From: danj@merlot.gwu.edu (Dan Jacobson )
Subject: Re: tryp in IgG ?
Organization: George Washington University, Washington, D.C.
Date: Tue, 17 Nov 1992 16:56:46 GMT

In article <1992Nov16.162558.20257@crd.ge.com> ebstokes@maxwell.crd.ge.com (Ed Stokes) writes:
>I am a physicist investigating the binding and optical properties
>of antibodies for possible sensor applications. My understanding
>is that if an IgG antibody contains tryptophan in the binding
>pocket, then the perturbation of the tryptophan luminescence
>properties can be used to identify an antigen binding event.
>
>Are the sequences of IgG's from various species and for various
>antigens known ? How can I know whether there are luminescent
>amino acid residues in the binding pocket of a particular
>antibody ? Can these properties be engineered ?
>
>Thanks
>Ed Stokes
>ebstokes@crd.ge.com


Umm - first off I think you're talking about fluorescence -

the emission of or the property of emission of or the property of
emitting electromagnetic radiation usu. as visible light resulting from
and only during the absorption of radiation from some other source

rather than luminescence - 

an emission of light that is not
ascribable directly to incandescence and therefore occurs at low
temperatures and that is produced by physiological processes (as in the
firefly), by chemical action, by friction, or by electrical action.

With that minor clarification aside - yes the sequences for some species
and some antigens are known.  As a starting point I suggest that you
take a look at the sequences that are in the databases - a quick search
of Genbank for IgG yeilds the following list. Note that many of these
sequences are IgG RECEPTORS etc.. not IgG itself.


      1.  IIMSG1 IgG1 induction factor precursor - Mouse.
      2.  QVSAA Protein A precursor - Staphylococcus aureus.
      3.  A24496 IgG-binding protein - Streptococcus sp. (group G).
      4.  A26314 Protein G - Streptococcus sp. (fragment).
      5.  A26555 Ig heavy chain V region (Ger) - Human (fragment).
      6.  B25521 Ig kappa chain precursor V region (305) - Human.
      7.  A25521 Ig kappa chain V region (321) - Human (fragment).
      8.  B26555 Ig kappa chain V-III region (Ger) - Human.
      9.  S03018 IgG Fc receptor (clone p135) - Human.
      10. S03019 IgG Fc receptor (clone p98/X2) - Human.
      11. A31932 IgG Fc receptor precursor - Human.
      12. JU0284 IgG Fc receptor precursor, type III-1.
      13. JL0107 IgG Fc receptor precursor, type III-2 (NK cells) -.
      14. JH0429 IgG light chain V region VKIIIb-T14 - Human.
      15. S00477 Surface glycoprotein CDw32 precursor (clone PC23) -.
      16. S00478 Surface glycoprotein CDw32 precursor (clone TC3) -.
      17. S02297 Surface glycoprotein CDw32 precursor - Human.
      18. PT0356 IgG kappa chain V region 2B11.1 - Mouse (fragment).
      19. PT0358 IgG kappa chain V region 7D2.G12 - Mouse (fragment).
      20. PT0357 IgG kappa chain V region C8.5 - Mouse (fragment).
      21. PT0359 IgG kappa chain V region R4A.12 - Mouse (fragment).
      22. A35902 Fc gamma (IgG) receptor II (low affinity) alpha.
      23. S02117 IgG Fc receptor 51K chain precursor - Rat.
      24. A33939 *IgG Fc receptor II precursor - Streptococcus sp..
      25. A39041 *IgG-binding protein - Streptococcus sp. (group G).
      26. S20760 *IgG heavy chain (5.7S ) - Duck.
      27. S20759 *IgG heavy chain (7.8S) - Duck.
      28. A39878 *CD64 (high affinity IgG receptor) precursor - Human.
      29. B41357 *Fc-gamma (IgG) receptor I (high affinity) - Human.
      30. A41357 *Fc-gamma (IgG) receptor I (high affinity) form b -.
      31. S06946 *IgG Fc receptor - Human.
      32. JL0118 *IgG Fc receptor IIa (CD32) precursor - Human.
      33. A32933 *IgG receptor CD16 (clone HL12) - Human (fragment).
      34. S13852 *CD4-IgG - Chinese hamster.
      35. A40071 *Fc gamma (IgG) receptor II (low affinity) beta-1.
      36. B40071 *Fc gamma (IgG) receptor II (low affinity) beta-2.
      37. A35944 *IgG heavy chain 2a - Mouse (fragment).



Best of luck,


Dan Jacobson

danj@chablis.gwu.edu