L-azetidine-2-carboxylic acid acetyltransferase; reduces intracellular ROS, contributes to L-proline analog resistance and tolerance to ethanol and freezing; member of N-acetyltransferase superfamily; not found in S288C, present in strains with Sigma1278b background; located on left arm of Chr X ~ 15 kb from telomere; identical to MPR1 except for one base at position 254, leading to Gly at position 85 in MPR1 and Glu in MPR2; present also in Japanese industrial baker's yeast