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Enoyl -ACP reductase (FabI) ??, is the enzyme necessary for the majority of bacterial fatty acid synthesis is a NADH -dependent single - function enzyme , this enzyme in eukaryotic cells , it has gradually become a hot target of the antibacterial drug research bit. The use of antisense RNA technology, building engineering bacteria ( E. coli / pHNF ) can effectively inhibit FabI expression . Using the engineered bacteria to build FabI target ultra- sensitive whole-cell the antibacterial drug screening model . Induced conditions of its antisense silencing effect , and triclosan and ampicillin were used as positive and negative controls , microplate detection , initially set the conditions of the the FabI targets specific whole-cell screening model is : inducer IPTG concentration of 37.5μmol / L, and the positive control triclosan concentration 25,37.5,50 microg / mL concentration of the negative control ampicillin 0.5,2.5,5 microg / mL , and cultured for 16 hours . This model for the screening of endophytic fungal fermentation samples were screened samples 5847 , of which 559 positive samples , the positive rate of 9.7% . Select the higher activity HCCB06314 strains for further research , through the observed strains macro and microscopic morphology , cultural characteristics as well as analysis of ITS sequence PCR results , classification and identification of HCCB06314 determine the strains belonging to Fusarium ( Fusarium sp ) . Strains HCCB6314 metabolites isolated and purified by silica gel chromatography and HPLC method , two secondary metabolites , and their structures were identified using mass spectrometry and nuclear magnetic resonance spectroscopy , determining HCCB06314-1 ex Fusarium avermectin I ( Enniatin I), HCCB06314-2 ex Fusarium avermectin H . Using UPLC-MS analysis of the sample 6314-10 , the sample there are 7 ex Fusarium cephalosporins (enniatins) compound , the compound wherein the molecular formula is C37H65N3O9 , through scinfinder retrieval fails to find relevant enniatin analogues may a new enniatin like.
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