Hi James, Not as many responses on lysozyme crystallization as I would have expected. Or may be people thought you were joking (were you?). Anyhow, higher concentrations of lyso gives smaller crystals but if you let them grow on their own, you may get few huge ones instead. What worked for me was following streak-seeding: An acupuncture needle of 5- to 10-μm diameter was loaded with microcrystals by plunging it into a large crystal. Excess seeds were washed off by passing the needle through the well solution. Then, the crystallization drops were seeded by streaking the needle through the drops. Twelve drops were seeded successively with a single needle-load to achieve gradual dilution of seeds, resulting in a varying number and size of crystals. Happy seeding! N.
Ruslan Sanishvili (Nukri), Ph.D. GM/CA-CAT Biosciences Division, ANL 9700 S. Cass Ave. Argonne, IL 60439 Tel: (630)252-0665 Fax: (630)252-0667 rsanishv...@anl.gov -----Original Message----- From: CCP4 bulletin board [mailto:CCP4BB@JISCMAIL.AC.UK] On Behalf Of James Holton Sent: Tuesday, July 26, 2011 12:56 PM To: CCP4BB@JISCMAIL.AC.UK Subject: [ccp4bb] small lysozyme crystals? Does anyone out there have a protocol of growing HEWL crystals that are all 50-100 microns wide? I gave this project to a summer student recently, thinking it would be easy, but it is turning out to be more difficult than I thought. Keep getting sphereulites instead of small crystals. Yes, I know you can smash a large lysozyme crystal with a hammer, but that is not exactly what I was going for. What I was hoping for was a well-defined protocol for growing "reference" crystals that stay evenly illuminated in our x-ray beams as they rotate. The beam is 100 um wide. I'm sure someone has done this before? -James Holton MAD Scientist
