Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
6
pubmed:dateCreated
1983-5-5
pubmed:abstractText
The demonstration of the ornithine biosynthesis from glutamate in cell-free homogenates of rat intestinal mucosa by Ross, G., Dunn, D., and Jones, M.E. (1978) Biochem. Biophys. Res. Commun. 85, 140-147 suggested that this tissue might have the capacity to convert glutamate to pyrroline-5-carboxylate (P5C). We have shown in the preceding paper (Wakabayashi, Y., and Jones, M.E. (1983) J. Biol. Chem. 258, 3865-3872) that this is the case. The intracellular distribution of the P5C-synthesizing activity was investigated utilizing a newly developed procedure for subcellular fractionation of the rat intestinal mucosa. We found that the activity resided in the mitochondrial fraction as characterized by marker enzymes and an electron micrograph. The mitochondrial membrane fraction, freed of the soluble matrix and intermembrane space enzymes, retained all of the P5C-synthesizing activity. Addition of the soluble fraction to the membrane fraction did not affect the activity. P5C synthase, the name we have chosen for the protein(s) that catalyzes P5C synthesis from glutamate when ATP and NADPH are present, is susceptible to thermal inactivation in the presence of detergent. By lowering the incubation temperature to or below 20 degrees C, one can obtain a linear production of P5C with respect to time and protein concentration. Lower incubation temperatures are recommended for routine assay of this enzyme(s). Addition of 30% glycerol to the incubation mixture resulted in a linear formation of P5C with time at 30 degrees C; this and other data suggest that polyhydroxylic compounds may protect this protein against denaturation. Preliminary experiments suggest that P5C synthase can be extracted from a mitochondrial membrane in the presence of detergent, a high salt concentration, and glycerol. The possibility that the enzyme(s) is located in the inner mitochondrial membrane is discussed.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Mar
pubmed:issn
0021-9258
pubmed:author
pubmed:issnType
Print
pubmed:day
25
pubmed:volume
258
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
3873-82
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1983
pubmed:articleTitle
Pyrroline-5-carboxylate synthesis from glutamate by rat intestinal mucosa. Subcellular localization and temperature stability.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S.