Sandbox Reserved 1052
From Proteopedia
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== DNA Bound State == | == DNA Bound State == | ||
| - | The <scene name='69/694219/Serandhisresidues/2'>main DNA interactions</scene> have been found to occur at the Ser 54 and 57 along with His 58. These residues are likely to interact with the 5'-TGAA sequence found in the half-site of the DNA. These residues are found in the N terminal of the R helix. The residues involved in the <scene name='69/694219/Dna_binding_pocket/1'>DNA binding pocket</scene> are Val 42 and Gln 53. This was experimentally determined by replacing the Gln and Val with Ala residues and measuring the binding capacity; | + | The <scene name='69/694219/Serandhisresidues/2'>main DNA interactions</scene> have been found to occur at the Ser 54 and 57 along with His 58. These residues are likely to interact with the 5'-TGAA sequence found in the half-site of the DNA. These residues are found in the N terminal of the R helix. The residues involved in the <scene name='69/694219/Dna_binding_pocket/1'>DNA binding pocket</scene> are Val 42 and Gln 53. This was experimentally determined by replacing the Gln and Val with Ala residues and measuring the binding capacity; In a previously published article<ref name="LoC">[Arunkumar A., Campanello G., Giedroc D. (2009). Solution Structure of a |
paradigm ArsR family zinc sensor in the DNA-bound state. PNAS 106:43 | paradigm ArsR family zinc sensor in the DNA-bound state. PNAS 106:43 | ||
| - | 18177-18182.]</ref> | + | 18177-18182.]</ref>, the DNA bound state of CzrA was tested by using the known critical residues for DNA interactions. Critical residues, Gln53, Val42, Ser54, Ser57, and His58, were replaced with Ala and then compared to the kinetics of the wild type protein. Replacing only the Q53 and V42 residues resulted in an 11-fold and 160-fold decrease in K<sub>a</sub>, respectively. Other residues such as S54, S57, and H58 were also replaced with Ala residues, and it was found that these mutations caused binding similar to the fully inhibited Zn<sup>2+</sup> bound state. Table 1 in this articel show the different K<sub>observed</sub>, and the measured decrease in K<sub>observed</sub> for each mutation. |
== Zinc Ligand(s) == | == Zinc Ligand(s) == | ||
Revision as of 02:39, 27 March 2017
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Contents |
CzrA
Biological Function
Structural Overview
DNA Bound State
The have been found to occur at the Ser 54 and 57 along with His 58. These residues are likely to interact with the 5'-TGAA sequence found in the half-site of the DNA. These residues are found in the N terminal of the R helix. The residues involved in the are Val 42 and Gln 53. This was experimentally determined by replacing the Gln and Val with Ala residues and measuring the binding capacity; In a previously published article[1], the DNA bound state of CzrA was tested by using the known critical residues for DNA interactions. Critical residues, Gln53, Val42, Ser54, Ser57, and His58, were replaced with Ala and then compared to the kinetics of the wild type protein. Replacing only the Q53 and V42 residues resulted in an 11-fold and 160-fold decrease in Ka, respectively. Other residues such as S54, S57, and H58 were also replaced with Ala residues, and it was found that these mutations caused binding similar to the fully inhibited Zn2+ bound state. Table 1 in this articel show the different Kobserved, and the measured decrease in Kobserved for each mutation.
Zinc Ligand(s)
</StructureSection>
References
Arunkumar A., Campanello G., Giedroc D. (2009). Solution Structure of a paradigm ArsR family zinc sensor in the DNA-bound state. PNAS 106:43 18177-18182
Penella M., Shokes J., Cosper N., Scott R.,Giedroc D. (2002). Structural elements of metal selectivity in metal sensor proteins. PNAS 100:7 3713-3718.
