See the recent post in my blog entitled, 'Intestinal Dysbiosis and the Causes of Disease: Article by Galland and Barrie' that I hope will give you a good picture of what goes on in the gut. I hope it helps answer some of your questions. http://www.healthy.net/scr/Article.asp?Id=423
I'll keep researching some more to see if I can find more info for you.