Cloning, expression, purification, crystallization and preliminary X-ray analysis of peptidyl-tRNA hydrolase from Mycobacterium tuberculosis

Peptidyl-tRNA hydrolase catalyses the cleavage of the ester link between the peptide and the tRNA in peptidyl-tRNAs that, for various reasons, have dropped off the translating ribosomes. This enzyme from Mycobacterium tuberculosis has been crystallized in three related but distinct forms: $P2_12_12_1$, unit-cell parameters a = 36.30, b = 61.85, c = 73.97 \AA , $P2_1$, a = 35.83, b = 73.79, c = 59.79 \AA ,$_\beta$ = 92.3, and $P2_12_12_1$, a = 35.84, b = 57.06, c = 72.59 \AA . X-ray data have been collected from all three forms