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Trehalose molecule is composed of two glucopyranose rings to an α, α - 1 , 1 - glycosidic linkage made ??of a very stable non-reducing disaccharide , which is widely present in nature of many biological body. Trehalose as a natural non-specific biological protection material , resistant to dehydration , freezing , high temperature , hypertonic , drought , oxidation , radiation and even toxic compounds adverse environmental conservation of biological cells and biologically active substances . Trehalose has been applied to many fields of medicine, cosmetics , food , and good market prospects . Currently, the production method of trehalose prepared by enzymatic - based . Among them, the use of TreS ways by the the maltose production of trehalose and TreY-TreZ ways the most economically feasible production of trehalose from starch . This article for the Corynebacterium glutamicum TreY-TreZ pathway TreZ protein that the maltooligosyl trehalose hydrolase (MTHase) , , gene cloning and heterologous expression . First cloned by PCR Corynebacterium glutamicum ATCC13032 MTHase ??of the gene encoding Trez length is 1764bp , insert it into the E. coli expression plasmid pRSET- B in the host bacteria , E.coli BL21 (DE3) pLysS , induced expression results obtained specific expression of the target protein . The optimal induction conditions , 40% of the total soluble protein in the dissolved recombinant protein accounted for approximately intracellular , per ml of fermentation broth can be expressed soluble target protein 0.27 mg , still part of the purpose of protein aggregation and formation of inclusion bodies . Testing confirmed by thin layer chromatography and ion chromatography , the target protein of Corynebacterium glutamicum maltooligosyl trehalose synthase (MTSase) jointly acting on the dextrin after trehalose can be generated , with the corresponding activity of the MTHase ??. Continue to build the Pichia yeast expression the carrier pPIC9K-treZ and Bacillus subtilis the expression the carrier pHT43 - treZ and were transformed into Pichia yeast (Pichia pastoris GS115) and Bacillus subtilis (B. subtilis WB800N), Corynebacterium glutamicum MTHase ??Can secretion expression in Pichia pastoris and Bacillus subtilis . Try different inducing conditions , was not observed in the induced culture supernatant of recombinant Pichia pastoris and recombinant Bacillus subtilis to the target protein .
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