Linked Life Data

17289169

Source:http://linkedlifedata.com/resource/pubmed/id/17289169

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
2007-3-5
pubmed:abstractText
Cryptosporidosis is a severe opportunistic infection of immuno-compromised individuals for which no reliable therapy exists. The parasite scavenges host-derived polyamines, particularly spermine, which is then converted to the lower polyamines by the combined action of spermidine/spermine N(1)-acetyltransferase (SSAT) and polyamine oxidase (PAO). We have isolated and expressed the Cryptosporidium parvum SSAT for kinetic and molecular comparison with the host enzyme. The CpSSAT is a homotetramer with a subunit molecular mass of 18 kDa and low sequence similarity to higher eukaryotes but maintains the critical arginine residues in the active site. The CpSSAT had an activity of 299 nmol(-1)min(-1)(mg of protein)(-1) and exhibits an ordered Bi-Bi kinetics with preferred substrate specificity for spermine. Polyamine analogues having unsaturated central carbons were found to exhibit mixed inhibition kinetics of the CpSSAT. The cis-analogues were more effective inhibitors of the CpSSAT with lower K(i) values than the trans-analogues. Experiments aimed at determining the ratio of the time of the analogue in the enzyme active site to that spent out (in-out time: delta ln E/deltat) confirmed the higher efficiency of the cis-analogues as inhibitors of the CpSSAT. The results of this study reveal that the C. parvum SSAT may provide a rational target for drug design.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Apr
pubmed:issn
0166-6851
pubmed:author
pubmed:issnType
Print
pubmed:volume
152
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
170-80
pubmed:dateRevised
2007-12-3
pubmed:meshHeading
pubmed:year
2007
pubmed:articleTitle
Cryptosporidium parvum spermidine/spermine N1-acetyltransferase exhibits different characteristics from the host enzyme.
pubmed:affiliation
Haskins Laboratories, Pace University, New York, NY 10038, USA. nyarlett@pace.edu
pubmed:publicationType
Journal Article, Comparative Study, Research Support, Non-U.S. Gov't, Research Support, N.I.H., Extramural