Designing a whole-cell biotransformation system in Escherichia coli using cytochrome P450 from Streptomyces peucetius
A biotransformation system was designed to co-express CYP107P3 (CSP4), cytochrome P450, from Streptomyces peuceticus, along with CamA (putidaredoxin reductase) and CamB (putidaredoxin) from Pseudomonas putida, the necessary reducing equivalents, in a class I type electron-transfer system in E. coli BL21 (DE3). This was carried out using two plasmids with different selection markers and compatible origins of replication. The study results showed that this biotransformation system was able to mediate the O-dealkylation of 7-ethoxycumarin.
In this paper, four kinds of culture media are used in detecting growth curve of isolating strain G3 of Clostridium perfringens type A and pH variety of culture solutions, thus compare producing toxins efficiency of this strain in above different culture media by detecting.The results showed that growth curve of this strain in four kinds of culture media are identical nearly, but pH variety of four culture solutions are discrepant and its range in cooked meat medium is lower than that in other media. And indicted that products and activities of Clostridium perfringens type A toxins in cooked meat medium are superior to that in others.and see that cooked meat medium was the suitable one for producing toxins of Clostridium perfringens type A.