Cloning and organization of the abc and mdl genes of Escherichia coli: relationship to eukaryotic multidrug resistance

Gene. 1993 Dec 22;136(1-2):231-6. doi: 10.1016/0378-1119(93)90470-n.


Using degenerate oligodeoxyribonucleotides from conserved regions of the gene family encoding ATP-binding domain of the active transporter, two new Escherichia coli genes were identified. The first of the genes, named mdl (multidrug resistance-like), is located at min 10.2 of the E. coli chromosome and encodes two ATP-binding motifs and two hydrophobic (transmembrane) domains. The ATP-binding domains of mdl show 35-38% amino acid (aa) identity with members of the eukaryotic P-glycoprotein/multidrug resistance family. To date, 25 members of the ATP-transporter/permease gene family have been characterized in E. coli. Comparison of the ATP-binding domains from this family indicates that mdl is part of a distinct subfamily of sequences that includes hlyB, msbA, and cvaB. Gene-disruption studies revealed that mdl is not essential for cell growth. The second open reading frame, named abc (ATP-binding cassette), is located at min 4.9 of the chromosome, encodes a single ATP-binding domain, and is most homologous to ftsE, a cell division control gene of E. coli. The abc gene product also shows aa sequence homology to several E. coli permeases.

MeSH terms

  • ATP Binding Cassette Transporter, Subfamily B, Member 1
  • ATP-Binding Cassette Transporters*
  • Adenosine Triphosphate
  • Amino Acid Sequence
  • Bacterial Proteins / genetics*
  • Base Sequence
  • Carrier Proteins / genetics*
  • Chromosome Mapping
  • Cloning, Molecular
  • DNA, Bacterial
  • Drug Resistance, Microbial / genetics*
  • Escherichia coli / drug effects
  • Escherichia coli / genetics*
  • Escherichia coli Proteins*
  • Genes, Bacterial*
  • Humans
  • Membrane Glycoproteins / genetics
  • Membrane Proteins / genetics
  • Molecular Sequence Data


  • ATP Binding Cassette Transporter, Subfamily B, Member 1
  • ATP-Binding Cassette Transporters
  • Bacterial Proteins
  • Carrier Proteins
  • DNA, Bacterial
  • Escherichia coli Proteins
  • Membrane Glycoproteins
  • Membrane Proteins
  • mdlB protein, E coli
  • Adenosine Triphosphate

Associated data

  • GENBANK/L08626
  • GENBANK/L08627
  • GENBANK/L15362
  • GENBANK/L15363
  • GENBANK/L24529
  • GENBANK/X72987
  • GENBANK/X72988
  • GENBANK/X72989
  • GENBANK/Z15047
  • GENBANK/Z15048