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OLS Field Name OLS Field Data
Main Title DNA Sequence Analysis of Revertants of the 'hisD3052' Allele of 'Salmonella typhimurium' TA98 Using the Polymerase Chain Reaction and Direct Sequencing: Application to 1-Nitropyrene-Induced Revertants.
Author Bell, D. A. ; Levine, J. G. ; DeMarini., D. M. ;
CORP Author Health Effects Research Lab., Research Triangle Park, NC. Genetic Toxicology Div.
Publisher c1991
Year Published 1991
Report Number EPA/600/J-91/098;
Stock Number PB91-200329
Additional Subjects Bacterial DNA ; Salmonella typhimurium ; Mutation ; Polymerase chain reaction ; Alleles ; Base sequence ; Metabolic activation ; Single-stranded DNA ; Nucleic acid conformation ; Agar gel electrophoresis ; Reprints ; 1-Nitropyrene
Holdings
Library Call Number Additional Info Location Last
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Status
NTIS  PB91-200329 Most EPA libraries have a fiche copy filed under the call number shown. Check with individual libraries about paper copy. NTIS 09/04/1991
Collation 12p
Abstract
The study used the polymerase chain reaction (PCR) to speed the processing of revertants of Salmonella typhimurium TA98 for DNA sequence analysis. Briefly, a crude DNA extract from a single colony was prepared and used in an asymmetric PCR to amplify a 228-bp fragment containing the hisD3052 mutation approximately in the center. Following ultra-filtration, the ssDNA was sequenced using an end-labeled probe and dideoxy sequencing. The most frequent mutation among the revertants was a -2 deletion of GC or CG within the sequence CGCGCGCG, which is upstream of the hisD3052 mutation. The deletion occurred in 38% (6/16) of the spontaneous (-S9) revertants and in 94% (15/16) of a set of 1-nitropyrene-induced revertants. Misalignment of complementary DNA strands within this repeat may account for this mutation, although the possible formation of Z-DNA within this region may also play a role. Other mutations, mostly deletions but also some complex mutations (insertions/deletions/substitutions), occurred within quasi-palindromic regions of DNA. The potential DNA secondary structures within such regions may mediate the templated production of some of these mutations.