What is the difference between D-Methionine and DL-methionine?

Answer 1

Methionine is a critical amino acid in the production of creatine.

Creatine

plays second string to the needs such as carnitine

for the heart muscles. DL-methionine

in the right mixture creates sort of starvation. Nothing is left for creatine

production but the D-isomer,

eating more introduces more D-isomer

into the equation.

L-methionine

is the only assimilable isomer that does not require an unnatural conversion, over

excretion, or, execrative

metabolism. D-methionine

(see related link) may become involved preliminarily in some simple metabolic processes. It may be integrated accidentally into proteins, in effect denaturing those proteins to varying degrees. Exactly how D-methionine

is handled by mammalian systems is not of scientific importance because naturally it would never happen.

Answer 2

D-Methionine is the naturally occurring form of methionine, while DL-methionine is a synthetic mixture of both D-methionine and L-methionine. D-Methionine is typically more biologically active and ideal for supplementation in animal feed, while DL-methionine provides a cost-effective alternative but contains a mixture of stereoisomers with potentially different biological activities.