Sandbox Reserved 1061: Difference between revisions

Line 41:

[[Image:Ribonucleotide Reduction Class 1b.jpg|thumb|center|upright=2.5|'''Figure 4.'''Ribonucleotide Reduction Class Ib general mechanism.<ref name="Makhlynets">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> The role of NrdH is highlighted.]]

[[Image:]]

== Relevance ==

Like most NrdHs, MtNrdH is similar in sequence to glutaredoxins, but structurally similar to thioredoxins (Figure 5). MtNrdH also accepts electrons from thioredoxin reductase, a characteristic of thioredoxins, but not glutaredoxins.<ref name="Swastik" /> [[Image:Image-Super imposed molecules.png|thumb|left|'''Figure 5.'''Structural comparison of NrdHs with "thioredoxin folds": ''E. Coli'' NrdH (green), ''C. ammoniagenes'' NrdH (blue), ''M. tuberculosis'' NrdH (red)<ref name="PyMol" />]]

Like most NrdHs, MtNrdH is similar in sequence to glutaredoxins, but structurally similar to thioredoxins (Figure 6). MtNrdH also accepts electrons from thioredoxin reductase, a characteristic of thioredoxins, but not glutaredoxins.<ref name="Swastik" /> [[Image:Image-Super imposed molecules.png|thumb|left|'''Figure 6.'''Structural comparison of NrdHs with "thioredoxin folds": ''E. Coli'' NrdH (green), ''C. ammoniagenes'' NrdH (blue), ''M. tuberculosis'' NrdH (red)<ref name="PyMol" />]]

Similar structures of NrdH have been isolated in other primitive species including ''E. coli'', ''S. pyogenes'', ''S. typhimurium'', ''D. deserti'', ''S. flexneri 2457T'', ''S. dysenteriae'', and ''C. glutamicium''<ref>Wang, M. et al. Mol Cell Proteomics 2012, doi:10.1074/mcp.O111.014704. http://pax-db.org/#!search?q=NrdH%250A</ref> <ref>Si, M.-R., Zhang, L., Yang, Z.-F., Xu, Y.-X., Liu, Y.-B., Jiang, C.-Y., … Liu, S.-J. (2014). NrdH Redoxin Enhances Resistance to Multiple Oxidative Stresses by Acting as a Peroxidase Cofactor in Corynebacterium glutamicum. Applied and Environmental Microbiology, 80(5), 1750–1762. doi:10.1128/AEM.03654-13</ref> In higher order multi-cellular organisms, however the NrdH protein is replaced by more complex glutaredoxins or thioredoxins. This observation leads some to speculate that NrdH is one of the very first ancestors in the ribonucleotide reduction pathway. <ref name="Swastik" /> If this is true, NrdH can be seen as a critical protein that allowed for the development of DNA-based life since deoxyribonucleotides could not have existed without the ribonucleotide reduction pathway. A better understanding of the evolutionary timeline of NrdH and similar proteins could shed greater light onto the [http://en.wikipedia.org/wiki/RNA_world RNA Wold Hypothesis], specifically describing the time frame of emergence of DNA based life.

Sandbox Reserved 1061: Difference between revisions

Navigation menu

Page actions

Page actions

Personal tools

Navigation

Search

Tools

@@ Line 41: / Line 41: @@
 [[Image:Ribonucleotide Reduction Class 1b.jpg|thumb|center|upright=2.5|'''Figure 4.'''Ribonucleotide Reduction Class Ib general mechanism.<ref name="Makhlynets">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> The role of NrdH is highlighted.]]
+[[Image:]]
 == Relevance ==
-Like most NrdHs, MtNrdH is similar in sequence to glutaredoxins, but structurally similar to thioredoxins (Figure 5). MtNrdH also accepts electrons from thioredoxin reductase, a characteristic of thioredoxins, but not glutaredoxins.<ref name="Swastik" />  [[Image:Image-Super imposed molecules.png|thumb|left|'''Figure 5.'''Structural comparison of NrdHs with "thioredoxin folds": ''E. Coli'' NrdH (green), ''C. ammoniagenes'' NrdH (blue), ''M. tuberculosis'' NrdH (red)<ref name="PyMol" />]]
+Like most NrdHs, MtNrdH is similar in sequence to glutaredoxins, but structurally similar to thioredoxins (Figure 6). MtNrdH also accepts electrons from thioredoxin reductase, a characteristic of thioredoxins, but not glutaredoxins.<ref name="Swastik" />  [[Image:Image-Super imposed molecules.png|thumb|left|'''Figure 6.'''Structural comparison of NrdHs with "thioredoxin folds": ''E. Coli'' NrdH (green), ''C. ammoniagenes'' NrdH (blue), ''M. tuberculosis'' NrdH (red)<ref name="PyMol" />]]
 Similar structures of NrdH have been isolated in other primitive species including ''E. coli'', ''S. pyogenes'', ''S. typhimurium'', ''D. deserti'', ''S. flexneri 2457T'', ''S. dysenteriae'', and ''C. glutamicium''<ref>Wang, M. et al. Mol Cell Proteomics 2012, doi:10.1074/mcp.O111.014704. http://pax-db.org/#!search?q=NrdH%250A</ref> <ref>Si, M.-R., Zhang, L., Yang, Z.-F., Xu, Y.-X., Liu, Y.-B., Jiang, C.-Y., … Liu, S.-J. (2014). NrdH Redoxin Enhances Resistance to Multiple Oxidative Stresses by Acting as a Peroxidase Cofactor in Corynebacterium glutamicum. Applied and Environmental Microbiology, 80(5), 1750–1762. doi:10.1128/AEM.03654-13</ref> In higher order multi-cellular organisms, however the NrdH protein is replaced by more complex glutaredoxins or thioredoxins. This observation leads some to speculate that NrdH is one of the very first ancestors in the ribonucleotide reduction pathway. <ref name="Swastik" /> If this is true, NrdH can be seen as a critical protein that allowed for the development of DNA-based life since deoxyribonucleotides could not have existed without the ribonucleotide reduction pathway. A better understanding of the evolutionary timeline of NrdH and similar proteins could shed greater light onto the [http://en.wikipedia.org/wiki/RNA_world RNA Wold Hypothesis], specifically describing the time frame of emergence of DNA based life.