TY - JOUR
T1 - A region of the transmembrane regulatory protein ToxR that tethers the transcriptional activation domain to the cytoplasmic membrane displays wide divergence among vibrio species
AU - Osorio, Carlos R.
AU - Klose, Karl E.
PY - 2000/1
Y1 - 2000/1
N2 - The virulence regulatory protein ToxR of Vibrio cholerae is unique in that it contains a cytoplasmic DNA-binding-transcriptional activation domain, a transmembrane domain, and a periplasmic domain. Although ToxR and other transmembrane transcriptional activators have been discovered in other bacteria, little is known about their mechanism of activation. Utilizing degenerate oligonucleotides and PCR, we have amplified internal toxR gene sequences from seven Vibrio and Photobacterium species and subspecies, demonstrating that toxR is an ancestral gene of the family Vibrionaceae. Sequence alignment of all available ToxR amino acid sequences revealed a region between the transcriptional activation and transmembrane domains that displays wide divergence among Vibrio species. We hypothesize that this region merely tethers the transcriptional activation domain to the cytoplasmic membrane and thus can tolerate wide divergence and multiple insertions and deletions. The divergence in the tether region at the nucleotide level may provide a useful tool for the distinction of Vibrio and Photobacterium species.
AB - The virulence regulatory protein ToxR of Vibrio cholerae is unique in that it contains a cytoplasmic DNA-binding-transcriptional activation domain, a transmembrane domain, and a periplasmic domain. Although ToxR and other transmembrane transcriptional activators have been discovered in other bacteria, little is known about their mechanism of activation. Utilizing degenerate oligonucleotides and PCR, we have amplified internal toxR gene sequences from seven Vibrio and Photobacterium species and subspecies, demonstrating that toxR is an ancestral gene of the family Vibrionaceae. Sequence alignment of all available ToxR amino acid sequences revealed a region between the transcriptional activation and transmembrane domains that displays wide divergence among Vibrio species. We hypothesize that this region merely tethers the transcriptional activation domain to the cytoplasmic membrane and thus can tolerate wide divergence and multiple insertions and deletions. The divergence in the tether region at the nucleotide level may provide a useful tool for the distinction of Vibrio and Photobacterium species.
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U2 - 10.1128/JB.182.2.526-528.2000
DO - 10.1128/JB.182.2.526-528.2000
M3 - Article
C2 - 10629204
AN - SCOPUS:0033988967
VL - 182
SP - 526
EP - 528
JO - Journal of Bacteriology
JF - Journal of Bacteriology
SN - 0021-9193
IS - 2
ER -