Laboratorio de Biotecnología Bacteriana, Instituto de Ciencia y Tecnología de Alimentos y Nutrición, ICTAN-CSIC, Madrid, Spain.
Crit Rev Food Sci Nutr. 2012;52(5):448-67. doi: 10.1080/10408398.2010.500545.
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.
酪胺中毒是由摄入含有高水平酪胺的食物引起的，酪胺是一种生物胺。任何含有游离酪氨酸的食物，如果使用卫生条件差和质量低的食物，或者如果食物受到温度滥用或延长储存时间的影响，都有可能形成酪胺。酪胺是通过酪氨酸脱羧酶（TDC）酶从食物中存在的细菌中衍生的酪氨酸脱羧作用生成的。细菌 TDC 仅在革兰氏阳性菌中被明确鉴定和特征化，特别是在乳酸菌中。几种乳酸菌中的依赖吡哆醛磷酸（PLP）的 TDC 编码基因（tyrDC）似乎被类似的遗传组织结构所包围，这表明它们是由单个移动遗传元件共同起源的。细菌 TDC 也能够将苯丙氨酸脱羧生成苯乙胺（PEA），另一种生物胺。参与酪胺生产的基因的分子知识已经导致了用于检测能够产生酪胺和 PEA 的细菌的分子方法的发展。这些快速简单的方法可用于分析细菌形成酪胺的能力，以评估食品中酪胺生物合成的潜在风险。
