> >my friend concludes that the acid actually breaks down the protein,
> ...
> >I, however, claim that the primary role of this acid is a defence
mechanism
> >against, er, antigens?
>> >Who would be the victor is such an argument? :>
>> Neither of you. Or, if you prefer, both. While it's true that acid
> contributes to the breakdown of proteins and to the defense against
> microorganisms, pepsin also contributes to the initial proteolysis; it
> breaks proteins down into smaller polypeptides and some amino acids,
> though for the most part its action isn't sufficient to completely digest
> proteins. The same goes for acid, but probably more so. (It's hard to
> say what a "primary" role of something biological is: since it wasn't
> designed, it can't have been designed for something, if you see what I
> mean.)
>> I don't know of any condition in which pepsin alone is not produced (there
> probably is one, but I don't know of it), so I can't say how important
> pepsin alone is.
Hmm, but the argument that my friend proposed is,
that enzymes, as catalysts, cannot break down material themselves,
but require another chemical, such as acid, to complete the job...
I could not demonstrate that pepsin would be able to complete its process
w/o acid,
since it require an acidic environment to work,
So the question is, not does acid contribute to the breakdown of protein,
but is it the ONLY ingredient that does this,
or do enzymes do the actual process w/o the "help" of acid...
