Sandbox Reserved 1061: Difference between revisions

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MtNrdH has been identified as an electron carrier protein in ribonuleotide reduction. Ribonucleotide reduction uses an enzyme called ribonucleotide reductase (RNR) to make deoxyribonucleotides, which act as precursors to DNA synthesis. Three classes of RNRs have been identified; each class differs in cofactor requirement, structure, and oxygen dependence, but the general catalytic mechanism is conserved in all three classes. Mycobacterium tuberculosis uses class I ribonucleotide reductase.

Class I RNR is further subdivided into class Ia and Ib. Both Ia and Ib reduce ribonucleotide 5’ diphosphate to deoxyribonucleotide 5’ diphosphate (NDP  dNDP). After ribonucleotide reductase performs the first round of reduction, RNR must be reduced again to reset the cycle. In class Ib, RNR is reduced by either glutadoxin or thiordoxin, which are first reduced by glutadoxin reductase and thiordoxin reductase, respectively. In class Ib, RNR is reduced by NrdE, which is first reduced by NrdH. An important distinction between Ia and Ib is that Ia is present in eukaryotes, eubacteria, bacteriophages, and virus, but Ib is only present in eubacteria.

Class I RNR is further subdivided into class Ia and Ib. Both Ia and Ib reduce ribonucleotide 5’ diphosphate to deoxyribonucleotide 5’ diphosphate (NDP to dNDP). After ribonucleotide reductase performs the first round of reduction, RNR must be reduced again to reset the cycle. In class Ib, RNR is reduced by either glutadoxin or thiordoxin, which are first reduced by glutadoxin reductase and thiordoxin reductase, respectively. In class Ib, RNR is reduced by NrdE, which is first reduced by NrdH. An important distinction between Ia and Ib is that Ia is present in eukaryotes, eubacteria, bacteriophages, and virus, but Ib is only present in eubacteria.

[[Image:Ribonucleotide Reduction Class 1b.jpg|thumb|]]

<ref>Makhlynets, O., Boal, A. K., Rhodes, D. V., Kitten, T., Rosenzweig, A. C., & Stubbe, J. (2014). Streptococcus sanguinis Class Ib Ribonucleotide Reductase: HIGH ACTIVITY WITH BOTH IRON AND MANGANESE COFACTORS AND STRUCTURAL INSIGHTS. The Journal of Biological Chemistry, 289(9), 6259–6272. doi:10.1074/jbc.M113.533554.</ref>

[[Image:Ribonucleotide Reduction Class 1b.jpg|thumb|center|upright=2.0|Ribonucleotide Reduction Class Ib general mechanism. The role of NrdH is highlighted.]]

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</StructureSection>

== References ==

~~<references/>~~

Sandbox Reserved 1061: Difference between revisions

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@@ Line 16: / Line 16: @@
 MtNrdH has been identified as an electron carrier protein in ribonuleotide reduction. Ribonucleotide reduction uses an enzyme called ribonucleotide reductase (RNR) to make deoxyribonucleotides, which act as precursors to DNA synthesis. Three classes of RNRs have been identified; each class differs in cofactor requirement, structure, and oxygen dependence, but the general catalytic mechanism is conserved in all three classes. Mycobacterium tuberculosis uses class I ribonucleotide reductase.
-Class I RNR is further subdivided into class Ia and Ib. Both Ia and Ib reduce ribonucleotide 5’ diphosphate to deoxyribonucleotide 5’ diphosphate (NDP  dNDP). After ribonucleotide reductase performs the first round of reduction, RNR must be reduced again to reset the cycle. In class Ib, RNR is reduced by either glutadoxin or thiordoxin, which are first reduced by glutadoxin reductase and thiordoxin reductase, respectively. In class Ib, RNR is reduced by NrdE, which is first reduced by NrdH. An important distinction between Ia and Ib is that Ia is present in eukaryotes, eubacteria, bacteriophages, and virus, but Ib is only present in eubacteria.
+Class I RNR is further subdivided into class Ia and Ib. Both Ia and Ib reduce ribonucleotide 5’ diphosphate to deoxyribonucleotide 5’ diphosphate (NDP to dNDP). After ribonucleotide reductase performs the first round of reduction, RNR must be reduced again to reset the cycle. In class Ib, RNR is reduced by either glutadoxin or thiordoxin, which are first reduced by glutadoxin reductase and thiordoxin reductase, respectively. In class Ib, RNR is reduced by NrdE, which is first reduced by NrdH. An important distinction between Ia and Ib is that Ia is present in eukaryotes, eubacteria, bacteriophages, and virus, but Ib is only present in eubacteria.
-[[Image:Ribonucleotide Reduction Class 1b.jpg|thumb|]]
+<ref>Makhlynets, O., Boal, A. K., Rhodes, D. V., Kitten, T., Rosenzweig, A. C., & Stubbe, J. (2014). Streptococcus sanguinis Class Ib Ribonucleotide Reductase: HIGH ACTIVITY WITH BOTH IRON AND MANGANESE COFACTORS AND STRUCTURAL INSIGHTS. The Journal of Biological Chemistry, 289(9), 6259–6272. doi:10.1074/jbc.M113.533554.</ref>
+[[Image:Ribonucleotide Reduction Class 1b.jpg|thumb|center|upright=2.0|Ribonucleotide Reduction Class Ib general mechanism. The role of NrdH is highlighted.]]
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 </StructureSection>
 == References ==
-<references/>
+{{reflist}}