| 摘要 |
PURPOSE:To produce beta-galactosidase, by preparing a recombinant DNA integrated with a vector having genetic information of thermostable beta-galactosidase derived from Thermus aquaticus, a highly thermophilic bacterium. CONSTITUTION:A bacterium belonging to the genus Thermus is cultivated, a mold is collected, blended with a lysozyme solution, kept warm for a fixed time, subjected to bacteriolysis with an SDS solution and then extracted with phenol. This DNA is recovered by ethanol precipitation and treated with RNase to give chromosome DNA. This chromosome DNA is completely or partially digested with a restriction enzyme and linked to vector plasmid DNA digested with a restriction enzyme leaving the same cleaved end by the se of ligase T4 to give a recombinant DNA. Escherichia coli having the recombinant DNA is cultivated and a mold thereof is ground by ultrasonic wave, etc., to give a crude enzyme solution of thermophilic beta-galactosidase. |
