Post-translational processing of Neisseria meningitidis gamma-glutamyl aminopeptidase and its association with inner membrane facing to the cytoplasmic space.
We previously demonstrated that gamma-glutamyl aminopeptidase (also called gamma-glutamyl transpeptidase) (GGT) of Neisseria meningitidis is involved in the bacterial multiplication in cerebrospinal fluid. To further understand the function of meningococcal GGT, the biochemical properties were investigated in this study. The deduced amino acid sequence in N. meningitidis GGT was 37% identical to that of Escherichia coli GGT and that of Helicobacter pylori GGT, respectively, while a typical signal sequence was not found at the N-terminus of meningococcal GGT. Western blotting using rabbit antiserum against recombinant meningococcal GGT protein demonstrated that the meningococcal GGT is processed into two subunits in N. meningitidis at the conserved amino acid, threonine 427. The experiments on subcellular fractionation suggested that the majority of meningococcal GGT is associated with inner membrane facing to the cytoplasmic side. This cell localization might be unique for N. meningitidis compared to other GGTs.
Takahashi
Hideyuki
H
Department of Bacteriology, National Institute of Infectious Diseases, Toyama 1-23-1, Shinjuku-ku, Tokyo 162-8640, Japan. hideyuki@nih.go.jp
Watanabe
Haruo
H
D000595:Amino Acid Sequence; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism; D015153:Blotting, Western; D002458:Cell Fractionation; D003001:Cloning, Molecular; D004926:Escherichia coli / Q000235:genetics; D017353:Gene Deletion; D005798:Genes, Bacterial; D016480:Helicobacter pylori / Q000235:genetics; D008565:Membrane Proteins / Q000235:genetics / Q000378:metabolism*; D008969:Molecular Sequence Data; D016297:Mutagenesis, Site-Directed; D020125:Mutation, Missense; D009345:Neisseria meningitidis / Q000201:enzymology* / Q000235:genetics / Q000378:metabolism; D011499:Protein Processing, Post-Translational; D021382:Protein Sorting Signals; D016415:Sequence Alignment; D017386:Sequence Homology, Amino Acid; D013347:Subcellular Fractions / Q000378:metabolism; D013912:Threonine / Q000235:genetics; D005723:gamma-Glutamyltransferase / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*
D001426:Bacterial Proteins; D008565:Membrane Proteins; D021382:Protein Sorting Signals; D013912:Threonine; D005723:gamma-Glutamyltransferase