Difference between revisions of "Transformation of PGH2 to PGE2"

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==Chemical equation==
 
==Chemical equation==
  
<center><math> FA \rightleftharpoons AA </math></center>
+
<center><math> PGH2 \rightleftharpoons PGE2 </math></center>
  
 
== Rate equation ==
 
== Rate equation ==
 
+
[[File:R10.PNG|center|500px]]
  
 
== PGES Enzyme Parameters ==
 
== PGES Enzyme Parameters ==

Revision as of 15:49, 25 September 2017

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PGE2 is an incredibly bioactive compound, which upon binding with the receptors, an immune cellular response is triggered. For example in the binding of PGE2 to EP2 and EP4, dendritic cell (DC) migration and maturation is activated (Legler, Krause et al. 2006, van Helden, Krooshoop et al. 2006). This event results in the activation of Th2 cells, which produce cytokines that in turn stimulates further inflammatory species (McIlroy, Caron et al. 2006, Theiner, Gessner et al. 2006). Furthermore binding of PGE2 to EP4 stimulates infiltration of macrophages from the bloodstream.

PGE2 is synthesised from PGH2 via the prostaglandin E synthase (PGES) enzyme. This influential species is produced by almost all cutaneous cell types and as a consequence is in high concentrations in the skin (Ziboh 1992, Cho, Park et al. 2005, Gledhill, Rhodes et al. 2010). In addition to affecting DCs, the species acts as a chemoattractant for keratinocyte cells (Parekh, Sandulache et al. 2009) and in normal and inflamed epithelial cells PGE2 possess an inhibitory effect on the release of leukotrienes (Shaf96).


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R10 PGH2 - PGE2.jpg

Chemical equation

 PGH2 \rightleftharpoons PGE2

Rate equation

R10.PNG

PGES Enzyme Parameters

Michaelis-Menten Constants
Value Units Species Notes Reference
1.6E-01 ± 4.00E-03  mM Human Expression Vector: E. Coli

Enzyme: PGES pH: 8 Temperature: 37

[1]
2.15E-01  mM Human Wild Type Enzyme [2]
1.49E-02  mM Human Expression Vector: E. Coli

Enzyme: PGES pH: Unknown Temperature: Unknown

Other: cPGES, casein kinase II and Hsp90

[3]
6.66E-02  mM Human Expression Vector: E. Coli

Enzyme: PGES pH: Unknown Temperature: Unknown

[3]
Enzyme Turnover Numbers
Value Units Species Notes Reference
3000 ± 360 per minute Human Expression Vector: E. Coli.

Enzyme: Microsomal Prostaglandin E Synthase pH: 7.5 Temperature: 37

[4]
PGES Abundance
Value Units Species Notes Reference
220  ppm Human Expression Vector: Placenta

Enzyme: PGES pH: 7.5 Temperature: 37 °C

[5]
75.3  ppm Human Expression Vector: Urinary Bladder

Enzyme: PGES pH: 7.5 Temperature: 37 °C

[6]
208  ppm Human Expression Vector: Stomach

Enzyme: PGES pH: 7.5 Temperature: 37 °C

[5]
28.1  ppm Human Expression Vector: Lung

Enzyme: PGES pH: 7.5 Temperature: 37 °C

[6]
11.6  ppm Human Expression Vector: Colon

Enzyme: PGES pH: 7.5 Temperature: 37 °C

[6]
Gibbs Free Energy Change
Value Units Species Notes Reference
5.72 kcal/mol Not stated Estimated

Enzyme: PGES Substrate: Arachidonate Product: PGE2 pH: 7.3 ionic strength: 0.25

[7]

References


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