Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
21
pubmed:dateCreated
1993-12-9
pubmed:abstractText
Cysteine site-directed mutagenesis was used to create variants of Escherichia coli ribosomal protein L7/L12 that have single cysteine substitutions, at residues 63 or 89, located in different exposed loops in the structure of the globular C-terminal domain indicated by the crystallographic structure. That structure shows a possible dimer interaction in which the two sites of cysteine substitution appear to be too distant for disulfide bond formation. After mild oxidation in solution both of the overexpressed purified cysteine-substituted proteins formed interchain disulfide crosslinked dimers in high yield. Both crosslinked dimers were fully active in restoring activity in poly(U)-directed polyphenylalanine synthesis to ribosomal core particles depleted of wild-type L7/L12. These results show that the two C-terminal domains have independent mobility. The activity of dimeric L7/L12 does not require the independent movement of the two globular C-terminal domains in an L7/L12 dimer; moreover, it appears independent of their mutual orientation when joined by crosslinking at the two loops. A third variant with a cysteine substitution at residue 33 near the junction between the alpha-helical N-terminal domain and the flexible hinge was prepared and tested. This protein was active in the protein synthesis assay in the reduced state. Oxidation produced the interchain crosslinked dimer in high yield, but this crosslinked dimer was inactive in polyphenylalanine synthesis. The inactivation was due to the inability of the Cys33-Cys33 oxidized dimer to bind to the core particle.
pubmed:grant
pubmed:commentsCorrections
http://linkedlifedata.com/resource/pubmed/commentcorrection/8234320-1390735, http://linkedlifedata.com/resource/pubmed/commentcorrection/8234320-1556104, http://linkedlifedata.com/resource/pubmed/commentcorrection/8234320-166641, http://linkedlifedata.com/resource/pubmed/commentcorrection/8234320-2121730, http://linkedlifedata.com/resource/pubmed/commentcorrection/8234320-2422172, http://linkedlifedata.com/resource/pubmed/commentcorrection/8234320-2581957, http://linkedlifedata.com/resource/pubmed/commentcorrection/8234320-2647737, http://linkedlifedata.com/resource/pubmed/commentcorrection/8234320-2656698, http://linkedlifedata.com/resource/pubmed/commentcorrection/8234320-2820061, http://linkedlifedata.com/resource/pubmed/commentcorrection/8234320-3126823, http://linkedlifedata.com/resource/pubmed/commentcorrection/8234320-3309338, http://linkedlifedata.com/resource/pubmed/commentcorrection/8234320-361399, http://linkedlifedata.com/resource/pubmed/commentcorrection/8234320-368343, http://linkedlifedata.com/resource/pubmed/commentcorrection/8234320-371980, http://linkedlifedata.com/resource/pubmed/commentcorrection/8234320-374953, http://linkedlifedata.com/resource/pubmed/commentcorrection/8234320-4333515, http://linkedlifedata.com/resource/pubmed/commentcorrection/8234320-4871609, http://linkedlifedata.com/resource/pubmed/commentcorrection/8234320-6130571, http://linkedlifedata.com/resource/pubmed/commentcorrection/8234320-6243579, http://linkedlifedata.com/resource/pubmed/commentcorrection/8234320-7026286, http://linkedlifedata.com/resource/pubmed/commentcorrection/8234320-7035682, http://linkedlifedata.com/resource/pubmed/commentcorrection/8234320-8419370
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Nov
pubmed:issn
0027-8424
pubmed:author
pubmed:issnType
Print
pubmed:day
1
pubmed:volume
90
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
9828-31
pubmed:dateRevised
2009-11-18
pubmed:meshHeading
pubmed:year
1993
pubmed:articleTitle
Escherichia coli ribosomal protein L7/L12 dimers remain fully active after interchain crosslinking of the C-terminal domains in two orientations.
pubmed:affiliation
Department of Biological Chemistry, School of Medicine, University of California, Davis 95616.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S.