Linked Life Data

9587028

Source:http://linkedlifedata.com/resource/pubmed/id/9587028

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:dateCreated
1998-7-14
pubmed:abstractText
Deficient activity of an enzyme can result from a defect in the conversion of the vitamin to a co-enzyme as well from an abnormal apo-enzyme or disturbed binding of coenzyme to enzyme. Conversion of dietary vitamin to intracellular active co-enzyme can be complex and require many physiological and biochemical processes including stomach release of bound vitamin, intestinal uptake, carriers/transport, blood transport, cellular uptake, intracellular release and intracellular compartmentalisation. Disorders of malabsorption (food cobalamin malabsorption, intrinsic factor deficiency and abnormal enterocyte cobalamin processing) and transport proteins (transcobalamin II deficiency, R-binder deficiency) mostly lead to disturbed function of the two cobalamin requiring enzymes, methylmalonyl CoA mutase and methionine synthase. Defects of early steps of intracellular cobalamin (cblF, cbl C/D) result in marked deficiencies of both cobalamin co-enzymes and homocystinuria combined with methylmalonic aciduria. Defective synthesis of adenosyl cobalamin in the cbl A/B defects leads to methylmalonyl CoA mutase. Isolated methionine synthase deficiency is also classified as a cobalamin disorder due to its associated deficient formation of methylcobalamin. Folate disorders include methylene-tetrahydrofolate reductase deficiency and glutamate formimino-transferase deficiency. In addition a hereditary disorder of intestinal folate transport has been described. Less well established are disorders of dihydrofolate reductase, methenyl-tetrahydrofolate cyclohydrolase, and defects of cellular folate uptake.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Apr
pubmed:issn
0340-6199
pubmed:author
pubmed:issnType
Print
pubmed:volume
157 Suppl 2
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
S60-6
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1998
pubmed:articleTitle
Genetic defects of folate and cobalamin metabolism.
pubmed:affiliation
University Children's Hospital, Basel, Switzerland.
pubmed:publicationType
Journal Article, Review, Research Support, Non-U.S. Gov't