Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
5
pubmed:dateCreated
2001-11-8
pubmed:databankReference
pubmed:abstractText
We present a refined model of the alpha beta-tubulin dimer to 3.5 A resolution. An improved experimental density for the zinc-induced tubulin sheets was obtained by adding 114 electron diffraction patterns at 40-60 degrees tilt and increasing the completeness of structure factor amplitudes to 84.7 %. The refined structure was obtained using maximum-likelihood including phase information from experimental images, and simulated annealing Cartesian refinement to an R-factor of 23.2 and free R-factor of 29.7. The current model includes residues alpha:2-34, alpha:61-439, beta:2-437, one molecule of GTP, one of GDP, and one of taxol, as well as one magnesium ion at the non-exchangeable nucleotide site, and one putative zinc ion near the M-loop in the alpha-tubulin subunit. The acidic C-terminal tails could not be traced accurately, neither could the N-terminal loop including residues 35-60 in the alpha-subunit. There are no major changes in the overall fold of tubulin with respect to the previous structure, testifying to the quality of the initial experimental phases. The overall geometry of the model is, however, greatly improved, and the position of side-chains, especially those of exposed polar/charged groups, is much better defined. Three short protein sequence frame shifts were detected with respect to the non-refined structure. In light of the new model we discuss details of the tubulin structure such as nucleotide and taxol binding sites, lateral contacts in zinc-sheets, and the significance of the location of highly conserved residues.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Nov
pubmed:issn
0022-2836
pubmed:author
pubmed:copyrightInfo
Copyright 2001 Academic Press.
pubmed:issnType
Print
pubmed:day
9
pubmed:volume
313
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1045-57
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed-meshheading:11700061-Amino Acid Sequence, pubmed-meshheading:11700061-Binding Sites, pubmed-meshheading:11700061-Conserved Sequence, pubmed-meshheading:11700061-Crystallography, X-Ray, pubmed-meshheading:11700061-Dimerization, pubmed-meshheading:11700061-GTP Phosphohydrolases, pubmed-meshheading:11700061-Guanosine Triphosphate, pubmed-meshheading:11700061-Magnesium, pubmed-meshheading:11700061-Models, Molecular, pubmed-meshheading:11700061-Molecular Sequence Data, pubmed-meshheading:11700061-Paclitaxel, pubmed-meshheading:11700061-Protein Binding, pubmed-meshheading:11700061-Protein Structure, Quaternary, pubmed-meshheading:11700061-Protein Structure, Secondary, pubmed-meshheading:11700061-Protein Subunits, pubmed-meshheading:11700061-Sequence Alignment, pubmed-meshheading:11700061-Tubulin, pubmed-meshheading:11700061-Zinc
pubmed:year
2001
pubmed:articleTitle
Refined structure of alpha beta-tubulin at 3.5 A resolution.
pubmed:affiliation
MRC Laboratory of Molecular Biology, Cambridge, UK.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, U.S. Gov't, Non-P.H.S.