Methionine

Methionine, the other culprit.


While owners of cystinouric dogs are focusing their attention on Cystine as the main problem, there is a second amino-acid that is just as dangerous. Methionine is another sulfur amino-acid that exists in nearly all food just as Cystine does, but does not always stay in its original form. What does this mean ?
After consuming food, the Methionine in it can be activated and produce S-Adenosyl Methionine which in turn can produce S-Adenosyl Homocysteine which is immediately converted to Homocysteine which in turn can be converted back to Methionine or Cystine.