Cysteine desulfurase/Molyb cofact sulfurase - B6/P5P and Cysteine Breakdown

Cysteine desulfurase an enzyme that breakdowns cysteine into alanine. The cofactor of this process is P5P. I am not sure why, but L-cysteine supplement worsens many symptoms I have like body rashes, irritability, hair loss, and acne. I am searching for other downstream processes that would explain why I am sensitive to cysteine.

In the meantime, if you are sensitive to cysteine (which can be found out by experimental supplementation), please be cautious of taking B6 and P5P.

http://www.uniprot.org/uniprot/Q9Y697

Another enzyme responsible for cysteine metabolism is molybdenum cofactor sulfurase, which results in similar conversion, from cysteine to alanine. P5P is also a cofactor for this process as well.

http://www.uniprot.org/uniprot/Q96EN8

 

@mariovitali might have some insight.

 

Hmm what do you know...i didn't have L-Cysteine to my CFS Topics Database.

I am collecting the relevant PubMed entries and i will have some results in the morning.

What i can see is that L-Cysteine matches many CFS Topics :


Note csad.csv = cysteine sulfinic acid decarboxylase

 

And cysteine desulfurase

I will try to find why

 

One guess is it increase s glutathione production, mobilizing toxins making you feel bad. Particular ly with me CFS poor liver function means toxins aren't efficiently processed so they run around and kick butt

 

Rashes, acne and irritability (increased inflammation) , and hair loss (thyroid drop) all potential fx of detox in my experience

 

Those symptoms may point to a B2 deficiency. Have you tried taking high dose B2?

Sounds logical to me: you increase Cysteine desulfurase activity by increasing your intake of L-cysteine. This requires more P5P. B2 is required to convert pyridoxine into P5P so your need for B2 will rise. Hence you induce a B2 deficiency by increasing Cysteine. And it sounds like you're already low in B2.

I'd look into B2