Publication Date:
1988-08-05
Description:
The x-ray structures of the allosteric enzyme aspartate transcarbamylase from Escherichia coli have been solved and refined for both allosteric forms. The T form was determined in the presence of the heterotropic inhibitor cytidine triphosphate, CTP, while the R form was determined in the presence of the bisubstrate analog N-phosphonacetyl-L-aspartate. These two x-ray structures provide the starting point for an understanding of how allosteric enzymes are able to control the rates of metabolic pathways. Insights into the mechanisms of both catalysis and homotropic cooperativity have been obtained by using site-directed mutagenesis to probe residues thought to be critical to the function of the enzyme based on these x-ray structures.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Kantrowitz, E R -- Lipscomb, W N -- GM 06920/GM/NIGMS NIH HHS/ -- GM26237/GM/NIGMS NIH HHS/ -- New York, N.Y. -- Science. 1988 Aug 5;241(4866):669-74.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Department of Chemistry, Boston College, MA 02167.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/3041592" target="_blank"〉PubMed〈/a〉
Keywords:
Allosteric Regulation
;
Allosteric Site
;
Aspartate Carbamoyltransferase/*physiology
;
Binding Sites
;
Chemical Phenomena
;
Chemistry
;
Escherichia coli/*enzymology
;
Macromolecular Substances
;
Protein Conformation
;
Structure-Activity Relationship
Print ISSN:
0036-8075
Electronic ISSN:
1095-9203
Topics:
Biology
,
Chemistry and Pharmacology
,
Computer Science
,
Medicine
,
Natural Sciences in General
,
Physics
