Detection of nitrite degradation by Lactobacillus plantarum DMDL9010 through the anaerobic respiration electron transport chain using proteomic analysis

Abstract

This study aimed to investigate the mechanism of nitrite degradation by Lactobacillus plantarum DMDL9010 using the proteomic technology. The results showed that 0.276 g L‾¹ nitrite was degraded completely by L. plantarum DMDL9010 in 24 h. Nitrite was transported into the pericytoplasm by a two-component system. Reduced nicotinamide adenine dinucleotide (NADH) and flavin adenine dinucleotide-2 (FADH₂) were produced during metabolism via these pathways of phosphotransferase system, glycolysis/gluconeogenesis and citrate cycle. NADH and FADH₂ produced electrons catalysed by dehydrogenase. The electrons were transferred through the electron transport chain eventually to nitrite. Some molecules of nitrites gained electrons and were reduced to NH₃ by nitrite reductase. Then NH₃ from nitrite was converted into L-glutamine catalysed by glutamine synthetase, which was one of the ways to generate l-glutamine. This study can provide theoretical guidance to the research on the biological technique to reduce nitrite in food products.