Linked Life Data

1552908

Source:http://linkedlifedata.com/resource/pubmed/id/1552908

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
1992-4-30
pubmed:abstractText
Mutants able to grow in the presence of 1.2 mg/ml streptomycin were isolated from Escherichia coli WP2 after exposure to ultraviolet light (UV) or in the absence of any treatment (spontaneous), and from a umuC derivative after exposure to UV and delayed photoreversal. These mutants, characterized as streptomycin resistant (Smr) or dependent (Smd), carry mutations in the rpsL gene. This gene was amplified using the polymerase chain reaction and sequenced. Mutations induced by UV were largely (76%) of the Smr phenotype, all of which were changes at an A:T base pair at codons 42 or 87. Mutations induced by UV plus delayed photoreversal in the non-UV-mutable umuC122 derivative of WP2 were exclusively of the Smd phenotype and all occurred at G:C base pairs at codons 41, 90 or 91. These results are consistent with current understanding of the mechanism of mutagenesis by UV and delayed photoreversal. A broader spectrum of mutations was seen in the spontaneous series including three-base deletions leading to amino acid loss (2 of codon 93, 1 of codon 87). Of particular note was the number of intragenic second site mutations in the spontaneous series, most if not all of which appeared to be silent with respect to streptomycin phenotype. It is necessary to postulate a high rate of formation of such mutations at some stage during the experiment. One possibility is that spontaneous mutation may often occur in bursts when an error correction mechanism (eg., proofreading, mismatch correction) is temporarily inactive.(ABSTRACT TRUNCATED AT 250 WORDS)
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Mar
pubmed:issn
0026-8925
pubmed:author
pubmed:issnType
Print
pubmed:volume
232
pubmed:geneSymbol
rpsL, strA
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
89-96
pubmed:dateRevised
2000-12-18
pubmed:meshHeading
pubmed:year
1992
pubmed:articleTitle
Mutant sequences in the rpsL gene of Escherichia coli B/r: mechanistic implications for spontaneous and ultraviolet light mutagenesis.
pubmed:affiliation
MRC Cell Mutation Unit, University of Sussex, Falmer, Brighton, Great Britain.
pubmed:publicationType
Journal Article