發(fā)布時(shí)間：2018-01-28 00:40

  本文關(guān)鍵詞： β-葡萄糖苷酶 多粘類(lèi)芽孢桿菌 克隆和表達(dá) 共表達(dá) 酶活　出處：《草業(yè)學(xué)報(bào)》2017年05期 　論文類(lèi)型：期刊論文

【摘要】：為了有效地提高β-葡萄糖苷酶的活性,本實(shí)驗(yàn)將多粘類(lèi)芽孢桿菌(Bacillus polymyxa)β-葡萄糖苷酶bglA、bglB和bgl(bglA和bglB基因)基因分別連接在pET-28a上并在大腸桿菌C41中表達(dá)。將這3株重組菌分別命名為EA、EB及共表達(dá)菌株EAB,并將構(gòu)建好的工程菌EA和EB按1∶1,1∶2,2∶1進(jìn)行混合培養(yǎng),分別比較單一酶組分、共表達(dá)及混合表達(dá)菌株的酶活。SDS-PAGE電泳圖顯示BglA和BglB的大小都為50ku,EA和EB混合培養(yǎng)的蛋白大小也為50ku,Bgl大小為100ku,表明BglA和BglB在體外不能形成蛋白復(fù)合物,只有在生物體內(nèi)才能形成Bgl復(fù)合蛋白。酶活測(cè)定結(jié)果表明共表達(dá)Bgl與多粘類(lèi)芽孢桿菌的酶活差異不顯著,但顯著高于其他組分酶活(P0.05)。剛果紅染色結(jié)果也表明Bgl酶活比單一酶組分的酶活明顯提高。本實(shí)驗(yàn)為纖維素酶多組分人工組裝及集成生物工藝菌種的構(gòu)建奠定實(shí)驗(yàn)基礎(chǔ)。
[Abstract]:In order to improve the activity of 尾 -glucosidase, Bacillus polymyxa- 尾 -glucosidase bglA was used in this experiment. BglB, bgl(bglA and bglB genes were linked to pET-28a and expressed in Escherichia coli C41. The three recombinant strains were named EA, respectively. EB and EAB were co-expressed, and the constructed engineering bacteria EA and EB were mixed by 1: 1 and 1: 1: 2: 1 to compare the single enzyme components. The enzyme activity. SDS-PAGE electrophoresis of co-expressed and mixed expression strains showed that the size of BglA and BglB were both 50ku and 50ku in mixed culture of EA and EB. The size of Bgl was 100ku. indicating that BglA and BglB could not form protein complexes in vitro. Only in vivo can Bgl complex protein be formed. The results of enzyme activity test showed that there was no significant difference between the enzyme activity of co-expressed Bgl and that of Bacillus polymyxides. But significantly higher than that of other components (P0.05). The results of Congo red staining also showed that the enzyme activity of Bgl was significantly higher than that of single enzyme component, which laid the experimental foundation for the artificial assembly of cellulase multicomponent and the construction of integrated biotechnological bacteria.
【作者單位】： 甘肅農(nóng)業(yè)大學(xué)動(dòng)物醫(yī)學(xué)學(xué)院;
【基金】：甘肅省科技支撐計(jì)劃項(xiàng)目(1204NKCA103) 國(guó)家自然科學(xué)基金青年項(xiàng)目(31500067)資助
【分類(lèi)號(hào)】：Q55;Q78
【正文快照】： 纖維素是植物材料的主要成分,植物通過(guò)光合作用的形式使光能以生物能的形式固定下來(lái),其生成量每年高達(dá)2000億t,其中50%以上為纖維素和半纖維素,這些能量相當(dāng)于全球人類(lèi)每年能源消耗量的20倍,食物中所含能量的200倍,是永遠(yuǎn)不會(huì)枯竭的可再生資源[1]。但由于纖維素具有水不溶性的，

本文編號(hào)：1469273