Open AccessRequirement of a COOH‐terminal pro‐sequence for the extracellular secretion of aqualysin I (a thermophilic subtilisin‐type protease) in Thermus thermophilus
Author(s) -
Lee YoungChoon,
Koike Hideaki,
Taguchi Hayao,
Ohta Takahisa,
Matsuzawa Hiroshi
Publication year - 1994
Publication title -
fems microbiology letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.899
H-Index - 151
eISSN - 1574-6968
pISSN - 0378-1097
DOI - 10.1111/j.1574-6968.1994.tb07009.x
Subject(s) - thermus thermophilus , plasmid , biology , escherichia coli , mutant , enzyme , biochemistry , secretion , peptide sequence , extracellular , microbiology and biotechnology , thermus , subtilisin , gene , thermophile
Thermus thermophilus cells harboring an expression plasmid for the aqualysin I gene secrete the mature enzyme into the medium. In an Escherichia coli expression system, a precursor of the enzyme with the C‐terminal pro‐sequence is accumulated in the cells, and upon treatment at 65°C the active enzyme is produced. One‐ to 10‐amino acid residue deletions, as well as complete 105‐residue deletion of the C‐terminal pro‐sequence from the C‐terminus, did not affect the production of the enzyme in T. coli cells. T. thermophilus cells harboring plasmids for mutant precursors with one‐ and three‐residue deletions secreted the enzyme extracellularly. However, transformants harboring plasmids for mutant precursors with deletions of five or more amino acid residues could not be obtained. These results suggest that the C‐terminal pro‐sequence plays an important role in the extracellular secretion of the enzyme in T. thermophilus cells.