Linked Life Data

10467734

Source:http://linkedlifedata.com/resource/pubmed/id/10467734

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
7
pubmed:dateCreated
1999-10-4
pubmed:abstractText
In rat adrenal gland and gastric mucosa putrescine is efficiently oxidized to GABA via gamma-aminobutyraldehyde (ABAL) by action of diamine oxidase and aldehyde dehydrogenase. Having turned our attention on the rat intestinal mucosa, where putrescine uptake and diamine oxidase are active, we have purified and characterized an aldehyde dehydrogenase optimally active on gamma-aminobutyraldehyde. A dimer with a subunit molecular weight of 52,000, the native enzyme binds ABAL and NAD+ with high affinity: at pH 7.4, Km values are equal to 18 and 14 microM, respectively. Affinity for betaine aldehyde is much lower (Km = 285 microM), but the efficiency is equally good, thanks to a high value of V. Unaffected by disulfiram and Mg2+, the enzyme is activated by high NAD+ concentrations (Vnn = 1.6 x Vn) and is competitively inhibited by NADH. According to the best fitting model, the dimeric enzyme only binds one NADH and the mixed complex enzyme-NAD(+)-NADH is inactive. The increase of activity promoted by NAD+ can therefore be ascribed to an allosteric effect, rather than to the activation of a second reaction center. Highly stable at pH 6.8 in the presence of dithiothreitol and high phosphate concentrations, ABALDH is inactivated by ion-exchange resins and by cationic buffers. Our results show that the enzyme can be effectively involved in the metabolism of biogenic amines and, with a K(m) for ABAL lower than 20 microM, in the synthesis of GABA.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jul
pubmed:issn
1357-2725
pubmed:author
pubmed:issnType
Print
pubmed:volume
31
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
777-86
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed-meshheading:10467734-Aldehyde Dehydrogenase, pubmed-meshheading:10467734-Aldehydes, pubmed-meshheading:10467734-Animals, pubmed-meshheading:10467734-Dimerization, pubmed-meshheading:10467734-Disulfiram, pubmed-meshheading:10467734-Enzyme Inhibitors, pubmed-meshheading:10467734-Enzyme Stability, pubmed-meshheading:10467734-Hydrogen-Ion Concentration, pubmed-meshheading:10467734-Intestinal Mucosa, pubmed-meshheading:10467734-Isoelectric Point, pubmed-meshheading:10467734-Isoenzymes, pubmed-meshheading:10467734-Kinetics, pubmed-meshheading:10467734-Magnesium, pubmed-meshheading:10467734-Male, pubmed-meshheading:10467734-Molecular Weight, pubmed-meshheading:10467734-NAD, pubmed-meshheading:10467734-Rats, pubmed-meshheading:10467734-Rats, Wistar, pubmed-meshheading:10467734-Substrate Specificity
pubmed:year
1999
pubmed:articleTitle
Aldehyde dehydrogenase from rat intestinal mucosa: purification and characterization of an isozyme with high affinity for gamma-aminobutyraldehyde.
pubmed:affiliation
Dipartimento di Medicina e Oncologia Sperimentale, Università di Torino, Turin, Italy.
pubmed:publicationType
Journal Article, In Vitro, Research Support, Non-U.S. Gov't