Open AccessCarboxy-Terminal Proteolytic Processing of Helicobacter pylori Vacuolating Toxin
Author(s) -
Viet Nguyen,
Richard M. Caprioli,
Timothy L. Cover
Publication year - 2001
Publication title -
infection and immunity
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.508
H-Index - 220
eISSN - 1070-6313
pISSN - 0019-9567
DOI - 10.1128/iai.69.1.543-546.2001
Subject(s) - toxin , biology , helicobacter pylori , microbiology and biotechnology , amino acid , proteolysis , peptide sequence , cleavage (geology) , signal peptidase , biochemistry , helicobacter , gene , signal peptide , genetics , enzyme , paleontology , fracture (geology)
The vacA gene of Helicobacter pylori strain 60190 encodes a 1, 287-amino-acid protoxin, which undergoes cleavage of a 33-amino-acid amino-terminal signal sequence and carboxy-terminal proteolytic processing to yield a mature secreted toxin. Several features of VacA suggest that it belongs to the autotransporter family of gram-negative bacterial secreted proteins. Based on matrix-assisted laser desorption ionization-time of flight mass spectrometric analysis, we calculate that the mature toxin has a mass of 88.2+/-0.2 kDa and consists of approximately 821 amino acids.