生孢噬纤维粘菌基因文库的构建和纤维素酶基因的克隆

将生孢噬纤维粘菌（ＳｐｏｒｏｃｙｔｏｐｈａｇａＢ２９）染色体用ＰｓｔＩ部分酶切后，连接到大肠杆菌（Ｅ．ｃｏｌｉ）质粒载体ｐＵＣ８上，然后转化Ｅ．ｃｏｌｉＪＭ８３，从而建立了Ｂ２９的基因文库，并筛选一个含有内切葡聚糖纤维素酶（ＣＭＣａｓｅ）的阳性克隆．从此阳性克隆中提取质粒再转化ＪＭ８３，发现所有的氨苄青霉素抗性（Ａｐｒ）转化子都具有ＣＭＣａｓｅ酶活性，证明在大肠杆菌中克隆到一个Ｂ２９的内切葡聚糖酶基因．

Construction of Sporocytophaga B29 gene library and clouiug of CMCase gene

An endoglucanase(CMCase)gene from Sporocytophaga B29 was cloned in Escherichia coli JM83. The chromosomal DNA of B29 was partially digested with restriction enzyme PstI and ligated into the plasmid pUC8 that had been linearized with the same enzyme.After transformation of JM83,the gene library of B29 was constructed and an endoglucanase-positive clone was detected in situ.All transformants with Ap had the activity of CMCase,proving that what we cloned was a CMCase gene.