- From: Wacek Kusnierczyk <Waclaw.Marcin.Kusnierczyk@idi.ntnu.no>
- Date: Thu, 26 Mar 2009 16:59:20 +0100
- To: Phillip Lord <phillip.lord@newcastle.ac.uk>
- CC: W3C HCLSIG hcls <public-semweb-lifesci@w3.org>
Phillip Lord wrote: > Wacek Kusnierczyk <Waclaw.Marcin.Kusnierczyk@idi.ntnu.no> writes: > >>>> I don't know whether the BioPAX Level 2 definition of protein is the >>>> most useful one, but at least it sounds clear to me: >>>> >>>> protein = anything containing exactly one polypeptide chain >>>> >>>> Clear enough? >>>> >>>> >>> So insulin is not a protein, wheras a dipeptide is? >>> >>> >> indeed; insulin is a protein complex, and a dipeptide, following this >> and other similar definitions, is a protein. >> >> > > Insulin is two polypeptide changes so following this definition is not a > protein. > that's what i was saying: that it is a protein complex, specifically, an aggregate of two polypeptide chains. it may sound revolutionary to you that insulin is not a protein, since insulin is typically called a 'protein'. but, provided one accepts a definition like the one above, there is nothing wrong in saying that insulin is not a protein. i didn't say i supported the definition from biopax, though. the one i found in stryer's biochemistry seemed to concord with it (modulo the somewhat unfortunate 'contains'), but i don't think those authors would insist that insulin is not a protein, and that any dipeptide is a protein; biopaxers seem to do that. i agree, of course, that insisting on definitions that are counterintuitive to what experts in the field are used to think is not a good idea. vQ
Received on Thursday, 26 March 2009 16:00:10 UTC