Colloids Surf B 2010, 76:298–304 CrossRef 31 Irie Y, O’Toole GA,

Colloids Surf B 2010, 76:298–304.CrossRef 31. Irie Y, O’Toole GA, Yuk MH: Pseudomonas aeruginosa rhamnolipids disperse Bordetella bronchiseptica biofilms. FEMS Microbiology Lett 2005, 250:237–243.CrossRef 32. Mireles JR, Toguchi A, Harshey RM: Salmonella enterica serovar Typhimurium swarming mutants with altered biofilm-forming abilities: surfactin inhibits biofilm formation. J Bacteriol 2001, 183:5848–5854.PubMedCrossRef Authors’ contributions TJ carried out experiments, ML participated in the design of the study, data analysis, coordination and helped to draft the

manuscript, AK conceived the experiments and draft the manuscript. All authors read and approved the final manuscript.”
“Background Biogenic amines (BA) are low molecular weight organic bases present in a wide NU7026 in vivo range of food products where they become organoleptically undesirable [1]. It is also worth noting that several toxicological problems resulting from the ingestion of food containing large amounts of BA have been described [2]. Although there is no specific legislation regarding BA content in many food products, it is generally assumed that they should not be allowed to accumulate [3–5]. Fermented foods are likely to contain high

levels of BA, mainly due to the decarboxylase activity of some lactic acid bacteria (LAB). BA are produced by the decarboxylation PF-4708671 clinical trial of a precursor amino acid by the enzymatic action of an amino acid decarboxylase [6, 7]. In these selleck inhibitor foods, the main BA are tyramine, histamine, cadaverine and putrescine, which are produced by decarboxylation of tyrosine, histidine, lysine and ornithine, respectively [8]. The presence of the genes encoding the amino acid decarboxylase and the amino acid-amine antiporter is a general feature

observed in all the gene clusters involved in the biosynthesis of tyramine, histamine, putrescine and cadaverine [9–12]. We have found an open reading frame coding for a protein of 418 amino acids with a molar mass of 47.38 kDa located next to the tyrosine decarboxylase (tdcA) and the tyrosine-tyramine antiporter (tyrP) genes of Enterococcus durans IPLA655. The predicted amino acid sequence shares strong similarity to the tyrosyl-tRNA synthetase genes (tyrS) of gram positive bacteria. The aminoacyl-tRNA synthetases catalyze the covalent attachment of amino acids to their cognate tRNAs, a crucial reaction for the accuracy of protein synthesis. These enzymes are encoded by genes regulated strictly by antitermination systems; when the corresponding amino acid, tyrosine in this case, is at low concentration, it is not linked to the tRNA, and this uncharged tRNA interact with the antiterminator located between the promoter and the start codon, stabilizing it and allowing transcription. By contrast, when tyrosine is at high concentration, it is linked to the corresponding tRNA (charged tRNA) that cannot stabilize the antiterminator, and consequently the transcription stops [13].

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