Expression of Escherichia coli SecB in Bacillus subtilis facilitates secretion of the SecB-dependent maltose-binding protein of E. coli.
نویسنده
چکیده
Less than 20% of the Escherichia coli maltose-binding protein (MBP) synthesized in Bacillus subtilis is exported. However, a portion of the secreted MBP was processed cotranslationally. Coexpression of SecB, a secretion-related chaperone of E. coli, stimulated posttranslational export of MBP in B. subtilis but inhibited its cotranslational processing. Export of a SecB-independent MBP-ribose-binding protein hybrid precursor was not enhanced by SecB. A slowly folding MBP derivative (MBP-Y283D) was more efficiently secreted than wild-type MBP, suggesting that the antifolding activity of SecB promotes posttranslational secretion of MBP in B. subtilis.
منابع مشابه
Functional implementation of the posttranslational SecB-SecA protein-targeting pathway in Bacillus subtilis.
Bacillus subtilis and its close relatives are widely used in industry for the Sec-dependent secretory production of proteins. Like other Gram-positive bacteria, B. subtilis does not possess SecB, a dedicated targeting chaperone that posttranslationally delivers exported proteins to the SecA component of the translocase. In the present study, we have implemented a functional SecB-dependent prote...
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عنوان ژورنال:
- Journal of bacteriology
دوره 176 16 شماره
صفحات -
تاریخ انتشار 1994