TY - JOUR
T1 - Novel essential residues of Hda for interaction with DnaA in the regulatory inactivation of DnaA
T2 - Unique roles for Hda AAA+ Box VI and VII motifs
AU - Nakamura, Kenta
AU - Katayama, Tsutomu
N1 - Copyright:
Copyright 2015 Elsevier B.V., All rights reserved.
PY - 2010/4
Y1 - 2010/4
N2 - Summary Escherichia coli ATP-DnaA initiates chromosomal replication. For preventing extra-initiations, a complex of ADP-Hda and the DNA-loaded replicase clamp promotes DnaA-ATP hydrolysis, yielding inactive ADP-DnaA. However, the Hda-DnaA interaction mode remains unclear except that the Hda Box VII Arg finger (Arg-153) and DnaA sensor II Arg-334 within each AAA+ domain are crucial for the DnaA-ATP hydrolysis. Here, we demonstrate that direct and functional interaction of ADP-Hda with DnaA requires the Hda residues Ser-152, Phe-118 and Asn-122 as well as Hda Arg-153 and DnaA Arg-334. Structural analyses suggest intermolecular interactions between Hda Ser-152 and DnaA Arg-334 and between Hda Phe-118 and the DnaA Walker B motif region, in addition to an intramolecular interaction between Hda Asn-122 and Arg-153. These interactions likely sustain a specific association of ADP-Hda and DnaA, promoting DnaA-ATP hydrolysis. Consistently, ATP-DnaA and ADP-DnaA interact with the ADP-Hda-DNA-clamp complex with similar affinities. Hda Phe-118 and Asn-122 are contained in the Box VI region, and their hydrophobic and electrostatic features are basically conserved in the corresponding residues of other AAA+ proteins, suggesting a conserved role for Box VI. These findings indicate novel interaction mechanisms for Hda-DnaA as well as a potentially fundamental mechanism in AAA+ protein interactions.
AB - Summary Escherichia coli ATP-DnaA initiates chromosomal replication. For preventing extra-initiations, a complex of ADP-Hda and the DNA-loaded replicase clamp promotes DnaA-ATP hydrolysis, yielding inactive ADP-DnaA. However, the Hda-DnaA interaction mode remains unclear except that the Hda Box VII Arg finger (Arg-153) and DnaA sensor II Arg-334 within each AAA+ domain are crucial for the DnaA-ATP hydrolysis. Here, we demonstrate that direct and functional interaction of ADP-Hda with DnaA requires the Hda residues Ser-152, Phe-118 and Asn-122 as well as Hda Arg-153 and DnaA Arg-334. Structural analyses suggest intermolecular interactions between Hda Ser-152 and DnaA Arg-334 and between Hda Phe-118 and the DnaA Walker B motif region, in addition to an intramolecular interaction between Hda Asn-122 and Arg-153. These interactions likely sustain a specific association of ADP-Hda and DnaA, promoting DnaA-ATP hydrolysis. Consistently, ATP-DnaA and ADP-DnaA interact with the ADP-Hda-DNA-clamp complex with similar affinities. Hda Phe-118 and Asn-122 are contained in the Box VI region, and their hydrophobic and electrostatic features are basically conserved in the corresponding residues of other AAA+ proteins, suggesting a conserved role for Box VI. These findings indicate novel interaction mechanisms for Hda-DnaA as well as a potentially fundamental mechanism in AAA+ protein interactions.
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U2 - 10.1111/j.1365-2958.2010.07074.x
DO - 10.1111/j.1365-2958.2010.07074.x
M3 - Article
C2 - 20132442
AN - SCOPUS:77951150088
VL - 76
SP - 302
EP - 317
JO - Molecular Microbiology
JF - Molecular Microbiology
SN - 0950-382X
IS - 2
ER -