【摘要】 乳酸菌是食品工业和人体肠道常见微生物，可促进强致癌物亚硝胺的合成，而其促进机制尚待揭示，严重制约了发酵食品安全的提升和益生菌产品的推广。该文考察植物乳杆菌（Lactobacillus plantarum）6A对二乙基亚硝胺（N-nitrosodiethylamnie,NDEA）促进作用在不同环境中的变化趋势，以转录组技术进一步探究促进作用的关键基因和形成途径，构建其机制网络。结果表明，NDEA胁迫L. plantarum 6A通过上调嘌呤核苷酸合成/代谢（关键基因purL、purK、purC、purB、purA）、核黄素合成/代谢（ribBA、ribH、ribE）、双组分系统途径（dltD、dltB、dltA）的基因表达，产生NDEA前体物，如富含氮元素的嘌呤、核黄素及丙氨酸，从而促进NDEA形成；还可能通过核黄素合成/代谢以及双组分系统途径间接催化亚硝化反应，加速NDEA的形成。更多还原

【Abstract】 Lactic acid bacteria are common microorganisms in the food industry and human intestinal flora,they can promote the synthesis of N-nitrosamines that are strong carcinogens,and the promotion mechanism is still unclear,which strongly restricts the improvement of fermented food safety and the promotion of probiotic products. The change trends of Lactobacillus plantarum(L. plantarum)6A in promoting N-nitrosodiethylamnie(NDEA)synthesis in different environments were investigated in this paper,and the crucial genes and forming pathways involved in the promotion were further investigated by transcriptome technology. The network of promotion mechanisms was constructed. The results showed that NDEA forced L. plantarum 6A to produce NDEA precursors and thus promote the synthesis of NDEA by up-regulating gene expressions of purine nucleotide synthesis/metabolism(key genes as purL,purK,purC,purB,and purA),riboflavin synthesis/metabolism(ribBA,ribH,and ribE),and two-component system pathways(dltD,dltB,and dltA),and the precursors included nitrogen-rich purines,riboflavin,and alanine. It might indirectly catalyze nitrosation through riboflavin synthesis/metabolism and two-component system pathways to accelerate the synthesis of NDEA.更多还原