Linked Life Data

8409770

Source:http://linkedlifedata.com/resource/pubmed/id/8409770

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
8
pubmed:dateCreated
1993-11-9
pubmed:abstractText
Lipoprotein lipase (LPL) and hepatic lipase (HL) mediate the hydrolysis of triglycerides and phospholipids present in circulating lipoprotein particles and are essential for normal lipid metabolism. Both enzymes have a similar primary amino acid structure and share requirements for intact catalytic, lipid binding, and heparin binding domains. However, LPL and HL exhibit different substrate specificities and cofactor requirements. In order to characterize the functional domains necessary for LPL activity, a chimeric lipase consisting of the amino-terminal 314 amino acids of human LPL and the carboxyl-terminal 146 amino acids of human HL was synthesized by joining the cDNA of both lipases at the 5'-end of exon 7. Northern blot hybridization and Western blot analyses revealed the size of the chimera mRNA and protein to be approximately 1.5 kb and 55 kDa, respectively. The chimeric enzyme hydrolyzed both long chain and short chain fatty acid triacylglycerols and had catalytic properties that were similar to lipoprotein lipase. Thus, apolipoprotein (apo)C-II was required for maximal lipase activity, and high salt concentration abolished the ability of the chimera to hydrolyze triolein even in the presence of apoC-II. A monospecific anti-HL polyclonal antibody interacting with the C-terminal HL-derived domain of the chimeric enzyme abolished the enzyme's ability to hydrolyze triglyceride emulsion but not tributyrin substrates. Analysis of the heparin binding properties of the chimeric enzyme using heparin-Sepharose affinity chromatography revealed an elution pattern which was intermediate between that of lipoprotein and hepatic lipase. In summary, we have characterized the functional properties of an LPL-HL chimeric enzyme.(ABSTRACT TRUNCATED AT 250 WORDS)
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Aug
pubmed:issn
0022-2275
pubmed:author
pubmed:issnType
Print
pubmed:volume
34
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1393-40
pubmed:dateRevised
2007-11-15
pubmed:meshHeading
pubmed-meshheading:8409770-Base Sequence, pubmed-meshheading:8409770-Binding Sites, pubmed-meshheading:8409770-Catalysis, pubmed-meshheading:8409770-Cell Line, pubmed-meshheading:8409770-Culture Media, Conditioned, pubmed-meshheading:8409770-Embryo, Mammalian, pubmed-meshheading:8409770-Fatty Acids, pubmed-meshheading:8409770-Genetic Engineering, pubmed-meshheading:8409770-Heparin, pubmed-meshheading:8409770-Humans, pubmed-meshheading:8409770-Kidney, pubmed-meshheading:8409770-Lipase, pubmed-meshheading:8409770-Lipoprotein Lipase, pubmed-meshheading:8409770-Liver, pubmed-meshheading:8409770-Molecular Sequence Data, pubmed-meshheading:8409770-Recombinant Fusion Proteins, pubmed-meshheading:8409770-Substrate Specificity, pubmed-meshheading:8409770-Transfection, pubmed-meshheading:8409770-Triglycerides, pubmed-meshheading:8409770-Triolein
pubmed:year
1993
pubmed:articleTitle
Functional characterization of a chimeric lipase genetically engineered from human lipoprotein lipase and human hepatic lipase.
pubmed:affiliation
Molecular Disease Branch, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD 20892.
pubmed:publicationType
Journal Article, Comparative Study, Research Support, U.S. Gov't, P.H.S.