[John Locke]

No direct reference, but if you check upon the Lactobacilli you'll find that some of them can metabolize both L and D enantiomers. So it's possible.

For example, I believe Lactobacillus fermenti can catalyze the conversion of either enantiomer of glutamic acid into the other. That's pretty imprssive - almost the biological equivalent of catalyzing the conversion of matter to antimatter!

[furball4paws]

You are incredibly ignorant in Microbiology. Perhaps an Inro. to Microbiology course would do you good.