Microbial process for preparing pravastatin

The highest risk factor of atherosclerosis and especially coronary occlusion is the high cholesterol level of the plasma. In the last two decades 3-hydroxy-3-methylglutaryl coenzyme A reductase (EC.1.1.1.34) as the rate limiting key enzyme of the cholesterol biosynthesis was extensively examined. Pravastatin, a compound of Formula I, The present invention relates to a new microbial process for the preparation of the compound formula (I) from a compound of general formula (II) wherein R stands for an alkali metal or ammonium ion, by the submerged cultivation of a mold strain able to 6 -hydroxylate a compound of the Formula (II) in aerobic fermentation and by the separation and purification of the product of Formula (I) formed in the course of the bioconversion. The process comprises cultivating a strain of filamentous mold species that is able to 6 -hydroxylate a compound of the general Formula (II), on a nutrient medium containing assimilable carbon and nitrogen sources and mineral salts and separating the product formed from the fermentation broth, then isolating the compound of formula (I) and purifying the same. Novel strains of are also disclosed.