Hi, In addition to selenomet and various cocrystallization attempts, directed iodination of specific Tyr residues prior to crystallization may also be helpful.
Cheers, Melanie -----Original Message----- From: CCP4 bulletin board on behalf of Priyank Maindola Sent: Thu 6/28/2007 10:28 AM To: [email protected] Subject: [ccp4bb] heavyatom soaking problem Hello all, I am struggling with getting the phases out for my protein. Heavyatom database shows that only mercury and samarium have the binding motifs in it. Sodium iodide soak is killing the crystal even as less as 0.2 Molar concentration for 30sec. With Potassium iodide crystal is okay upto 0.75M for 1 & a half min but the incorporation is not at relevent sites.(Iodide signal is not distinct and is weak) Hg & Au salts precipitate it. With Pt signal is weak. Somewhere I read that high salt causes problems for heavy atom to bind to protein.My protein needs high salt for stability (750mM NaCl) Please help with some suggestion!!
