Advices needed

[USA::AMH12478]

References for protein crystallization:

Crystallization Of Nucleic acids & Proteins--A Practical Approach
by A. Ducruix & R. Giege

Preparation & Analysis of Protein Crystals by Alex McPherson

Methods:  A Companion to Methods in Enzymology EDs. in Chief J.N. Abelson &
M.I. Simon----------Volume 1, No. 1 August 1990---Protein & Nucleic Acid
Crystallization, Editor Charles W. Carter, Jr.

Crystallization of Membrane Proteins  ED. Hartmut Michel  CRC Press

Reference for screening method==J. Appl. Crys. (1991) 24: 409-411.  Sparse
matrix sampling:  a screening method for crystallization of proteins.

Refs. are available through Hampton Res. 800/452-3899 USA

Whenever we get a new protein, we start testing conditions with the sparse
matrix sampling screen.  The modifications you described (tyrosinated &
glycosylated) may indeed interfere with your crystallization (the protein
needs to be a pure/homogeneous as possible). However, diffraction quality
crystals have been obtained from heterogeneous mixtures of a protein!  Happy
screening!

Annie Hassell
Glaxo Research Institute
amh12478 at usav01.glaxo.com