Re: [ccp4bb] crystal Packing

[Roger Rowlett]

A really simple trick is to dilute your drops. This has worked to suppress excessive nucleation for us many times, and nearly always increases crystal size. For example, instead of setting drops with 1 uL of protein and 1 uL of well solution, try setting the drop with 1 uL of protein, 1 uL of water and 1 uL of well solution. You can increase the water volume even more if desired, up to 6-10x the protein/well volumes. The extra evaporation time will postpone concentration into the supersaturation zone. Cheers, On 8/19/2011 10:32 AM, Christian Biertuempfel wrote: Dear Eswar, You could try to slow down crystallization somehow. There are several ways to accomplish this: 1) increase drop size 2) add small amounts of glycerol (1-5% v/v) 3) cover the reservoir solution with paraffin or silicon oil or a mixture of both in order to reduce the vapor-diffusion rate 4) find another additive that would change the crystallization regime (e.g. kosmotropic/chaotropic agents) Good luck! christian On 08/18/2011 04:24 AM, eswar reddy wrote: Dear All I was working two domain protein and i have an hexagonal look like crystals from additive screen, now i am facing problem these crystal are growing in 2 minutes even in cold room even at lower protein concentration @2mg/ml . and i have an smeary data of 7 Å, and we thinking one domain might be flexible and other is stable is there anyway to increase the crystal packing .... Any suggestions are welcome. Eswar Reddy -- Roger S. Rowlett Gordon & Dorothy Kline Professor Department of Chemistry Colgate University 13 Oak Drive Hamilton, NY 13346 tel: (315)-228-7245 ofc: (315)-228-7395 fax: (315)-228-7935 email: rrowl...@colgate.edu