Hi, Last spring I visited the Protein Crystallography Station at Los Alamos. On a shelf, in a capillary in a serious exhibition-quality glass dome, was a crystal of myoglobin some 50 mm**3, if I remember correctly. I was told it had been made by Benno Schoenborn some decades earlier and had been exposed to most of the neutron sources in the world (radiation damage - forget about it!) Paul Langan or Zoë Fisher can correct me if I've exaggerated the size or age.
Anyway, as I already lost the record several times over for having seen the biggest protein crystal ever, I can share with you the surprise and delight of having to centre the crystals using a telescope mounted on a tripod on the other side of the room. Apparently the magnification on the microscope on the diffractometer (visible in this photo, and maybe the giant crystal too? http://www.lanl.gov/_assets/php/flickrImage.php?photo_id=5033219363&secret=291f519124) was too high, so any "neutron-size" crystals would filled the whole field of view even if they were not well-centered. FWIW, my crystals (somewhat optimistically 0.4 mm**3) didn't diffract neutrons even after a 24h exposure :-) Derek ________________________________________________________________________ Derek Logan tel: +46 46 222 1443 Associate Professor mob: +46 76 8585 707 Dept. of Biochemistry and Structural Biology www.cmps.lu.se Centre for Molecular Protein Science www.maxlab.lu.se/node/307 Lund University, Box 124, 221 00 Lund, Sweden On 24 Oct 2013, at 18:35, Victor Lamzin <vic...@embl-hamburg.de> wrote: > Also following on from John's comment - back to the times of my PhD I was > repeatedly growing crystals of bacterial formate dehydrogenase (80 kDa) of a > size about 7x1.5x1 mm. I thought that was quite normal and did not even think > of making a photo of 'just a protein crystal'. > > Victor
