Xref: utzoo sci.bio:4932 bionet.molbio.proteins:159 Path: utzoo!utgpu!news-server.csri.toronto.edu!rpi!zaphod.mps.ohio-state.edu!sdd.hp.com!swrinde!elroy.jpl.nasa.gov!decwrl!pa.dec.com!hollie.rdg.dec.com!psw.enet.dec.com!winalski From: winalski@psw.enet.dec.com (Paul S. Winalski) Newsgroups: sci.bio,bionet.molbio.proteins Subject: Re: post translational modification: DOPA? Keywords: DOPA Message-ID: <1991May2.181551.1479@hollie.rdg.dec.com> Date: 2 May 91 18:15:51 GMT References: Sender: news@hollie.rdg.dec.com (Mr News) Reply-To: winalski@psw.enet.dec.com (Paul S. Winalski) Organization: Digital Equipment Corporation Lines: 31 In article , eesnyder@boulder.Colorado.EDU (Eric E. Snyder) writes: |> |>I heard an interesting talk last night... just in passing, |>the speaker mentioned an invertebrate protein containing |>17% dihydroxyphenylalanine (aka DOPA)! I couldn't believe |>this... |> |>Have I been living under a rock for the last 25 yrs? |> I guess so. My early-1970s edition of Lehninger's Biochemistry text discusses this sort of thing. |>How common is this protein modification? |> Exotic amino acids seem to be quite common in structural proteins, such as chitin in arthropods and collagen and elastin in vertebrates. |>Is it post-translational? |> Yes. The amino acid residues are normal phenylalanine after translation. The modification to DOPA occurs by enzymatic modification of the residues after the protein is transcribed. |>Does it occur in vertebrates? |> I don't know about this particular case, but the general process (enzymatic formation of exotic amino acids from normal amino acids after translation) does occur in vertebrates. --PSW