TolC and DsbA are needed for the secretion of STB, a heat-stable enterotoxin of Escherichia coli.
STB secretion-deficient mutants were isolated using the synthetic transposon Tn beta laM. Cultures were plated using a double-membrane system of cellulose acetate and nitrocellulose placed on Luria agar plates containing carbenicillin. The STB bound to the underlying nitrocellulose membrane was detected with anti-STB antibodies. The altered genes of two STB secretion-deficient mutants were identified by conjugation and complementation as tolC and dsbA. In cultures of well-characterized dsbA and tolC mutants, STB was absent from the culture supernatant. The role of TolC and DsbA in the secretion of peptides is discussed.
Foreman
D T
DT
Department of Microbiology, University of Texas Southwestern Medical Center, Dallas 75235-9048, USA.
Martinez
Y
Y
Coombs
G
G
Torres
A
A
Kupersztoch
Y M
YM
D001425:Bacterial Outer Membrane Proteins / Q000235:genetics / Q000502:physiology; D001427:Bacterial Toxins / Q000378:metabolism*; D002876:Chromosomes, Bacterial; D004768:Enterotoxins / Q000378:metabolism*; D004926:Escherichia coli / Q000235:genetics / Q000378:metabolism*; D029968:Escherichia coli Proteins; D005798:Genes, Bacterial; D007535:Isomerases / Q000235:genetics / Q000502:physiology; D026901:Membrane Transport Proteins; D009154:Mutation; D010957:Plasmids; D019704:Protein Disulfide-Isomerases
D001425:Bacterial Outer Membrane Proteins; D001427:Bacterial Toxins; D004768:Enterotoxins; D029968:Escherichia coli Proteins; D026901:Membrane Transport Proteins; C034151:heat stable toxin (E coli); C073126:tolC protein, E coli; D007535:Isomerases; D019704:Protein Disulfide-Isomerases