title: Evidence for propeptide-assisted folding of the calcium-dependent protease of the cyanobacterium Anabaena.
abstract: The Ca(2+)-dependent protease of the cyanobacterium Anabaena variabilis is a cytoplasmic enzyme with a substrate specificity like trypsin. Its previously published DNA sequence [Maldener, I., Lockau, W., Cai, Y. & Wolk, C. P. (1991) Mol. Gen. Genet. 225, 113-120] contained a sequencing error. Here we report the corrected sequence which shows, that the Ca(2+)-protease belongs to the family of subtilases (subtilisin-like serine proteases). Consistent with its cytoplasmic localization, a pre-sequence is not found. The enzyme is produced as a precursor with a large amino-terminal propeptide. Expression of the pro-region and mature region (protease domain) in Escherichia coli cells in trans demonstrates that formation of the active enzyme requires the propeptide. The results demonstrate that propeptide-assisted protein folding also occurs with cytoplasmic enzymes, in support of the hypothesis that this mechanism is a widespread phenomenon.
authors.affiliation: Institut für Biologie, Biochemie der Pflanzen, Humboldt-Universität zu Berlin, Germany.
authors.forename: K
authors.initials: K
authors.lastname: Baier
authors.forename: S
authors.initials: S
authors.lastname: Nicklisch
authors.forename: I
authors.initials: I
authors.lastname: Maldener
authors.forename: W
authors.initials: W
authors.lastname: Lockau
mesh_terms: D000595:Amino Acid Sequence; D017033:Anabaena / Q000201:enzymology* / Q000235:genetics; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism*; D001483:Base Sequence; D002118:Calcium / Q000378:metabolism; D002863:Chromogenic Compounds; D003001:Cloning, Molecular; D004926:Escherichia coli / Q000235:genetics; D005798:Genes, Bacterial; D008969:Molecular Sequence Data; D017510:Protein Folding; D011498:Protein Precursors / Q000235:genetics / Q000378:metabolism*; D011994:Recombinant Proteins / Q000378:metabolism; D015183:Restriction Mapping; D017422:Sequence Analysis, DNA; D013381:Subtilisins / Q000235:genetics / Q000378:metabolism*
chemical_list: D001426:Bacterial Proteins; D002863:Chromogenic Compounds; C102527:PrcA protein, bacteria; D011498:Protein Precursors; D011994:Recombinant Proteins; D013381:Subtilisins; D002118:Calcium