processes taking place in an artificial environment outside the living organism.	In Vitro Test,In Vitro Testing,In Vitro Tests,In Vitro as Topic,In Vitro,In Vitro Technique,In Vitro Testings,Technique, In Vitro,Techniques, In Vitro,Test, In Vitro,Testing, In Vitro,Testings, In Vitro,Tests, In Vitro,Vitro Testing, In