User:Jonathan Cline/Notebook/Melaminometer/Technical Summary: Difference between revisions
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== Metabolic Pathway == | |||
<pre> | <pre> | ||
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</pre> | </pre> | ||
== Detection Threshold == | |||
From the U.S. FDA standards, | |||
* a level of melamine and its analogues above 2.5 mg/kg is indicative of food adulteration. | |||
* This 2.5 ppm represents consumption of 0.063 mg/kg bw/d. | |||
The threshold needed for detection is (x mMol) or no greater than 2.5 ppm. | |||
== Logical operation == | |||
Desired logical operation: | Desired logical operation: | ||
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<pre> | <pre> | ||
if [ melamine | if [ melamine plus cyanuric acid > threshold ] | ||
then | then | ||
amplify | amplify | ||
express | express RFP ; or other reporter | ||
stop | stop | ||
else | else | ||
repress | repress RFP ; or other reporter | ||
stop | stop | ||
endif | endif | ||
</pre> | </pre> | ||
Latest revision as of 04:21, 16 October 2008
Technical Summary of Melamine Detector
Melamine can be metabolized by biochemical/enzymatic process in bacteria and/or other compatible organisms. Using recombinant DNA techniques, plasmids containing genes encoding specific enzymes will be used to modify the target organism (aka: the chassis). There may be one to four enzymes required for metabolism to desired products.
Metabolic Pathway
melamine --(1)--> ammeline --(2)--> ammelide --(3)--> cyanuric acid cyanuric acid --(4)--> biuret --(5)--> allophante --(6)--> 2 NH3 + some CO2 * (1): melamine deaminase:triA --^ NH4+ + H2O * (2): ammeline aminohydralase:triA --^ NH4+ + H2O * (3): ammelide aminohydralase:trzC --^ NH4+ + H2O * (4): atzD/trzD --^ NH4+ + H2O * (5): atzE * (6): atzF
Detection Threshold
From the U.S. FDA standards,
- a level of melamine and its analogues above 2.5 mg/kg is indicative of food adulteration.
- This 2.5 ppm represents consumption of 0.063 mg/kg bw/d.
The threshold needed for detection is (x mMol) or no greater than 2.5 ppm.
Logical operation
Desired logical operation:
if [ melamine plus cyanuric acid > threshold ] then amplify express RFP ; or other reporter stop else repress RFP ; or other reporter stop endif
