He X, Shen R, Sheng Z
Institute of Genetics, Fundan University, Shanghai.
Yi Chuan Xue Bao. 1990;17(4):313-20.
A 0.5kb fragment from Sau3A-digested total DNA of Bacillus stearothermophilus CU21 was cloned with the vector pPGV5, a derivative of pPL703. The insertion of this fragment can activate the expression of the promoteless cat-86 gene on the cloning vector in both B. stearothermophilus and Bacillus subtilis hosts. When the 0.54 kb fragment is present in pPGV5 in either orientation, the transformation efficiency of the plasmid is increased about 10(3) to 10(4) fold in CU21 protoplasts. Southern hybridization showed this 0.54 kb fragment was homologous with a 1.6kb fragment, which was shown by Imanaka et al. (1984, J. Gen. Microbiol. 130, 1399-1408) to originate in a cryptic plasmid resident in CU21 and to enhance the transformat on efficiency of another plasmid. With this 0.54kb fragment a new promoter probe vector pFDC4 and a gene expression vector pFDC11 were constructed. Both can transform the CU21 recipient with high efficiency.
用载体pPGV5（pPL703的衍生物）克隆了嗜热脂肪芽孢杆菌CU21经Sau3A酶切的总DNA中的一个0.5kb片段。该片段的插入可激活克隆载体上无启动子的cat-86基因在嗜热脂肪芽孢杆菌和枯草芽孢杆菌宿主中的表达。当0.54kb片段以任何方向存在于pPGV5中时，该质粒在CU21原生质体中的转化效率提高约10³至10⁴倍。Southern杂交表明，这个0.54kb片段与一个1.6kb片段同源，Imanaka等人（1984年，《普通微生物学杂志》130卷，1399 - 1408页）指出该1.6kb片段源自CU21中存在的一个隐蔽质粒，并能提高另一个质粒的转化效率。利用这个0.54kb片段构建了一个新的启动子探针载体pFDC4和一个基因表达载体pFDC11。二者都能高效转化CU21受体菌。
