Crystallization of quinohaemoprotein alcohol dehydrogenase from Comamonas testosteroni: crystals with unique optical properties

Quinohaemoprotein alcohol dehydrogenase from Comamonas testosteroni is a fu nctional electron-transfer protein containing both a haem c and a pyrroloqu inoline quinone cofactor. The enzyme has been crystallized at 277 K using p olyethylene glycol 6000 as precipitant. The crystals belong to space group C2, with unit-cell parameters a = 98.1, b = 74.3, c = 92.2 Angstrom, beta = 105.9 degrees. A native data set with a resolution of 2.44 Angstrom resolu tion has been collected. The approximate orientation of the haem group with respect to the unit-cell axes has been determined from the optical propert ies of the crystals.