Li salts tend to increase the solubility of peptides (Seebach et al., Helv. Chim. Acta 72 (1989) 857-867), which is a pity, because they can also be used as cryoprotectants.
George Prof. George M. Sheldrick FRS Dept. Structural Chemistry, University of Goettingen, Tammannstr. 4, D37077 Goettingen, Germany Tel. +49-551-39-3021 or -3068 Fax. +49-551-39-2582 On Mon, 7 Apr 2008, Kay Diederichs wrote: > Dear all, > > a protein which we work on is available in low quantity. The only > crystallization screen we set up is completely clear, no precipitate, nothing. > > Now we would like to modify the reservoirs of this screen, by adding LiCl or > Ammoniumsulfate or ... , with the goal of reducing the vapour pressure, to at > least get the protein concentration in the drop into the range where > "something happens". > > Does anyone have advice as to which salt we should add (to the reservoir > only)? AmSO4 is only soluble to 4M, LiCl goes to 10M. But vapour pressure > reduction is not the same as molarity. > > thanks for any insight, > > Kay > -- > Kay Diederichs http://strucbio.biologie.uni-konstanz.de > email: [EMAIL PROTECTED] Tel +49 7531 88 4049 Fax 3183 > Fachbereich Biologie, Universität Konstanz, Box M647, D-78457 Konstanz > >
