4907-76-0Relevant articles and documents
Hoener et al.
, p. 1901,1903 (1974)
Design and optimization of an enzymatic membrane reactor for tetracycline degradation
De Cazes,Belleville,Petit,Llorca,Rodríguez-Mozaz,De Gunzburg,Barceló,Sanchez-Marcano
, p. 146 - 152 (2014)
The tetracycline, antibiotic considered as a recalcitrant pollutant, was successfully depleted from model aqueous solutions by immobilized laccase from Trametes versicolor in an enzymatic membrane reactor. The results obtained show that tetracycline is depleted from water solutions at room temperature and without adding any extra chemicals. The degradation of tetracycline in aqueous solutions at 20 mg L-1 during 24 h, with equivalent amounts of free or immobilized biocatalyst, allowed reaching a tetracycline degradation yield of 56% with an enzymatic membrane whereas it was only of 30% with free laccase. This result highlights the good reactivity and stability of the immobilized enzyme for the degradation of tetracycline. Moreover, the enzymatic membrane reactor was able to reach a constant degradation rate of 0.34 mg of tetracycline per hour during 10 days.
Identifying the minimal enzymes required for anhydrotetracycline biosynthesis
Zhang, Wenjun,Watanabe, Kenji,Cai, Xiaolu,Jung, Michael E.,Tang, Yi,Zhan, Jixun
, p. 6068 - 6069 (2008/12/20)
The cyclohexenone ring A of tetracyclines exhibits unique structural features not observed among other aromatic polyketides. These substitutions include the C2 primary amide, C4 dimethylamine, and the C12a tertiary alcohol. Here we report the identification and reconstitution of the minimum set of enzymes required for the biosynthesis of anhydrotetracycline (ATC, 5), the first intermediate in the tetracycline biosynthetic pathway that contains the fully functionalized ring A. Using a combination of in vivo and in vitro approaches, we confirmed OxyL, OxyQ, and OxyT to be the only enzymes required to convert 6-methylpretetramid 1 into 5. OxyL is a NADPH-dependent dioxygenase that introduces two oxygen atoms into 1 to yield the unstable intermediate 4-keto-ATC 2. The aminotransferase OxyQ catalyzes the reductive amination of C4-keto of 2, yielding 4-amino-ATC 3. Furthermore, the N,N-dimethyltransferase OxyT catalyzes the formation of 5 from 3 in a (S)-adenosylmethionine (SAM)-dependent manner. Finally, a non-natural anhydrotetracycline derivative was generated, demonstrating that our heterologous host/vector pair can be a useful platform toward the engineered biosynthesis of tetracycline analogues. Copyright
