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Re: OVIRAPTOROSAURIA! Part One [Overview]

Ralph Miller III wrote:

> Yes, but perhaps actual feather keratin could be preserved, as Mary Higby
> Schweitzer has proposed for a (Cretaceous) specimen of _Shuvuuia deserti_
> found in bird feathers.  She revealed her results both at the 1997 SVP
> meeting and at the 1998 Dinofest symposium.  Quoting the Dinofest abstract
> volume:
> "Microscopic and chemical analyses eliminated plant material or fungal
> hyphae as a source for these fibers.  Antibodies specific for beta keratin
> reacted strongly with these fibers, while antibodies against alpha keratin,
> antibodies present in normal sera, and antibodies raised against a
> non-relevant protein were negative for binding, a pattern consistent with
> modern feathers."
> I hope that she publishes a paper on this work in the near future!

Does anyone recall any details from this talk?  With the usual caveat 
about my out-of-date knowledge base, I might add that it is (was?) very 
difficult to get good antibodies against keratin.  Keratin is so 
ubiquitous that any immune reaction to keratin would likely kill the 
organism producing the antibody in pretty short order.  One has to be 
very careful to show that the antiserum is reacting to keratin and not 
(a) to some protein contaminant in the antigen (keratin) prep used to 
induce the production of antibody or (b) to some component of the 
adjuvant (e.g. mineral oil) used in the antigen prep to promote the 
immune response.

These days, with monoclonal antibodies and so on, its a lot easier to get 
a clean reaction.  Still, rigorous control work is necesary.  That goes 
double when you deal with differences as fine as alpha and beta keratin. 
 These are chemically identical conformers, so a degree of cross 
contamination in the antigen is inevitable.

  --Toby White