Mutational analysis of the functional motifs of RuvB, an AAA+ class helicase and motor protein for holliday junction branch migration.
Escherichia coli RuvB protein, together with RuvA, promotes branch migration of Holliday junctions during homologous recombination and recombination repair. The RuvB molecular motor is an intrinsic ATP-dependent DNA helicase with a hexameric ring structure and its architecture has been suggested to be related to those of the members of the AAA+ protein class. In this study, we isolated a large number of plasmids carrying ruvB mutant genes and identified amino acid residues important for the RuvB functions by examining the in vivo DNA repair activities of the mutant proteins. Based on these mutational studies and amino acid conservation among various RuvBs, we identified 10 RuvB motifs that agreed well with the features of the AAA+ protein class and that distinguished the primary structure of RuvB from that of typical DNA/RNA helicases with seven conserved helicase motifs.
Iwasaki
H
H
Department of Molecular Microbiology, Research Institute for Microbial Diseases, Osaka University, Suita, Osaka 565-0871, Japan. iwasaki@biken.osaka-u.ac.jp
Han
Y W
YW
Okamoto
T
T
Ohnishi
T
T
Yoshikawa
M
M
Yamada
K
K
Toh
H
H
Daiyasu
H
H
Ogura
T
T
Shinagawa
H
H
D000595:Amino Acid Sequence; D001426:Bacterial Proteins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism*; D001483:Base Sequence; D017124:Conserved Sequence; D004265:DNA Helicases / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D004260:DNA Repair; D004269:DNA, Bacterial / Q000235:genetics / Q000528:radiation effects; D004926:Escherichia coli / Q000201:enzymology / Q000235:genetics*; D008969:Molecular Sequence Data; D016297:Mutagenesis, Site-Directed; D010957:Plasmids; D016133:Polymerase Chain Reaction; D011994:Recombinant Proteins / Q000737:chemistry / Q000378:metabolism; D015183:Restriction Mapping; D016415:Sequence Alignment; D017386:Sequence Homology, Amino Acid; D014466:Ultraviolet Rays
D001426:Bacterial Proteins; D004269:DNA, Bacterial; D011994:Recombinant Proteins; C061260:RuvB protein, Bacteria; D004265:DNA Helicases