Linked Life Data

6654852

Source:http://linkedlifedata.com/resource/pubmed/id/6654852

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
4
pubmed:dateCreated
1984-2-24
pubmed:abstractText
Two novel aminopeptidases (I and II) which have specificity for amino-terminal arginine residues and strong sensitivity to divalent cations were purified from Streptococcus mitis ATCC 9811 by a procedure that involved treatment with a lytic enzyme for bacterial cell walls, followed by a series of chromatographies. Enzyme I was obtained as a homogeneous protein as judged by polyacrylamide gel electrophoresis and had a specific activity of 484.8 units per mg protein using L-arginine-2-naphthylamide as substrate; its Km value was 2.6 X 10(-5) M. The molecular weight was estimated to be 62,000, and its isoelectric point was pH 4.4. Enzyme II was purified to a specific activity of 128.0 units per mg protein and had a Km value of 3.8 X 10(-5) M. The molecular weight was estimated to be 360,000, and its isoelectric point was pH 5.7. The pH optima of enzymes I and II were 8.6 and 7.6, respectively. Both enzymes were inactivated by sulfhydryl reagents and metal ions but were markedly activated by EDTA. The chloride ion had an inhibitory rather than a stimulatory effect on the activity of both enzymes. Substrate specificity studies indicated that both the enzymes specifically hydrolyze N-terminal arginine residues from a-aminoacyl 2-naphthylamides and peptides, but they could not attack the L-arginyl-L-prolyl-peptide.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Oct
pubmed:issn
0021-924X
pubmed:author
pubmed:issnType
Print
pubmed:volume
94
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1201-8
pubmed:dateRevised
2007-12-19
pubmed:meshHeading
pubmed:year
1983
pubmed:articleTitle
Purification and characterization of two novel arginine aminopeptidases from Streptococcus mitis ATCC 9811.
pubmed:publicationType
Journal Article, Comparative Study