TY - JOUR
T1 - The 3' conserved segment of integrons contains a gene associated with multidrug resistance to antiseptics and disinfectants
AU - Paulsen, I. T.
AU - Littlejohn, T. G.
AU - Radstrom, P.
AU - Sundstrom, L.
AU - Skold, O.
AU - Swedberg, G.
AU - Skurray, R. A.
PY - 1993
Y1 - 1993
N2 - Nucleotide sequence analysis of ORF1 from the integron on the broad-host- range plasmid R751 revealed that the first 94 of 110 codons of ORF1 from R751 are identical to ORF4, an open reading frame from the 3' conserved segment of other integrons found in gram-negative bacteria, after which point they diverged completely. The predicted products of both ORF1 and ORF4 share homology with the multidrug exporter QacC. Phenotypic analysis revealed that ORF1 specifies a resistance profile to antiseptics and disinfectants almost identical to that of qacC, whereas ORF4 specifies much lower levels of resistance to these compounds. ORF4, whose product lacks the C-terminal 16 amino acids of the ORF1 protein, may have evolved by the interruption of ORF1 from the insertion of a DNA segment carrying a sull sulfonamide resistance determinant. Hence, ORF1 was designated qacE, and its partially functional deletion derivative, ORF4, was designated qacEΔ1. Fluorimetric experiments indicated that the mechanism of resistance mediated by QacE, the protein specified by qacE, is active export energized by proton motive force. Amino acid sequence comparisons revealed that QacE is related to a family of small multidrug export proteins with four transmembrane segments.
AB - Nucleotide sequence analysis of ORF1 from the integron on the broad-host- range plasmid R751 revealed that the first 94 of 110 codons of ORF1 from R751 are identical to ORF4, an open reading frame from the 3' conserved segment of other integrons found in gram-negative bacteria, after which point they diverged completely. The predicted products of both ORF1 and ORF4 share homology with the multidrug exporter QacC. Phenotypic analysis revealed that ORF1 specifies a resistance profile to antiseptics and disinfectants almost identical to that of qacC, whereas ORF4 specifies much lower levels of resistance to these compounds. ORF4, whose product lacks the C-terminal 16 amino acids of the ORF1 protein, may have evolved by the interruption of ORF1 from the insertion of a DNA segment carrying a sull sulfonamide resistance determinant. Hence, ORF1 was designated qacE, and its partially functional deletion derivative, ORF4, was designated qacEΔ1. Fluorimetric experiments indicated that the mechanism of resistance mediated by QacE, the protein specified by qacE, is active export energized by proton motive force. Amino acid sequence comparisons revealed that QacE is related to a family of small multidrug export proteins with four transmembrane segments.
UR - http://www.scopus.com/inward/record.url?scp=0027462796&partnerID=8YFLogxK
M3 - Article
C2 - 8494372
AN - SCOPUS:0027462796
SN - 0066-4804
VL - 37
SP - 761
EP - 768
JO - Antimicrobial Agents and Chemotherapy
JF - Antimicrobial Agents and Chemotherapy
IS - 4
ER -