| Autor: |
van Roosmalen, ML, Jongbloed, JDH, Kuipers, A, Venema, G, Bron, S, van Dijl, JM |
| Přispěvatelé: |
Groningen Biomolecular Sciences and Biotechnology, Cardiovascular Centre (CVC), Translational Immunology Groningen (TRIGR) |
| Jazyk: |
angličtina |
| Rok vydání: |
2000 |
| Předmět: |
|
| Zdroj: |
Journal of Bacteriology, 182(20), 5765-5770. AMER SOC MICROBIOLOGY |
| ISSN: |
0021-9193 |
| Popis: |
Soluble forms of Bacillus signal peptidases which lack their unique amino-terminal membrane anchor are prone to degradation, which precludes their high-level production in the cytoplasm of Escherichia coli. Here, we show that the degradation of soluble forms of the Bacillus signal peptidase SipS is largely due to self-cleavage. First, catalytically inactive soluble forms of this signal peptidase were not prone to degradation; in fact, these mutant proteins were produced at very high levels in E. coli. Second, the purified active soluble form of SipS displayed self-cleavage in vitro. Third, as determined by N-terminal sequencing, at least one of the sites of self-cleavage (between Ser15 and Met16 of the truncated enzyme) strongly resembles a typical signal peptidase cleavage site. Self-cleavage at the latter position results in complete inactivation of the enzyme, as Ser15 forms a catalytic dyad with Lys55. Ironically, self-cleavage between Ser15 and Met16 cannot be prevented by mutagenesis of Gly13 and Ser15, which conform to the -1, -3 rule for signal peptidase recognition, because these residues are critical for signal peptidase activity. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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