Linked Life Data

8988003

Source:http://linkedlifedata.com/resource/pubmed/id/8988003

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
51
pubmed:dateCreated
1997-1-30
pubmed:abstractText
Fluorescence methods were utilized to study dynamic aspects of the 24 kDa dimeric Escherichia coli ribosomal protein L7/L12. Oligonucleotide site-directed mutagenesis was used to introduce cysteine residues at specific locations along the peptide chain, in both the C-terminal and N-terminal domains, and various sulfhydryl reactive fluorescence probes (iodoacetamido) fluorescein, IAEDANS, pyrenemethyl iodoacetate) were attached to these residues. In addition to the full-length proteins, a hinge-deleted variant and variants corresponding to the C-terminal fragment and the N-terminal fragment were also studied. Both steady-state and time-resolved fluorescence measurements were carried out, and the results demonstrated that L7/L12 is not a rigid molecule. Specifically, the two C-terminal domains move freely with respect to one another and with respect to the dimeric N-terminal domain. Removal of the hinge region, however, significantly reduces the mobility of the C-terminal domains. The data also show that the rotational relaxation time monitored by the fluorescent probe-depends upon the probe's excited state lifetime. This observation is interpreted to indicate that a hierarchy of motions exists in the L7/L12 molecule including facile motions of the C-terminal domains and dimeric N-terminal domain, in addition to the overall tumbling of the protein. Probes attached to the N-terminal domain exhibit global rotational relaxation times consistent with the molecular mass of the dimeric N-terminal fragment. Upon reconstitution of labeled L7/L12 with ribosomal cores, however, the motion associated with the dimeric N-terminal domain is greatly diminished while the facile motion of the C-terminal domains is almost unchanged.
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
24
pubmed:volume
35
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
16672-9
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1996
pubmed:articleTitle
Rotational and conformational dynamics of Escherichia coli ribosomal protein L7/L12.
pubmed:affiliation
Department of Biochemistry and Biophysics, University of Hawaii, Honolulu 96822, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, U.S. Gov't, Non-P.H.S.