TY - JOUR
T1 - RecBCD-dependent joint molecule formation promoted by the Escherichia coli RecA and SSB proteins
AU - Roman, Linda J.
AU - Dixon, Dan A.
AU - Kowalczykowski, Stephen C.
N1 - Copyright:
Copyright 2017 Elsevier B.V., All rights reserved.
PY - 1991
Y1 - 1991
N2 - We describe the formation of homologously paired joint molecules in an in vitro reaction that is dependent on the concerted actions of purified RecA and RecBCD proteins and is stimulated by single-stranded DNA-binding protein (SSB). RecBCD enzyme initiates the process by unwinding the linear double-stranded DNA to produce single-stranded DNA, which is trapped by SSB and RecA. RecA uses this single-stranded DNA to catalyze the invasion of a supercoiled double-stranded DNA molecule, forming a homologously paired joint molecule. At low RecBCD enzyme concentrations, the rate-limiting step is the unwinding of duplex DNA by RecBCD, whereas at higher RecBCD concentrations, the rate-limiting step is RecA-catalyzed strand invasion. The behavior of mutant RecA proteins in this in vitro reaction parallels their in vivo phenotypes, suggesting that this reaction may define biochemical steps that occur during homologous recombination by the RecBCD pathway in vivo.
AB - We describe the formation of homologously paired joint molecules in an in vitro reaction that is dependent on the concerted actions of purified RecA and RecBCD proteins and is stimulated by single-stranded DNA-binding protein (SSB). RecBCD enzyme initiates the process by unwinding the linear double-stranded DNA to produce single-stranded DNA, which is trapped by SSB and RecA. RecA uses this single-stranded DNA to catalyze the invasion of a supercoiled double-stranded DNA molecule, forming a homologously paired joint molecule. At low RecBCD enzyme concentrations, the rate-limiting step is the unwinding of duplex DNA by RecBCD, whereas at higher RecBCD concentrations, the rate-limiting step is RecA-catalyzed strand invasion. The behavior of mutant RecA proteins in this in vitro reaction parallels their in vivo phenotypes, suggesting that this reaction may define biochemical steps that occur during homologous recombination by the RecBCD pathway in vivo.
KW - Genetic recombination
KW - Homologous pairing
KW - Single-stranded DNA-binding protein
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U2 - 10.1073/pnas.88.8.3367
DO - 10.1073/pnas.88.8.3367
M3 - Article
C2 - 2014257
AN - SCOPUS:0026351806
VL - 88
SP - 3367
EP - 3371
JO - Proceedings of the National Academy of Sciences of the United States of America
JF - Proceedings of the National Academy of Sciences of the United States of America
SN - 0027-8424
IS - 8
ER -