The Application of a Novel Lytic System
to the Recovery of Recombinant Proteins in E.coli
YANG Yun-Gui, TONG Qin, HU Tai-Shan, QIAN You-Cun, YANG
Sheng-Li, GONG Yi*
( Shanghai Research Center of Biotechnology, Shanghai Institutes for
Biological Sciences, the
Chinese Academy of Sciences, Shanghai 200233, China )
Abstract In order to efficiently
recover recombinant proteins, a temperature-sensitive lytic system was constructed
on the basis of the feature that T4 lysozyme disrupts the bacteria through
cutting specific bond in the peptidoglycan layer of cell wall. This system was
evaluated by constructing and introducing a low copy plasmid pSC-lys
(pSC101 replication origin) into E.coli. The plasmid contained a
temperature sensitive T4 lysozyme (LYSts) gene under the control of
three tandem tac promoters and the LacI repressor, which is compatible
with other plasmids carrying pMB1, ColE1 replication origins, etc.
Under the optimum lysis conditions, 2―5 fold condensed cultures resuspended in
buffer A, β-galactosidase, recombinant chaperone GroEL and
ZZ-fusion salmon hexamic calcitonin (Cal6) in E.coli were released
simply, rapidly, and quantitatively, as co-expressed with LYSts. The
two tested recombinant proteins maintained their significant productions.
Instead of other cumbersome lysising methods, this novel lytic system will be
useful in recovery of recombinant proteins for further purification in the
field of biotechnology.
Key words E.coli； T4 lysozyme； lytic system； recombinant protein； β-galactosidase
Received: November
12, 1999 Accepted: December 9, 1999
The work was supported by a grant from the National High Technology
“863” Programs of China, No. 102-11-02-01
* Corresponding author: Tel, 86-21-64700892-371; Fax, 86-21-64700244; e-mail, [email protected]