title: Tyramine and phenylethylamine biosynthesis by food bacteria.
abstract: Tyramine poisoning is caused by the ingestion of food containing high levels of tyramine, a biogenic amine. Any foods containing free tyrosine are subject to tyramine formation if poor sanitation and low quality foods are used or if the food is subject to temperature abuse or extended storage time. Tyramine is generated by decarboxylation of the tyrosine through tyrosine decarboxylase (TDC) enzymes derived from the bacteria present in the food. Bacterial TDC have been only unequivocally identified and characterized in Gram-positive bacteria, especially in lactic acid bacteria. Pyridoxal phosphate (PLP)-dependent TDC encoding genes (tyrDC) appeared flanked by a similar genetic organization in several species of lactic acid bacteria, suggesting a common origin by a single mobile genetic element. Bacterial TDC are also able to decarboxylate phenylalanine to produce phenylethylamine (PEA), another biogenic amine. The molecular knowledge of the genes involved in tyramine production has led to the development of molecular methods for the detection of bacteria able to produce tyramine and PEA. These rapid and simple methods could be used for the analysis of the ability to form tyramine by bacteria in order to evaluate the potential risk of tyramine biosynthesis in food products.
authors.affiliation: Laboratorio de Biotecnología Bacteriana, Instituto de Ciencia y Tecnología de Alimentos y Nutrición, ICTAN-CSIC, Madrid, Spain.
authors.forename: Angela
authors.initials: A
authors.lastname: Marcobal
authors.forename: Blanca
authors.initials: B
authors.lastname: De las Rivas
authors.forename: José María
authors.initials: JM
authors.lastname: Landete
authors.forename: Laura
authors.initials: L
authors.lastname: Tabera
authors.forename: Rosario
authors.initials: R
authors.lastname: Muñoz
mesh_terms: D018759:Adrenergic Uptake Inhibitors / Q000009:adverse effects / Q000378:metabolism*; D001142:Aromatic-L-Amino-Acid Decarboxylases / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D001426:Bacterial Proteins / Q000737:chemistry / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*; D015373:Bacterial Typing Techniques; D005513:Food Inspection / Q000379:methods; D005516:Food Microbiology; D006090:Gram-Negative Bacteria / Q000201:enzymology; D006094:Gram-Positive Bacteria / Q000201:enzymology; D010627:Phenethylamines / Q000009:adverse effects / Q000378:metabolism*; D014439:Tyramine / Q000009:adverse effects / Q000378:metabolism*; D014445:Tyrosine Decarboxylase / Q000737:chemistry / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*; D014662:Vasoconstrictor Agents / Q000009:adverse effects / Q000378:metabolism*
chemical_list: D018759:Adrenergic Uptake Inhibitors; D001426:Bacterial Proteins; D010627:Phenethylamines; D014662:Vasoconstrictor Agents; C029261:phenethylamine; D014445:Tyrosine Decarboxylase; D001142:Aromatic-L-Amino-Acid Decarboxylases; D014439:Tyramine