Difference between revisions of "Transformation of AA to 12-HPETE"

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(Enzyme Parameters)
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===K<sub>mp</sub>===
 
===K<sub>mp</sub>===
 +
This is a “Dependent parameter”, meaning that the log-normal distribution for this parameter was calculated using multivariate distributions  (this is discussed in detail[[Quantification of parameter uncertainty | here]]). As a result, no confidence interval factor or literature values were cited for this parameter.
 
{| class="wikitable"
 
{| class="wikitable"
 
|+  style="text-align: left;" | Description of the 12-LOX Kmp distribution
 
|+  style="text-align: left;" | Description of the 12-LOX Kmp distribution

Revision as of 06:54, 16 May 2019

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LOX enzymes oxidise AA to generate hydroxy fatty acids. In the skin, the 12-LOX isoform of LOX is more active than others. This isoform is highly expressed in the resident cells of both compartments, epidermal keratinocytes and dermal fibroblasts (Dowd, Kobza Black et al. 1985). The 12- LOX enzyme catalyses the addition of O2 at the C-12 position of AA, producing 12-HPETE.

Reaction

R179AA - HPETE12.jpg

Chemical equation

 AA \rightleftharpoons 12-HPETE

Rate equation

R19.PNG

Enzyme Parameters

Kms

Literature values
Value Units Species Notes Reference
7.20E-03  mM Human Expression Vector: Platelet

Enzyme: 12-Lipoxygenase pH: 7.4 Temperature: 37°C.

[1]
8.00E-02  mM Human Expression Vector: Platelet

Enzyme: 12-Lipoxygenase pH: 7 Temperature: 24

[2]
1.00E-02  mM Human Platlet Expression Vector: Baculovirus

Enzyme: 12-Lipoxygenase pH: 8 Temperature: 37

[3]
7.90E-03 ± 8.00E-04  mM Human Expression Vector: Platelets

Enzyme:12-Lipoxygenase pH: 7.4 Temperature: 37

[4]
Description of the 12-LOX Kms distribution
Mode (mM) Confidence Interval Location parameter (σ) Scale parameter (σ)
7.60E-03 4.34E+00 -4.48E+00 6.30E-01
The estimated probability distribution for 12-LOX Kms. The value and weight of the literature values used to define the distribution are indicated by an orange dashed line. The x axis is plotted on a log-scale.

Kmp

This is a “Dependent parameter”, meaning that the log-normal distribution for this parameter was calculated using multivariate distributions (this is discussed in detail here). As a result, no confidence interval factor or literature values were cited for this parameter.

Description of the 12-LOX Kmp distribution
Mode (mM) Location parameter (µ) Scale parameter (σ)
7.30E-03 -4.52E+00 6.28E-01
The estimated probability distribution for 12-LOX Kmp. The value and weight of the literature values used to define the distribution are indicated by an orange dashed line. The x axis is plotted on a log-scale.

kcat

Literature values
Value Units Species Notes Reference
336 ± 12 per minute Human Expression Vector: Human reticulocyte

Enzyme: 15-lipoxygenase-1 pH: 7.5 Temperature: 25

[5]
504 per minute Wild Boar Expression Vector: E. coli.

Enzyme: 12-Lipoxygenase pH: 7.4 Temperature: 37

[6]
Description of the 12-LOX kcat distribution
Mode (min-1) Confidence Interval Location parameter (µ) Scale parameter (σ)
4.87E+02 1.20E+00 6.22E+00 1.80E-01
The estimated probability distribution for 12-LOX kcat. The value and weight of the literature values used to define the distribution are indicated by an orange dashed line. The x axis is plotted on a log-scale.

Enzyme concentration

12-LOX Abundance
Value Units Species Notes Reference
19.8  ppm Human Expression Vector: Spleen

Enzyme: 12-LOX pH: 7.5 Temperature: 37 °C

[7]
1.60  ppm Human Expression Vector: Liver

Enzyme: 12-LOX pH: 7.5 Temperature: 37 °C

[8]
0.28  ppm Human Expression Vector: Gut

Enzyme: 12-LOX pH: 7.5 Temperature: 37 °C

[8]
0.11  ppm Human Expression Vector: Pancreas

Enzyme: 12-LOX pH: 7.5 Temperature: 37 °C

[8]
Description of the 12-LOX concentration distribution
Mode (mM) Confidence Interval Location parameter (µ) Scale parameter (σ)
4.98E-01 7.23E+00 7.12E-01 1.19E+00
The estimated probability distribution for 12-LOX concentration. The value and weight of the literature values used to define the distribution are indicated by an orange dashed line. The x axis is plotted on a log-scale.

Keq

Literature values
Gibbs Free Energy Change Units Species Notes Reference
(-69.979996) kcal/mol Not stated Estimated

Enzyme: 12-LOX Substrate: Arachidonate Product: 12-HPETE pH: 7.3 ionic strength: 0.25

[9]
Description of the 12-LOX Keq distribution
Mode Confidence Interval Location parameter (µ) Scale parameter (σ)
2.27E+51 1.00E+01 1.19E+02 8.90E-01
The estimated probability distribution for 12-LOX Keq. The value and weight of the literature values used to define the distribution are indicated by an orange dashed line. The x axis is plotted on a log-scale.

References

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