Source:http://linkedlifedata.com/resource/pubmed/id/11402022
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| Predicate | Object |
|---|---|
| rdf:type | |
| lifeskim:mentions | |
| pubmed:issue |
34
|
| pubmed:dateCreated |
2001-8-20
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| pubmed:databankReference | |
| pubmed:abstractText |
The crystal structure of the MJ0796 ATP-binding cassette, a member of the o228/LolD transporter family, has been determined at 2.7-A resolution with MgADP bound at its active site. Comparing this structure with that of the ATP-bound form of the HisP ATP-binding cassette (Hung, L. W., Wang, I. X., Nikaido, K., Liu, P. Q., Ames, G. F., and Kim, S. H. (1998) Nature 396, 703-707) shows a 5-A withdrawal of a phylogenetically invariant glutamine residue from contact with the gamma-phosphate of ATP in the active site. This glutamine is located in a protein segment that links the rigid F(1)-type ATP-binding core of the enzyme to an ABC transporter-specific alpha-helical subdomain that moves substantially away from the active site in the MgADP-bound structure of MJ0796 compared with the ATP-bound structure of HisP. A similar conformational effect is observed in the MgADP-bound structure of MJ1267 (Karpowich, N., et al. (2001) Structure, in press), establishing the withdrawal of the glutamine and the coupled outward rotation of the alpha-helical subdomain as consistent consequences of gamma-phosphate release from the active site of the transporter. Considering this subdomain movement in the context of a leading model for the physiological dimer of cassettes present in ABC transporters indicates that it produces a modest mechanical change that is likely to play a role in facilitating nucleotide exchange out of the ATPase active site. Finally, it is noteworthy that one of the intersubunit packing interactions in the MJ0796 crystal involves antiparallel beta-type hydrogen bonding interactions between the outermost beta-strands in the two core beta-sheets, leading to their fusion into a single extended beta-sheet, a type of structural interaction that has been proposed to play a role in mediating the aggregation of beta-sheet-containing proteins.
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| pubmed:language |
eng
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| pubmed:journal | |
| pubmed:citationSubset |
IM
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| pubmed:chemical | |
| pubmed:status |
MEDLINE
|
| pubmed:month |
Aug
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| pubmed:issn |
0021-9258
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| pubmed:author | |
| pubmed:issnType |
Print
|
| pubmed:day |
24
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| pubmed:volume |
276
|
| pubmed:owner |
NLM
|
| pubmed:authorsComplete |
Y
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| pubmed:pagination |
32313-21
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| pubmed:dateRevised |
2006-11-15
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| pubmed:meshHeading |
pubmed-meshheading:11402022-ATP-Binding Cassette Transporters,
pubmed-meshheading:11402022-Adenosine Diphosphate,
pubmed-meshheading:11402022-Adenosine Triphosphate,
pubmed-meshheading:11402022-Amino Acid Sequence,
pubmed-meshheading:11402022-Binding Sites,
pubmed-meshheading:11402022-Crystallography, X-Ray,
pubmed-meshheading:11402022-Models, Molecular,
pubmed-meshheading:11402022-Molecular Sequence Data,
pubmed-meshheading:11402022-Phylogeny,
pubmed-meshheading:11402022-Protein Conformation,
pubmed-meshheading:11402022-Sequence Homology, Amino Acid
|
| pubmed:year |
2001
|
| pubmed:articleTitle |
The crystal structure of the MJ0796 ATP-binding cassette. Implications for the structural consequences of ATP hydrolysis in the active site of an ABC transporter.
|
| pubmed:affiliation |
Department of Biological Sciences, Columbia University, New York, New York 10027, USA.
|
| pubmed:publicationType |
Journal Article,
Research Support, U.S. Gov't, P.H.S.,
Research Support, Non-U.S. Gov't
|