caa a22 4500 605501149 CHVBK 20210128100559.0 cr unu---uuuuu 210128e20151101xx s 000 0 eng 10.1007/s00253-015-6741-8 doi (NATIONALLICENCE)springer-10.1007/s00253-015-6741-8 Aii20J, a wide-spectrum thermostable N -acylhomoserine lactonase from the marine bacterium Tenacibaculum sp. 20J, can quench AHL-mediated acid resistance in Escherichia coli [Elektronische Daten] [C. Mayer, M. Romero, A. Muras, A. Otero] Acyl homoserine lactones (AHLs) are produced by many Gram-negative bacteria to coordinate gene expression in cellular density dependent mechanisms known as quorum sensing (QS). Since the disruption of the communication systems significantly reduces virulence, the inhibition of quorumsensing processes or quorum quenching (QQ) represents an interesting anti-pathogenic strategy to control bacterial infections. Escherichia coli does not produce AHLs but possesses an orphan AHL receptor, SdiA, which is thought to be able to sense the QS signals produced by other bacteria and controls important traits as the expression of glutamate-dependent acid resistance mechanism, therefore constituting a putative target for QQ. A novel AHL-lactonase, named Aii20J, has been identified, cloned and over expressed from the marine bacterium Tenacibaculum sp. strain 20 J presenting a wide-spectrum QQ activity. The enzyme, belonging to the metallo-β-lactamase family, shares less than 31 % identity with the lactonase AiiA from Bacillus spp. Aii20J presents a much higher specific activity than the Bacillus enzyme, maintains its activity after incubation at 100 ºC for 10 minutes, is resistant to protease K and α-chymotrypsin, and is unaffected by wide ranges of pH. The addition of Aii20J (20 μg/mL) to cultures of E. coli K-12 to which OC6-HSL was added resulted in a significant reduction in cell viability in comparison with the acidresistant cultures derived from the presence of the signal. Results confirm the interaction between AHLs and SdiA in E. coli for the expression of virulence-related genes and reveal the potential use of Aii20J as anti-virulence strategy against important bacterial pathogens and in other biotechnological applications. Springer-Verlag Berlin Heidelberg, 2015 Quorum sensing nationallicence Quorum-quenching acylhomoserine lactones nationallicence Lactonase nationallicence E. coli nationallicence SdiA nationallicence Mayer C. Department of Microbiology and Parasitology, Faculty of Biology-CIBUS, University of Santiago de Compostela, 15782, Santiago de Compostela, Spain aut Romero M. Department of Microbiology and Parasitology, Faculty of Biology-CIBUS, University of Santiago de Compostela, 15782, Santiago de Compostela, Spain aut Muras A. Department of Microbiology and Parasitology, Faculty of Biology-CIBUS, University of Santiago de Compostela, 15782, Santiago de Compostela, Spain aut Otero A. Department of Microbiology and Parasitology, Faculty of Biology-CIBUS, University of Santiago de Compostela, 15782, Santiago de Compostela, Spain aut Applied Microbiology and Biotechnology Springer Berlin Heidelberg 99/22(2015-11-01), 9523-9539 0175-7598 99:22<9523 2015 99 253 https://doi.org/10.1007/s00253-015-6741-8 text/html Onlinezugriff via DOI BK010053 XK010053 XK010000 Metadata rights reserved Springer special CC-BY-NC licence nationallicence 1 research-article jats NATIONALLICENCE NATIONALLICENCE NL-springer NATIONALLICENCE 856 40 https://doi.org/10.1007/s00253-015-6741-8 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Mayer C. Department of Microbiology and Parasitology, Faculty of Biology-CIBUS, University of Santiago de Compostela, 15782, Santiago de Compostela, Spain aut NATIONALLICENCE 700 1- Romero M. Department of Microbiology and Parasitology, Faculty of Biology-CIBUS, University of Santiago de Compostela, 15782, Santiago de Compostela, Spain aut NATIONALLICENCE 700 1- Muras A. Department of Microbiology and Parasitology, Faculty of Biology-CIBUS, University of Santiago de Compostela, 15782, Santiago de Compostela, Spain aut NATIONALLICENCE 700 1- Otero A. Department of Microbiology and Parasitology, Faculty of Biology-CIBUS, University of Santiago de Compostela, 15782, Santiago de Compostela, Spain aut NATIONALLICENCE 773 0- Applied Microbiology and Biotechnology Springer Berlin Heidelberg 99/22(2015-11-01), 9523-9539 0175-7598 99:22<9523 2015 99 253