Is MeHgCysteine the correct amino acid?

No.12036408 ViewReplyOriginalReport
1. Organisms willingly accumulate MeHgCysteine.
2. Methionine is weird - it's supposedly essential, yet its restriction increases lifespan.

Is there any possibility that MeHgCysteine is actually the correct essential amino acid, and the body confuses methionine for it and not the reverse?