Hop resistance in the beer spoilage bacterium Lactobacillus brevis is mediated by the ATP-binding cassette multidrug transporter HorA

K Sakamoto, A Margolles, HW van Veen, WN Konings*

*Corresponding author for this work

Research output: Contribution to journalArticleAcademicpeer-review

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Lactobacillus brevis is a major contaminant of spoiled beer. The organism can grow in beer in spite of the presence of antibacterial hop compounds that give the beer a bitter taste. The hop resistance in L. brevis is, at least in part, dependent on the expression of the horA gene. The deduced amino acid sequence of HorA is 53% identical to that of LmrA, an ATP-binding cassette multidrug transporter in Lactococcus lactis. To study the role of HorA in hop resistance, HorA was functionally expressed in L. lactis as a hexa-histidine-tagged protein using the nisin-controlled gene expression system. HorA expression increased the resistance of L. lactis to hop compounds and cytotoxic drugs. Drug transport studies with L. lactis cells and membrane vesicles and with proteoliposomes containing purified HorA protein identified HorA as a new member of the ABC family of multidrug transporters.

Original languageEnglish
Pages (from-to)5371-5375
Number of pages5
JournalJournal of Bacteriology
Issue number18
Publication statusPublished - Sep-2001


  • GENE
  • LMRA

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