title: Interaction of the Escherichia coli lipoprotein NlpI with periplasmic Prc (Tsp) protease.
abstract: Escherichia coli spr (suppressor of prc) mutants and nlpI mutants show thermosensitive growth. The thermosensitivity of the spr mutants was suppressed by the nlpI mutations. Expression of the fusion genes encoding hexa-histidine-tagged NlpI (NlpI-His) and purification of the tagged NlpI showed that NlpI-His bound with Prc protease and IbpB chaperone. NlpI-His with the amino acid substitution of G103D did not bind with either of these proteins, while NlpI-His variants (NlpI-284-His, NlpI-Q283-His, and NlpI-G282-His) lacking 10 to 12 residues from the carboxy terminus bound with both proteins. The tagged NlpI lacking 11 amino acid residues from the carboxy terminus was processed by Prc, but that lacking 12 residues was not. The thermosensitivity of the nlpI mutant was corrected by the production of the former NlpI variant, but not by production of the latter. Expression of the truncated NlpI that lacked 10 or 11 residues from the carboxy terminus corrected the thermosensitivity of the prc nlpI double mutant, while expression of the full-length NlpI did not. Thus, it was suggested that NlpI was activated by Prc protease processing.
authors.affiliation: Department of Biomolecular Sciences, Faculty of Science, Toho University, Miyama 2-2-1, Funabashi, Chiba, 274-8510. tadokoro@scl.kyoto-u.ac.jp
authors.forename: Akiko
authors.initials: A
authors.lastname: Tadokoro
authors.forename: Hidemi
authors.initials: H
authors.lastname: Hayashi
authors.forename: Toshihiko
authors.initials: T
authors.lastname: Kishimoto
authors.forename: Yasutaka
authors.initials: Y
authors.lastname: Makino
authors.forename: Shingo
authors.initials: S
authors.lastname: Fujisaki
authors.forename: Yukinobu
authors.initials: Y
authors.lastname: Nishimura
mesh_terms: D000595:Amino Acid Sequence; D001483:Base Sequence; D010450:Endopeptidases / Q000378:metabolism*; D004926:Escherichia coli / Q000378:metabolism*; D029968:Escherichia coli Proteins / Q000378:metabolism*; D006358:Hot Temperature; D008074:Lipoproteins / Q000737:chemistry / Q000378:metabolism*; D008969:Molecular Sequence Data; D009154:Mutation; D010957:Plasmids / Q000235:genetics; D013997:Time Factors
chemical_list: D029968:Escherichia coli Proteins; D008074:Lipoproteins; C120330:NlpI protein, E coli; D010450:Endopeptidases; C072135:C-terminal processing peptidase