TY - JOUR
T1 - Structure of a complex between E. coli DNA topoisomerase I and single-stranded DNA
AU - Perry, Kay
AU - Mondragón, Alfonso
N1 - Funding Information:
We thank A. Changela and B. Taneja for their comments and suggestions. Research was supported by NIH Grant GM51350. Support from the R.H. Lurie Cancer Center of Northwestern University to the Structural Biology Facility is acknowledged. Portions of this work were performed at the DuPont-Northwestern-Dow collaborative Access Team (DND-CAT) Synchrotron Research Center at the Advanced Photon Source (APS) and at the Stanford Synchrotron Radiation Laboratory (SSRL). DND-CAT is supported by DuPont, Dow, and the NSF, and use of the APS is supported by the DOE. SSRL is operated by the DOE, Office of Basic Energy Sciences. The SSRL Biotechnology Program is supported by the NIH and the DOE.
PY - 2003/11
Y1 - 2003/11
N2 - In order to gain insights into the mechanism of ssDNA binding and recognition by Escherichia coli DNA topoisomerase I, the structure of the 67 kDa N-terminal fragment of topoisomerase I was solved in complex with ssDNA. The structure reveals a new conformational stage in the multistep catalytic cycle of type IA topoisomerases. In the structure, the ssDNA binding groove leading to the active site is occupied, but the active site is not fully formed. Large conformational changes are not seen; instead, a single helix parallel to the ssDNA binding groove shifts to clamp the ssDNA. The structure helps clarify the temporal sequence of conformational events, starting from an initial empty enzyme and proceeding to a ssDNA-occupied and catalytically competent active site.
AB - In order to gain insights into the mechanism of ssDNA binding and recognition by Escherichia coli DNA topoisomerase I, the structure of the 67 kDa N-terminal fragment of topoisomerase I was solved in complex with ssDNA. The structure reveals a new conformational stage in the multistep catalytic cycle of type IA topoisomerases. In the structure, the ssDNA binding groove leading to the active site is occupied, but the active site is not fully formed. Large conformational changes are not seen; instead, a single helix parallel to the ssDNA binding groove shifts to clamp the ssDNA. The structure helps clarify the temporal sequence of conformational events, starting from an initial empty enzyme and proceeding to a ssDNA-occupied and catalytically competent active site.
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U2 - 10.1016/j.str.2003.09.013
DO - 10.1016/j.str.2003.09.013
M3 - Article
C2 - 14604525
AN - SCOPUS:0242710959
SN - 0969-2126
VL - 11
SP - 1349
EP - 1358
JO - Structure
JF - Structure
IS - 11
ER -