Résumé
The strain JPL-2, capable of degrading fenoxaprop-P-ethyl (FE), was isolated from the soil of a wheat field and identified as Rhodococcus ruber. This strain could utilize FE as its sole carbon source and degrade 94.6% of 100 mg L−1 FE in 54 h. Strain JPL-2 could also degrade other aryloxyphenoxy propanoate (AOPP) herbicides. The initial step of the degradation pathway is to hydrolyze the carboxylic acid ester bond. A novel esterase gene feh, encoding the FE-hydrolyzing carboxylesterase (FeH) responsible for this initial step, was cloned from strain JPL-2. Its molecular mass was approximately 39 kDa, and the catalytic efficiency of FeH followed the order of FE > quizalofop-P-ethyl > clodinafop-propargyl > cyhalofop-butyl > fluazifop-P-butyl > haloxyfop-P-methyl > diclofop-methy, which indicated that the chain length of the alcohol moiety strongly affected the hydrolysis activity of the FeH toward AOPP herbicides.
Sujets)
Carboxylesterase/génétique , Carboxylesterase/métabolisme , Herbicides/métabolisme , Oxazoles/métabolisme , Propionates/métabolisme , Rhodococcus/isolement et purification , Rhodococcus/métabolisme , Biotransformation , Clonage moléculaire , Analyse de regroupements , Carboxylesterase/composition chimique , ADN bactérien/composition chimique , ADN bactérien/génétique , ADN ribosomique/composition chimique , ADN ribosomique/génétique , Données de séquences moléculaires , Masse moléculaire , Phylogenèse , /génétique , Protéines recombinantes/composition chimique , Protéines recombinantes/génétique , Protéines recombinantes/métabolisme , Rhodococcus/enzymologie , Rhodococcus/génétique , Analyse de séquence d'ADN , Microbiologie du sol , Spécificité du substrat , Triticum/croissance et développementRésumé
116 cases of facial pigmented spots were treated by the needle-embedding method in Uterus (MA-TF). EarShenmen (MA-TF1), Endocrine (MA-IC3) and Lung (MA-IC1) as the main points and the additional points selected based upon pattern identification. All cases were cured.