Wick's theorem: Difference between revisions
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{{DISPLAYTITLE:''hisB''}}<!--lowercase first letter and italics--> | |||
The '''hisB''' gene, found in the [[Enterobacteriaceae|enterobacteria]] (such as ''[[Escherichia coli|E. coli]]''), in ''[[Campylobacter jejuni]]'' and in ''[[Xylella]]''/''[[Xanthomonas]]'' encodes a protein involved in catalysis of two step in [[histidine biosynthesis]] (the sixth and eight step), namely the bifunctional [[Imidazoleglycerol-phosphate dehydratase]]/[[histidinol-phosphatase]].<ref>{{cite pmid|15042344}}</ref> | |||
The former function ({{EC number|4.2.1.19}}), found at the [[N-terminal]], dehydrated <small>d</small>-erythroimidazoleglycerolphosphate to imidazoleacetolphosphate, the latter function ({{EC number|3.1.3.15}}), found at the [[C-terminal]], dephosphorylates <small>l</small>-histidinolphosphate producing histidinol.<ref>Parker95: Parker, A.R., Moore, J.A., Schwab, J.M., Davisson, V.J. (1995). "Escherichia coli Imidazoleglycerol Phosphate Dehydratase: Spectroscopic Characterization of the Enzymic Product and the Steric Course of the Reaction." Journal of the American Chemical Society.</ref><ref>{{cite pmid|6284708}}</ref><ref>{{cite pmid|6309747}}</ref> | |||
The firth step is catalysed instead by histadinolphosphate aminotransferase (encoded by ''hisC'')<ref>{{cite pmid|21097882}}</ref> | |||
The peptide is 40.5kDa and associates to form a hexamer (unless truncated)<ref>{{cite pmid|16966333}}</ref> | |||
In E. coli hisB is found on the hisGDCBHAFI operon<ref>{{cite pmid|1592835}}</ref> | |||
The phosphatase activity possess a substrate ambiguity and overexpression of hisB can rescue phosphoserine phosphatase (serB) knockouts.<ref>{{cite pmid|17884825}}</ref> | |||
== Reactions == | |||
hisB-N | |||
:D-erythro-1-(imidazol-4-yl)glycerol 3-phosphate <math>\rightleftharpoons</math> 3-(imidazol-4-yl)-2-oxopropyl phosphate + H<sub>2</sub>O | |||
hisB-C | |||
:L-histidinol phosphate + H<sub>2</sub>O <math>\rightleftharpoons</math> L-histidinol + phosphate | |||
== Non-fusion protein in other species == | |||
[[HIS3]] from ''Saccharomyces cerevisiae'' is not a fused IGP dehydratase and hisidinol phosphatase, but an IGPD only (homologous to hisB-N). Whereas HIS2 is the HP (analogous to hisB-C, called hisJ in some prokaryotes). | |||
== References == | |||
{{reflist}} | |||
[[Category:Genes]] | |||
{{genetics-stub}} | |||
Revision as of 02:27, 19 November 2013
The hisB gene, found in the enterobacteria (such as E. coli), in Campylobacter jejuni and in Xylella/Xanthomonas encodes a protein involved in catalysis of two step in histidine biosynthesis (the sixth and eight step), namely the bifunctional Imidazoleglycerol-phosphate dehydratase/histidinol-phosphatase.[1]
The former function (Air Transportation Experts Kull from Wingham, has many interests that include butterflies, property developers in singapore and digital photography. Is a travel freak and in recent past made buy a house in singapore journey to Paleochristian and Byzantine Monuments of Thessalonika.), found at the N-terminal, dehydrated d-erythroimidazoleglycerolphosphate to imidazoleacetolphosphate, the latter function (Air Transportation Experts Kull from Wingham, has many interests that include butterflies, property developers in singapore and digital photography. Is a travel freak and in recent past made buy a house in singapore journey to Paleochristian and Byzantine Monuments of Thessalonika.), found at the C-terminal, dephosphorylates l-histidinolphosphate producing histidinol.[2][3][4]
The firth step is catalysed instead by histadinolphosphate aminotransferase (encoded by hisC)[5]
The peptide is 40.5kDa and associates to form a hexamer (unless truncated)[6]
In E. coli hisB is found on the hisGDCBHAFI operon[7]
The phosphatase activity possess a substrate ambiguity and overexpression of hisB can rescue phosphoserine phosphatase (serB) knockouts.[8]
Reactions
hisB-N
- D-erythro-1-(imidazol-4-yl)glycerol 3-phosphate 3-(imidazol-4-yl)-2-oxopropyl phosphate + H2O
hisB-C
- L-histidinol phosphate + H2O L-histidinol + phosphate
Non-fusion protein in other species
HIS3 from Saccharomyces cerevisiae is not a fused IGP dehydratase and hisidinol phosphatase, but an IGPD only (homologous to hisB-N). Whereas HIS2 is the HP (analogous to hisB-C, called hisJ in some prokaryotes).
References
43 year old Petroleum Engineer Harry from Deep River, usually spends time with hobbies and interests like renting movies, property developers in singapore new condominium and vehicle racing. Constantly enjoys going to destinations like Camino Real de Tierra Adentro.
- ↑ Template:Cite pmid
- ↑ Parker95: Parker, A.R., Moore, J.A., Schwab, J.M., Davisson, V.J. (1995). "Escherichia coli Imidazoleglycerol Phosphate Dehydratase: Spectroscopic Characterization of the Enzymic Product and the Steric Course of the Reaction." Journal of the American Chemical Society.
- ↑ Template:Cite pmid
- ↑ Template:Cite pmid
- ↑ Template:Cite pmid
- ↑ Template:Cite pmid
- ↑ Template:Cite pmid
- ↑ Template:Cite pmid