Homochirality question

My thoughts on why we're all made of L-amino acids and D-sugars is that it was "luck" - the very early almost-life forms with L-amino acids got a small head start and "ate" the D-forms. Polypeptides (chains of amino acids) with both chiralities would be much more disordered - by which I mean only that they would have a much tougher time forming the neat little coils and pleats we see in homochiral proteins - and would probably lose out in any self-catalytic games that would lead to more of themselves.If I muster the energy, I'll try to go look up how sugars and amino acids are biosynthesized wrt their handedness. I'll bet a nickel that sugars are D because amino acids are L, or perhaps vice versa.Added by edit:
Hello, New Person! We're glad you delurked!This message has been edited by Coragyps, 04-16-2005 06:46 PM

I understood it but didn't answer too clearly. I'm guessing here, but perhaps early life or proto-life was non-specific enough in its reactions that it was able to assimilate D-amino acids or L-sugars for their carbon and nitrogen - catabolizing them for raw materials instead of racemizing or using them directly. I don't know what modern life forms do with wrong-handed nutrients, asides from an old science fiction story where a guy got "wormholed" into his mirror-image and slowly starved.....And the more I think on it, the more sure I am that D-sugars are a direct consequence of L-aa's getting an upper hand early on. My biochem was too far in the past and too sketchy to say just how.