- From: Waclaw Kusnierczyk <Waclaw.Marcin.Kusnierczyk@idi.ntnu.no>
- Date: Thu, 19 Jul 2007 22:28:35 +0200
- To: public-semweb-lifesci@w3.org
Michel_Dumontier wrote: > >> Sequence form is again a placeholder term ... > >> ... distinguish between a phosphorylated version of a >> protein and the non-phosphorylated version (as an example). The need >> for the latter derives from the fact that the two versions might have >> different functions. > > Independent of whether there is a (known) difference in function, > chemistry (and circumstance) defines function. Any chemical modification > results in a different biochemical entity with potentially different > function. Proteins and their "version" derivatives are no exception. The > relationship between them is that they participate in a chemical > process, but they are fundamentally different entities. An interesting issue, one of identity. What determines the identity of a molecule, a protein in this case? If you have a protein that becomes phosphorylated, is the phosphorylated protein another one, numerically distinct from that non-phosphorylated that was there before? (The 'becomes' is somewhat inappropriate here.) What changes can a protein undergo to still be the same protein, and what events make it to another protein? Is it completely arbitrary, i.e., is the identity dependent merely on the observer's fiat? If I remove a page from a book, is it the same book, or another book? Does "fundamentally different" imply "non-identical", or merely "discernible"? vQ
Received on Thursday, 19 July 2007 20:28:51 UTC