Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
1988-11-16
pubmed:abstractText
Although a wide range of aminoacyl-7-amino-4-methylcoumarin derivatives (which are used to measure aminopeptidase activity) were found to be hydrolysed by human skeletal muscle soluble fraction, fractionation of the latter via anion-exchange and gel-filtration chromatography resolved only five types of separable aminopeptidase (with activity relative to alanyl aminopeptidase in parentheses): alanyl aminopeptidase (alpha-aminoacyl-peptide hydrolase, EC 3.4.11.14, 100%), arginyl aminopeptidase (two isoenzymes, L-arginyl-L-lysyl)-peptide hydrolase, EC 3.4.11.6, 15%); pyroglutamyl aminopeptidase (5-oxoprolyl-peptide hydrolase, EC 3.4.19.3, 3%); leucyl aminopeptidase (alpha-aminoacyl-peptide hydrolase (cytosol), EC 3.4.11.1, 1.5%) and alpha-glutamyl aminopeptidase (0.2%). Thus over 80% of the total aminopeptidase activity (expressed in relative terms) in human skeletal muscle soluble fraction can be accounted for by a single enzyme, the major aminopeptidase. A single peak of activity, which co-eluted with the major aminopeptidase after anion-exchange and gel-filtration chromatography, was obtained after assay with the following aminoacyl-7-amino-4-methylcoumarin derivatives: glycyl-, isoleucyl-, lysyl-, methionyl-, ornithyl-, phenylalanyl-, prolyl-, seryl-, tyrosyl- and valyl-. Thus, the hydrolysis of these derivatives by skeletal muscle soluble fraction occurs principally via the major aminopeptidase and not by specific enzymes, as previously suggested (Wada and Aoyagi, 1983). These results illustrate the difficulty in measuring individual aminopeptidase activities in muscle homogenate and soluble fraction, and the danger in ascribing apparent aminopeptidase activity to 'specific' enzymes.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Oct
pubmed:issn
0006-3002
pubmed:author
pubmed:issnType
Print
pubmed:day
12
pubmed:volume
956
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
300-6
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1988
pubmed:articleTitle
Rationalization of aminopeptidase activities in human skeletal muscle soluble extract.
pubmed:affiliation
Neurochemistry Department, Newcastle General Hospital, Newcastle upon Tyne, U.K.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't