| 摘要 |
PURPOSE:To obtain D-amino acid oxidase(DAO) useful for organizing DAO manifestation vector, showing catalytic activity to catalyze conversion of cephalosporin C to a specific cephalosporanic acid derivative and having specific peptide sequence and molecular weight. CONSTITUTION:DAO drived from F. solani M-0718, catalyzing conversion of cephaloporin C (CC) to 7-beta-(5-carboxy-5-oxopentanamido)cephalosporanic acid (keto-AD-7ACA) is purified from a mycelium. Then mRNA of DAO is isolated, the mRNA is reversed to give cDNA, a cDNA library is prepared and probed to clone DNA to code DAO. Further the DNA is integrated into a proper manifestation vector to organize DNA manifestation vector, the vector is transduced to a host of Escherichia coli to give a transformant, which is cultured to manifest DAO in the transformant. The DAO has 40,000+ or -1,000 dalton molecular weight and peptide sequence containing peptide fraction AP-1--9 shown by the sequence formula. |
