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P450 BM-3 from Bacillus megaterium having fatty acid hydroxylation activity of the enzyme, it has a rapid catalytic chain length of C12-C22 saturated fatty acid monooxygenase enzyme activity found in the life activity, drug synthesis, and other biocatalytic with important significance in the transformation process, but many studies have shown that the the enzyme presence of poor stability, low catalytic efficiency of non-natural substrates defects, has been a serious impediment to play its proper function and role. Currently, the foreign researchers are expected by various ways to enhance the stability and catalytic activity of the enzyme, but because of the lack of the enzyme protein structure and function information of, and yet to obtain a satisfactory result. Directed evolution technology change enzyme features and build new features enzyme shows great potential, such as P450BM-3 (A74G, F87V, L188Q) mutant catalytic indole to indigo, which is the wild-type P450 BM-3 does not have a catalytic function. Further directed evolution technology, we have successfully obtained three higher dynamic mutant enzyme catalyzed indole P450 BM-3 (139V; D168N, A225V K440N; E435D). In order to further study the changes of these mutant enzyme substrate specificity, the use of the mutant enzyme to a series of compounds of the benzene series, biocatalysis, found that these mutant enzymes can catalyze styrene styrene oxide is generated further hydrolysis of benzene glycol, determined by screening the mutant enzyme HML003 styrene maximum catalytic activity. P450 BM-3 in the catalytic process need cofactors, so we use whole cell biotransformation Method system of reaction time, the reaction system, temperature, substrate concentration, and co-solvent DMSO, glucose, feeding method of P450 BM- The 3 mutant enzyme catalyzed styrene ultimately generate benzene glycol. Determine the best whole cell biotransformation conditions for possible catalytic mechanism, the source of oxygen molecules in the air generated by styrene oxide monooxygenase, styrene oxide ternary The volatile big rings become prone to ring opening reaction of weak acid weak alkaline conditions, it is easy to generate anti-benzene glycol, and the monooxygenase enzymatic reaction due to coenzyme Ⅱ participation system was weak base The appropriate conditions, therefore, the hydrolysis reaction, and ultimately the formation of benzene glycol and the product is accumulated in the extracellular, easy extraction.
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