Characterization of the critical amino acids of an aspergillus parasiticus cytochrome P-450 monooxygenase encoded by orda that is involved in the biosynthesis of aflatoxins B1, G1, B2, G2 - Bhatnagar, Deepak.; Cary, Jeffrey W.; Chang, Perng-Kuang.; Cleveland, Thomas E.; Dyer, John M.; Ehrlich, Kenneth C.; Montalbano, Beverly.; Yu, Jiujiang.