title: ATP-mediated changes in cross-subunit interactions in the RecA protein.
abstract: RecA protein undergoes ATP- and DNA-induced conformational changes that result in different helical parameters for free protein filaments versus RecA/ATP/DNA nucleoprotein filaments. Previous mutational studies of a particular region of the RecA oligomeric interface suggested that cross-subunit contacts made by residues K6 and R28 were more important for stabilization of free protein oligomers than nucleoprotein filaments [Eldin, S., et al. (2000) J. Mol. Biol. 299, 91-101]. Using mutant proteins with specifically engineered Cys substitutions, we show here that the efficiency of cross-subunit disulfide bond formation at certain positions in this region changes in the presence of ATP or ATP/DNA. Our results support the idea that specific cross-subunit interactions that occur within this region of the subunit interface are different in free RecA protein versus RecA/ATP/DNA nucleoprotein filaments.
authors.affiliation: Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, 55 Lake Avenue North, Worcester, Massachusetts 01655-0103, USA.
authors.forename: K M
authors.initials: KM
authors.lastname: Logan
authors.forename: A L
authors.initials: AL
authors.lastname: Forget
authors.forename: J P
authors.initials: JP
authors.lastname: Verderese
authors.forename: K L
authors.initials: KL
authors.lastname: Knight
mesh_terms: D000255:Adenosine Triphosphate / Q000378:metabolism*; D019943:Amino Acid Substitution; D010584:Bacteriophage phi X 174 / Q000235:genetics; D018360:Crystallography, X-Ray; D004249:DNA Damage; D004277:DNA, Single-Stranded / Q000737:chemistry / Q000528:radiation effects / Q000648:ultrastructure; D004279:DNA, Viral / Q000737:chemistry* / Q000528:radiation effects / Q000648:ultrastructure; D019281:Dimerization; D004220:Disulfides / Q000032:analysis; D004926:Escherichia coli / Q000235:genetics / Q000378:metabolism; D008958:Models, Molecular; D010957:Plasmids; D011487:Protein Conformation; D017433:Protein Structure, Secondary; D021122:Protein Subunits; D011938:Rec A Recombinases / Q000737:chemistry* / Q000648:ultrastructure; D011994:Recombinant Proteins / Q000737:chemistry / Q000528:radiation effects / Q000648:ultrastructure; D014466:Ultraviolet Rays
chemical_list: D004277:DNA, Single-Stranded; D004279:DNA, Viral; D004220:Disulfides; D021122:Protein Subunits; D011994:Recombinant Proteins; D000255:Adenosine Triphosphate; D011938:Rec A Recombinases