Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
25
pubmed:dateCreated
1988-5-3
pubmed:abstractText
The crystal structures of metyrapone- and 1-, 2-, and 4-phenylimidazole-inhibited complexes of cytochrome P-450cam have been refined to a nominal resolution of 2.1 A and compared with the 1.63-A camphor-bound structure. With the exception of 2-phenylimidazole, each of the inhibitors forms an N-Fe bond with the heme iron atom while part of the inhibitor sits in the camphor-binding pocket. In the 2-phenylimidazole complex, a water molecule or hydroxide ion coordinates with the heme iron atom while the inhibitor binds in the camphor pocket adjacent to the aqua ligand. Each of the inhibitors forces the central region of helix I that forms part of the O2 binding pocket to move away from the inhibitor, with the exception of 2-phenylimidazole where the helix moves in toward the inhibitor. In addition, the Tyr-96 region, which provides specific contact points with the substrate, is perturbed, although to varying degrees with each inhibitor. These perturbations include large, localized changes in Debye-Waller or temperature factors, indicative of changes in dynamical fluctuations. The largest inhibitor, metyrapone, causes the fewest changes, while 2-phenylimidazole binding causes the largest, especially in helix I. The large 2-phenylimidazole-induced movement of helix I can be rationalized on the basis of the inhibitor imidazole group's hydrogen-bonding requirements.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Dec
pubmed:issn
0006-2960
pubmed:author
pubmed:issnType
Print
pubmed:day
15
pubmed:volume
26
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
8165-74
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1987
pubmed:articleTitle
Crystal structures of metyrapone- and phenylimidazole-inhibited complexes of cytochrome P-450cam.
pubmed:affiliation
Protein Engineering Department, Genex Corporation, Gaithersburg, Maryland 20877.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S.