Linked Life Data

11502180

Source:http://linkedlifedata.com/resource/pubmed/id/11502180

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
33
pubmed:dateCreated
2001-8-14
pubmed:databankReference
pubmed:abstractText
The structure of an active mutant of (S)-mandelate dehydrogenase (MDH-GOX2) from Pseudomonas putida has been determined at 2.15 A resolution. The membrane-associated flavoenzyme (S)-mandelate dehydrogenase (MDH) catalyzes the oxidation of (S)-mandelate to give a flavin hydroquinone intermediate which is subsequently reoxidized by an organic oxidant residing in the membrane. The enzyme was rendered soluble by replacing its 39-residue membrane-binding peptide segment with a corresponding 20-residue segment from its soluble homologue, glycolate oxidase (GOX). Because of their amphipathic nature and peculiar solubilization properties, membrane proteins are notoriously difficult to crystallize, yet represent a large fraction of the proteins encoded by genomes currently being deciphered. Here we present the first report of such a structure in which an internal membrane-binding segment has been replaced, leading to successful crystallization of the fully active enzyme in the absence of detergents. This approach may have general application to other membrane-bound proteins. The overall fold of the molecule is that of a TIM barrel, and it forms a tight tetramer within the crystal lattice that has circular 4-fold symmetry. The structure of MDH-GOX2 reveals how this molecule can interact with a membrane, although it is limited by the absence of a membrane-binding segment. MDH-GOX2 and GOX adopt similar conformations, yet they retain features characteristic of membrane and globular proteins, respectively. MDH-GOX2 has a distinctly electropositive surface capable of interacting with the membrane, while the opposite surface is largely electronegative. GOX shows no such pattern. MDH appears to form a new class of monotopic integral membrane protein that interacts with the membrane through coplanar electrostatic binding surfaces and hydrophobic interactions, thus combining features of both the prostaglandin synthase/squaline-hopine cyclase and the C-2 coagulation factor domain classes of membrane proteins.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Aug
pubmed:issn
0006-2960
pubmed:author
pubmed:issnType
Print
pubmed:day
21
pubmed:volume
40
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
9870-8
pubmed:dateRevised
2010-10-13
pubmed:meshHeading
pubmed-meshheading:11502180-Alcohol Oxidoreductases, pubmed-meshheading:11502180-Amino Acid Sequence, pubmed-meshheading:11502180-Binding Sites, pubmed-meshheading:11502180-Cell Membrane, pubmed-meshheading:11502180-Conserved Sequence, pubmed-meshheading:11502180-Crystallography, X-Ray, pubmed-meshheading:11502180-Flavins, pubmed-meshheading:11502180-Models, Molecular, pubmed-meshheading:11502180-Molecular Sequence Data, pubmed-meshheading:11502180-Mutation, pubmed-meshheading:11502180-Oxygen, pubmed-meshheading:11502180-Protein Binding, pubmed-meshheading:11502180-Protein Conformation, pubmed-meshheading:11502180-Protein Structure, Secondary, pubmed-meshheading:11502180-Protein Structure, Tertiary, pubmed-meshheading:11502180-Pseudomonas putida, pubmed-meshheading:11502180-Recombinant Fusion Proteins, pubmed-meshheading:11502180-Sequence Homology, Amino Acid
pubmed:year
2001
pubmed:articleTitle
Structure of an active soluble mutant of the membrane-associated (S)-mandelate dehydrogenase.
pubmed:affiliation
Department of Biochemistry and Molecular Biophysics, Washington University School of Medicine, St. Louis, Missouri 63110, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S.