Isolation and characterization of the Haemophilus influenzae tolQ, tolR, tolA and tolB genes

Gene. 1996 Oct 31;178(1-2):75-81. doi: 10.1016/0378-1119(96)00338-1.


The tolQ, R, A and B genes have been isolated from the DNA of Haemophilus influenzae and sequenced. The deduced amino acid (aa) sequence of the H. influenzae TolQ, TolR, TolA and TolB show 67, 63, 41 and 62% identity with Escherichia coli TolQRAB proteins, respectively. These four proteins are involved in transport of colicins and phages across the cell envelope. The translational stop codon of TolB (the last gene in the cluster) is 23 bases upstream of the start codon of the P6 lipoprotein gene. Primer extension and Northern blot analysis revealed that the start of the P6 transcript is within the tolB gene. Nucleotide sequence (nt) analysis of the entire tolQRABP6 region shows a transcriptional terminator immediately downstream of the P6 gene. The tolQRABP6 gene cluster of H. influenzae may thus constitute an operon.

Publication types

  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Amino Acid Sequence
  • Bacterial Proteins / genetics
  • Base Sequence
  • Cloning, Molecular
  • DNA, Bacterial
  • Escherichia coli / genetics
  • Escherichia coli Proteins*
  • Genes, Bacterial*
  • Haemophilus influenzae / genetics*
  • Membrane Proteins*
  • Molecular Sequence Data
  • Multigene Family
  • Periplasmic Proteins*
  • RNA, Bacterial / genetics
  • RNA, Messenger / genetics
  • Sequence Homology, Amino Acid
  • Transcription, Genetic


  • Bacterial Proteins
  • DNA, Bacterial
  • Escherichia coli Proteins
  • Membrane Proteins
  • Periplasmic Proteins
  • RNA, Bacterial
  • RNA, Messenger
  • tolA protein, E coli
  • tolB protein, E coli
  • tolQ protein, E coli
  • tolR protein, E coli

Associated data

  • GENBANK/U32470