Charge of Tyrosine in a Protein

[TAFFETS at SNYSYRV1.bitnet]

We have recently been analyzing some results with site-directed mutations which
can be most easily explained if a tyrosine in a protein we have been analyzing
was negatively charged while the cells were at pH 7.0.  Is this possible (other
than if the tyrosine was phosphorylated) and if it is possible can anyone
suggest a reference on this?

Thanks
Steve
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Steven Taffet, Ph.D.
Associate Professor
Department of Microbiology and Immunology
S.U.N.Y. Health Science Center
750 E. Adams Avenue
Syracuse, New York 13210

Phone (315) 464-5419
FAX   (315) 464-4417
Bitnet  TAFFETS at snysyrv1
Internet TAFFETS at vax.cs.hscsyr.edu
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