Publication Date:
1989-04-07
Description:
Protein engineering and x-ray crystallography have been used to study the role of a surface loop that is present in pancreatic phospholipases but is absent in snake venom phospholipases. Removal of residues 62 to 66 from porcine pancreatic phospholipase A2 does not change the binding constant for micelles significantly, but it improves catalytic activity up to 16 times on micellar (zwitterionic) lecithin substrates. In contrast, the decrease in activity on negatively charged substrates is greater than fourfold. A crystallographic study of the mutant enzyme shows that the region of the deletion has a well-defined structure that differs from the structure of the wild-type enzyme. No structural changes in the active site of the enzyme were detected.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Kuipers, O P -- Thunnissen, M M -- de Geus, P -- Dijkstra, B W -- Drenth, J -- Verheij, H M -- de Haas, G H -- New York, N.Y. -- Science. 1989 Apr 7;244(4900):82-5.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Department of Biochemistry, University of Utrecht, The Netherlands.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/2704992" target="_blank"〉PubMed〈/a〉
Keywords:
Amino Acid Sequence
;
Animals
;
Crystallography
;
Enzyme Activation
;
Kinetics
;
Molecular Sequence Data
;
Mutation
;
Pancreas/enzymology
;
Phospholipases/*metabolism
;
Phospholipases A/genetics/*metabolism/physiology
;
Phospholipases A2
;
*Protein Conformation
;
Snake Venoms/analysis
;
Structure-Activity Relationship
;
Swine
Print ISSN:
0036-8075
Electronic ISSN:
1095-9203
Topics:
Biology
,
Chemistry and Pharmacology
,
Computer Science
,
Medicine
,
Natural Sciences in General
,
Physics
