Article

Effect of exchange of amino acid residues of the surface region of the PST-01 protease on its organic solvent-stability.

Department of Chemical Engineering, Osaka Prefecture University, 1-1 Gakuen-cho, Naka-ku, Sakai, Osaka 599-8531, Japan.
Biochemical and Biophysical Research Communications (impact factor: 2.48). 08/2007; 358(4):1028-33. DOI:10.1016/j.bbrc.2007.05.047 pp.1028-33
Source: PubMed

ABSTRACT The PST-01 protease from an organic solvent tolerant Pseudomonas aeruginosa has high stability and activity in the presence of various organic solvents. The structure gene of the PST-01 protease was amplified by the error-prone PCR method. The mutated proteases were incubated in the presence of acetonitrile. By measuring remaining activities, two kinds of mutated PST-01 proteases of which the stabilities were changed were selected. These mutations hardly changed the profile of the activity and stability at various pHs. Their activity and stability at higher temperatures were slightly lower than those of the wild-type PST-01 protease. The stabilities of the mutated enzymes in the presence of various organic solvents were greatly reduced. In both the mutated PST-01 proteases, amino acids located at the surface of the enzyme had been substituted.

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Keywords

acetonitrile
 
amino acids
 
error-prone PCR method
 
higher temperatures
 
kinds
 
mutated enzymes
 
mutated proteases
 
mutated PST-01 proteases
 
mutations
 
organic solvent tolerant Pseudomonas aeruginosa
 
PST-01 protease
 
stabilities
 
structure gene
 
various organic solvents
 
wild-type PST-01 protease
 

Hiroyasu Ogino