There are review articles on various motifs. I think that I remember that you can also find motifs via sequence or structure classes on places like SWISSPROT/EXPASY. A quick search of PUBMED did not produce a single-source paper listing the various motifs...and there are several. Biochemistry texts will list a few motifs but will be far from exhaustive.
Adding Zinc acetate to your fermentation and being careful not to use EDTA/EGTA in the prep may give you a more definitive answer. Similarly, DTT and TCEP can be good chelators of metals, so I would avoid those. Your initial comment indicated that you had no diffraction yet. Does that mean you have crystals??? If so, what percent of your produced protein is the putative zinc finger region? If it is high, and you already have crystals, then you may be searching for a problem that does not exist. -- James Kiefer, Ph.D. Structural Biology Genentech, Inc. 1 DNA Way, Mailstop 27 South San Francisco, CA 94080-4990
