The effects of N-acylhomoserine lactones, β-lactam antibiotics and adenosine on biofilm formation in the multi-β-lactam antibiotic-resistant bacterium Acidovorax sp. strain MR-S7.
Bacteria in the natural ecosystem frequently live as adherent communities called biofilms. Some chemical compounds are known to affect biofilm formation. We investigated the effect of exogenous small molecules, N-acylhomoserine lactones (AHLs), β-lactam antibiotics, and adenosine, on biofilm formation in the β-lactam antibiotic-resistant bacterium Acidovorax sp. strain MR-S7. Biofilm formation was induced by the addition of various types of AHL isomers and β-lactam antibiotics, whereas the addition of adenosine strongly interfered with the biofilm formation. A gene (macP) encoding adenosine deaminase (that converts adenosine to inosine controlling intracellular adenosine concentration) was successfully cloned from MR-S7 genome and heterologously expressed in Escherichia coli. The purified MacP protein clearly catalyzed the deamination of adenosine to produce inosine. A transcriptional analysis revealed that biofilm-inducing molecules, an AHL and a β-lactam antibiotic, strongly induced not only biofilm formation but also adenosine deaminase gene expression, suggesting that an elaborate gene regulation network for biofilm formation is present in the β-lactam antibiotic-resistant bacterium studied here.
Graduate School of Life and Environmental Sciences, University of Tsukuba, 1-1-1 Ten-nodai, Tsukuba, Ibaraki 305-8572, Japan; Bioproduction Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), 1-1-1 Higashi, Tsukuba, Ibaraki 305-8566, Japan. Electronic address: kusada-hiroyuki@aist.go.jp.
Hiroyuki
H
Kusada
Graduate School of Life and Environmental Sciences, University of Tsukuba, 1-1-1 Ten-nodai, Tsukuba, Ibaraki 305-8572, Japan; Bioproduction Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), 1-1-1 Higashi, Tsukuba, Ibaraki 305-8566, Japan. Electronic address: s-hanada@aist.go.jp.
Satoshi
S
Hanada
Bioproduction Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), 1-1-1 Higashi, Tsukuba, Ibaraki 305-8566, Japan. Electronic address: y.kamagata@aist.go.jp.
Yoichi
Y
Kamagata
Bioproduction Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), 1-1-1 Higashi, Tsukuba, Ibaraki 305-8566, Japan. Electronic address: n-kimura@aist.go.jp.
Nobutada
N
Kimura
D054742:Acyl-Butyrolactones / Q000378:metabolism / Q000494:pharmacology*; D000241:Adenosine / Q000494:pharmacology*; D000243:Adenosine Deaminase / Q000235:genetics; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D018441:Biofilms / Q000187:drug effects*; D042621:Comamonadaceae / Q000187:drug effects* / Q000235:genetics / Q000378:metabolism; D024901:Drug Resistance, Multiple, Bacterial / Q000187:drug effects; D018440:beta-Lactam Resistance; D047090:beta-Lactams / Q000494:pharmacology*
D054742:Acyl-Butyrolactones; D000900:Anti-Bacterial Agents; D047090:beta-Lactams; D000243:Adenosine Deaminase; D000241:Adenosine
Adenosine; Adenosine deaminase; Biofilm formation; Quorum sensing; β-Lactam antibiotic