Accession Number : AD0713563

Title :   CONFORMATIONAL STUDIES ON THE ACTIVE SITE OF ACETYLCHOLINESTERASE BY ELECTRON PARAMAGNETIC RESONANCE,

Corporate Author : EDGEWOOD ARSENAL MD

Personal Author(s) : Morrisett,Joel D. ; Broomfield,Clarence A. ; Hackley,Brennie E. , Jr

Report Date : 1970

Pagination or Media Count : 15

Abstract : Poisoning by 'refractory' anticholinesterases is not reversed by oxime therapy because of the phenomenon of 'ageing', the spontaneous dealkoxylation or dealkylation from the phosphonyl group attached to the active site serine residue. The research concerns the studies directed toward the elucidation of structure-function relationships in this enzyme. In particular, the authors were interested in the geometry and stereochemistry of the active site. Using spin labeled electron paramagnetic resonance, the authors gained several new pieces of information about the active site of acetylcholinesterase. First, the active site appears to be quite spacious and/or located superficially on the enzyme. Second, the conformation at the active site is detectably, but not greatly affected by removing the enzyme molecule from the membrane. Third, there appears to be on the membrane a sulfhydryl group located close enough to the active site of the membrane-bound enzyme to interact with the attached nitroxyl radical. (Author)

Descriptors :   (*ACETYLCHOLINESTERASE, *PARAMAGNETIC RESONANCE), (*MOLECULAR STRUCTURE, ACETYLCHOLINESTERASE), CHEMICAL REACTIONS, ORGANIC PHOSPHORUS COMPOUNDS, CHEMICAL WARFARE AGENTS

Subject Categories : Biochemistry
      Chemical, Biological and Radiological Warfare

Distribution Statement : APPROVED FOR PUBLIC RELEASE