Abstract
The x-ray crystal structure of the Escherichia coli RecA protein indicates that the phosphate groups of the nucleotide cofactor are bound by a loop whose amino acid sequence (66GPESSGKT73) corresponds to a consensus phosphate binding loop sequence (GXXXXGK[T/S]) found in many NTP-binding proteins. As part of an investigation of the role of the P-loop in ATP hydrolysis, we prepared a mutant RecA protein in which serine 69 was replaced by a glycine residue. We have found that the [S69G]RecA mutation has a differential effect on the hydrolysis of various nucleoside triphosphates. The [S69G]RecA protein catalyzes the single-stranded DNA-dependent hydrolysis of rATP, ddATP, and dATP with turnover numbers of 10, 20, and 36 min-1, respectively. The wild type RecA protein, in contrast, hydrolyzes each of these nucleoside triphosphates with similar turnover numbers of 20-24 min- 1. Significantly, the [S69G]RecA protein promotes strand exchange with all three nucleoside triphosphates, and the rate of strand exchange is directly proportional to the rate of hydrolysis of each of the nucleotide cofactors. These findings with the [S69G]RecA protein provide support for the existence of a mechanistic coupling between NTP hydrolysis and DNA strand exchange.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 25979-25982 |
| Number of pages | 4 |
| Journal | Journal of Biological Chemistry |
| Volume | 274 |
| Issue number | 37 |
| DOIs | |
| State | Published - Sep 10 1999 |
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ASJC Scopus subject areas
- Biochemistry
Cite this
Differential rates of NTP hydrolysis by the mutant [S69G]RecA protein. Evidence for a coupling of NTP turnover to DNA strand exchange. / Nayak, Sunil; Bryant, Floyd Ransom.
In: Journal of Biological Chemistry, Vol. 274, No. 37, 10.09.1999, p. 25979-25982.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Differential rates of NTP hydrolysis by the mutant [S69G]RecA protein. Evidence for a coupling of NTP turnover to DNA strand exchange
AU - Nayak, Sunil
AU - Bryant, Floyd Ransom
PY - 1999/9/10
Y1 - 1999/9/10
N2 - The x-ray crystal structure of the Escherichia coli RecA protein indicates that the phosphate groups of the nucleotide cofactor are bound by a loop whose amino acid sequence (66GPESSGKT73) corresponds to a consensus phosphate binding loop sequence (GXXXXGK[T/S]) found in many NTP-binding proteins. As part of an investigation of the role of the P-loop in ATP hydrolysis, we prepared a mutant RecA protein in which serine 69 was replaced by a glycine residue. We have found that the [S69G]RecA mutation has a differential effect on the hydrolysis of various nucleoside triphosphates. The [S69G]RecA protein catalyzes the single-stranded DNA-dependent hydrolysis of rATP, ddATP, and dATP with turnover numbers of 10, 20, and 36 min-1, respectively. The wild type RecA protein, in contrast, hydrolyzes each of these nucleoside triphosphates with similar turnover numbers of 20-24 min- 1. Significantly, the [S69G]RecA protein promotes strand exchange with all three nucleoside triphosphates, and the rate of strand exchange is directly proportional to the rate of hydrolysis of each of the nucleotide cofactors. These findings with the [S69G]RecA protein provide support for the existence of a mechanistic coupling between NTP hydrolysis and DNA strand exchange.
AB - The x-ray crystal structure of the Escherichia coli RecA protein indicates that the phosphate groups of the nucleotide cofactor are bound by a loop whose amino acid sequence (66GPESSGKT73) corresponds to a consensus phosphate binding loop sequence (GXXXXGK[T/S]) found in many NTP-binding proteins. As part of an investigation of the role of the P-loop in ATP hydrolysis, we prepared a mutant RecA protein in which serine 69 was replaced by a glycine residue. We have found that the [S69G]RecA mutation has a differential effect on the hydrolysis of various nucleoside triphosphates. The [S69G]RecA protein catalyzes the single-stranded DNA-dependent hydrolysis of rATP, ddATP, and dATP with turnover numbers of 10, 20, and 36 min-1, respectively. The wild type RecA protein, in contrast, hydrolyzes each of these nucleoside triphosphates with similar turnover numbers of 20-24 min- 1. Significantly, the [S69G]RecA protein promotes strand exchange with all three nucleoside triphosphates, and the rate of strand exchange is directly proportional to the rate of hydrolysis of each of the nucleotide cofactors. These findings with the [S69G]RecA protein provide support for the existence of a mechanistic coupling between NTP hydrolysis and DNA strand exchange.
UR - http://www.scopus.com/inward/record.url?scp=0033543753&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=0033543753&partnerID=8YFLogxK
U2 - 10.1074/jbc.274.37.25979
DO - 10.1074/jbc.274.37.25979
M3 - Article
C2 - 10473540
AN - SCOPUS:0033543753
VL - 274
SP - 25979
EP - 25982
JO - Journal of Biological Chemistry
JF - Journal of Biological Chemistry
SN - 0021-9258
IS - 37
ER -