JB
Home Help [Feedback] [For Subscribers] [Archive] [Search] [Contents]
This Article
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrowReprints and Permissions
Right arrow Copyright Information
Right arrow Books from ASM Press
Right arrow MicrobeWorld
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Clark, A J
Right arrow Articles by Cohen, A
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Clark, A J
Right arrow Articles by Cohen, A
J Bacteriol. 1993 December; 175(23): 7673-7682

research-article

Genetic and molecular analyses of the C-terminal region of the recE gene from the Rac prophage of Escherichia coli K-12 reveal the recT gene.

A J Clark, V Sharma, S Brenowitz, C C Chu, S Sandler, L Satin, A Templin, I Berger and A Cohen

Department of Molecular and Cell Biology, Barker/Koshland ASU, University of California, Berkeley 94720.

ABSTRACT

The nucleotide sequence of the C-terminal region of the recE gene of the Rac prophage of Escherichia coli K-12 reveals the presence of a partially overlapping reading frame we call recT. Deletion mutations show that recT is required for the RecE pathway of conjugational recombination. By cloning recT with a plasmid vector compatible with pBR322, we showed by cis-trans tests that the portion of the recE gene encoding ExoVIII DNA nuclease activity is also required for RecE pathway conjugational recombination. The recT gene can replace the redB gene of lambda for recA-independent plasmid recombination. A Tn10 insertion mutation previously thought to be in recE is located in recT and is renamed recT101::Tn10. Discrepancies between the molecular mass estimates of wild-type ExoVIII protein determined from mobility in sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and calculated from the predicted amino acid sequence are discussed. The hypothesis that wild-type ExoVIII protein results from fusion of RecE and RecT proteins is disproved genetically, thus supporting a previous hypothesis that the discrepancies are due to abnormal protein mobility in SDS-PAGE. A computer-performed scan of the bacteriophage nucleotide sequence data base of GenBank revealed substantial similarity between most of recE and a 2.5-kb portion of the b2 region of lambda. This suggests interesting speculations concerning the evolutionary relationship of lambda and Rac prophages.

J Bacteriol. 1993 December; 175(23): 7673-7682




This article has been cited by other articles:



Home Help [Feedback] [For Subscribers] [Archive] [Search] [Contents]
Appl. Environ. Microbiol. Infect. Immun. Eukaryot. Cell
Mol. Cell. Biol. J. Virol. Microbiol. Mol. Biol. Rev.
ALL ASM JOURNALS

Copyright © 1993 by the American Society for Microbiology. All rights reserved.