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Title: Implications of Structures of Synaptic Tetramers of gamma delta Resolvase for the Mechanism of Recombination

Abstract

The structures of two mutants of the site-specific recombinase, {gamma}{delta} resolvase, that form activated tetramers have been determined. One, at 3.5-Angstroms resolution, forms a synaptic intermediate of resolvase that is covalently linked to two cleaved DNAs, whereas the other is of an unliganded structure determined at 2.1-Angstroms resolution. Comparisons of the four known tetrameric resolvase structures show that the subunits interact through the formation of a common core of four helices. The N-terminal halves of these helices superimpose well on each other, whereas the orientations of their C termini are more variable. The catalytic domains of resolvase in the unliganded structure are arranged asymmetrically, demonstrating that their positions can move substantially while preserving the four-helix core that forms the tetramer. These results suggest that the precleavage synaptic tetramer of {gamma}{delta} resolvase, whose structure is not known, may be formed by a similar four-helix core, but differ in the relative orientations of its catalytic and DNA-binding domains.

Authors:
; ; ; ; ; ; ;
Publication Date:
Research Org.:
Brookhaven National Laboratory (BNL) National Synchrotron Light Source
Sponsoring Org.:
Doe - Office Of Science
OSTI Identifier:
914138
Report Number(s):
BNL-78706-2007-JA
Journal ID: ISSN 0027-8424; PNASA6; TRN: US0801568
DOE Contract Number:
DE-AC02-98CH10886
Resource Type:
Journal Article
Resource Relation:
Journal Name: Proc Natl Acad Sci USA; Journal Volume: 103; Journal Issue: 28
Country of Publication:
United States
Language:
English
Subject:
43 PARTICLE ACCELERATORS; MUTANTS; RECOMBINATION; RESOLUTION; NSLS; national synchrotron light source

Citation Formats

Kamtekar,S., Ho, R., Cocco, M., Li, W., Wenwieser, S., Boocock, M., Grindley, N., and Steitz, T. Implications of Structures of Synaptic Tetramers of gamma delta Resolvase for the Mechanism of Recombination. United States: N. p., 2006. Web. doi:10.1073/pnas.0604062103.
Kamtekar,S., Ho, R., Cocco, M., Li, W., Wenwieser, S., Boocock, M., Grindley, N., & Steitz, T. Implications of Structures of Synaptic Tetramers of gamma delta Resolvase for the Mechanism of Recombination. United States. doi:10.1073/pnas.0604062103.
Kamtekar,S., Ho, R., Cocco, M., Li, W., Wenwieser, S., Boocock, M., Grindley, N., and Steitz, T. Sun . "Implications of Structures of Synaptic Tetramers of gamma delta Resolvase for the Mechanism of Recombination". United States. doi:10.1073/pnas.0604062103.
@article{osti_914138,
title = {Implications of Structures of Synaptic Tetramers of gamma delta Resolvase for the Mechanism of Recombination},
author = {Kamtekar,S. and Ho, R. and Cocco, M. and Li, W. and Wenwieser, S. and Boocock, M. and Grindley, N. and Steitz, T.},
abstractNote = {The structures of two mutants of the site-specific recombinase, {gamma}{delta} resolvase, that form activated tetramers have been determined. One, at 3.5-Angstroms resolution, forms a synaptic intermediate of resolvase that is covalently linked to two cleaved DNAs, whereas the other is of an unliganded structure determined at 2.1-Angstroms resolution. Comparisons of the four known tetrameric resolvase structures show that the subunits interact through the formation of a common core of four helices. The N-terminal halves of these helices superimpose well on each other, whereas the orientations of their C termini are more variable. The catalytic domains of resolvase in the unliganded structure are arranged asymmetrically, demonstrating that their positions can move substantially while preserving the four-helix core that forms the tetramer. These results suggest that the precleavage synaptic tetramer of {gamma}{delta} resolvase, whose structure is not known, may be formed by a similar four-helix core, but differ in the relative orientations of its catalytic and DNA-binding domains.},
doi = {10.1073/pnas.0604062103},
journal = {Proc Natl Acad Sci USA},
number = 28,
volume = 103,
place = {United States},
year = {Sun Jan 01 00:00:00 EST 2006},
month = {Sun Jan 01 00:00:00 EST 2006}
}
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  • Abstract not provided.