title: Molecular cloning and expression of cellulase genes of alkalophilic Bacillus sp. strain N-4 in Escherichia coli.
abstract: The genes for cellulases of alkalophilic Bacillus sp. strain N-4 were cloned in Escherichia coli with pBR322. Plasmids pNK1 and pNK2 were isolated from the transformants producing carboxymethyl cellulase, and the carboxymethyl cellulase genes cloned were in 2.0- and 2.8-kilobase-pair HindIII fragments, respectively. On the DNA level, the pNK1 fragment had a different restriction map from that of the pNK2 fragment, but the genomic hybridization experiments showed partial homology among these fragments. A total of 74 and 34% of the enzyme activities were observed in the periplasmic space of E. coli carrying the plasmids pNK1 and pNK2 , respectively. The carboxymethyl cellulase thus produced had broad pH activity curves (pH of 5 to 10.9) and was stable up to 75 degrees C.
mesh_terms: D001407:Bacillus / Q000201:enzymology / Q000235:genetics*; D001483:Base Sequence; D002480:Cellulase; D003001:Cloning, Molecular; D004262:DNA Restriction Enzymes; D004269:DNA, Bacterial; D004926:Escherichia coli / Q000201:enzymology / Q000235:genetics*; D005798:Genes, Bacterial; D006026:Glycoside Hydrolases / Q000235:genetics* / Q000378:metabolism; D006358:Hot Temperature; D006863:Hydrogen-Ion Concentration; D008970:Molecular Weight; D009693:Nucleic Acid Hybridization; D010957:Plasmids
chemical_list: D004269:DNA, Bacterial; D004262:DNA Restriction Enzymes; D006026:Glycoside Hydrolases; D002480:Cellulase; C019826:carboxymethylcellulase