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对已克隆的环状芽孢杆菌（Ｂａｃｉｌｕｓｃｉｒｃｕｌａｎｓ）Ｃ－２的几丁酶基因（Ｃｈｉ１）片段所作的亚克隆分析表明，该几丁酶基因位于１．７ｋｂＰｓｔⅠ－ＳｔｙⅠ片段上。Ｃｈｉ１基因在大肠杆菌（Ｅｓｃｈｅｒｉｃｈｉａｃｏｌｉ）ＪＭ１０７，ＤＨ５α，ＸＬ１－ｂｌｕｅ，ＴＧ－１等菌株中均能表达，但表达水平不同，其中ＪＭ１０７的表达活性最高，其胞外几丁酶活性与供体菌Ｃ－２菌株的胞外酶活性几乎相当。经ＳＤＳ－聚丙烯酰胺凝胶电泳分析，重组质粒ｐＣＨＩ１所产生的胞外几丁酶分子量为６６ｋＤ，与环状芽孢杆菌Ｃ－２的胞外蛋白质中相应的几丁酶蛋白分子量相同。Ｃｈｉ１基因在大肠杆菌ＪＭ１０７中表达后的细胞定位测定表明，几丁酶不仅存在于胞周间质和胞内，而且大量存在于培养物上清液中。在高产酶时期，胞外、胞周间质和胞内的酶活性分布分别为３５．８％，３２．１％，３２．９％
Subcloning of the chitin gene (Chi1) fragment of the cloned Bacilus circulans C-2 revealed that the chitinase gene is located on the 1.7 kb PstI-StyI fragment. The Chi1 gene was expressed in Escherichia coli JM107, DH5α, XL1-blue, TG-1 and other strains, but the expression levels were different. Among them, the expression activity of JM107 was the highest, -2 strain of extracellular enzyme activity is almost the same. SDS-polyacrylamide gel electrophoresis analysis, recombinant plasmid pCHI1 produced by the extracellular chitinase molecular weight of 66kD, and Bacillus circus Bacillus C-2 protein corresponding chitinase protein molecular weight. The cell localization of Chi1 gene after expressed in E. coli JM107 showed that chitinase was not only found in the interstitial and intracellular compartments but also in the culture supernatant. During the period of high-yielding enzyme, the extracellular, interstitial and intracellular enzyme activities were 35.8%, 32.1%, 32.9%