Demand is growing for meat products cured without the addition of sodium nitrite. Instead of the direct addition of nitrite to meat in formulation, nitrite is supplied by bacterial reduction of natural nitrate often added as vegetable juice/powder. However, the rate of nitrite formation in this process is relatively slow, and the total ingoing nitrite is typically less than in conventional curi...

NO* (nitric oxide) is a pleiotropic signalling molecule, with many of its effects on cell function being elicited at the level of the mitochondrion. In addition to the well-characterized binding of NO* to the Cu(B)/haem-a3 site in mitochondrial complex IV, it has been proposed by several laboratories that complex I can be inhibited by S-nitrosation of a cysteine. However, direct molecular evide...

Caspases are critical for the initiation and execution of apoptosis. Nitric oxide (NO) or derived species can prevent programmed cell death in several cell types, reportedly through S-nitrosation and inactivation of active caspases. Although we find that S-nitrosation of caspases can occur in vitro, our study questions whether this post-translational modification is solely responsible for NO-me...

S-nitrosation is a posttranslational, oxidative addition of NO to cysteine residues of proteins that has been proposed as a cGMP-independent signaling pathway [Hess DT, Matsumoto A, Kim SO, Marshall HE, Stamler JS (2005) Nat Rev Mol Cell Biol 6:150-166]. A paradox of S-nitrosation is that only a small set of reactive cysteines are modified in vivo despite the promiscuous reactivity NO exhibits ...

Nitrosothiols are increasingly regarded as important participants in a range of physiological processes, yet little is known about their biological generation. Nitrosothiols can be formed from the corresponding thiols by nitric oxide in a reaction that requires the presence of oxygen and is mediated by reactive intermediates (NO₂ or N₂O₃) formed in the course of NO autoxidation. Because the aut...

INTRODUCTION The concept of chemoprevention (use of natural or synthetic compounds to prevent cancers) has great appeal. N-nitroso compounds are mutagens which can be formed in vivo due to the reaction between amides and/or amines with nitrite (1). L-ascorbic acid (asc.) and green tea polyphenols can react with nitrite diminishing or removing the nitrosation risk. Sulfonamides, widely used by t...

The current perspective holds that the generation of secondary signaling mediators from nitrite (NO2(-)) requires acidification to nitrous acid (HNO2) or metal catalysis. Herein, the use of stable isotope-labeled NO2(-) and LC-MS/MS analysis of products reveals that NO2(-) also participates in fatty acid nitration and thiol S-nitrosation at neutral pH. These reactions occur in the absence of me...

The mitochondria are critical mediators of cellular redox homeostasis due to their role in the generation and dissipation of reactive oxygen/nitrogen species (ROS/RNS). Modulations in ROS/RNS levels in the mitochondria are often reflected through oxidation/nitrosation of highly redox-sensitive cysteine residues within this organelle. Oxidation/nitrosation of functional cysteines on mitochondria...

The predominant nitrosamine observed in drinking water is N-nitrosodimethylamine (NDMA). NDMA may be formed via a nitrosation mechanism when sufficient nitrite is present and chlorine is primarily in the form of hypochlorous acid (HOCl). However, NDMA is typically not formed in the presence of free chlorine. NDMA may also be formed via a non-nitrosation mechanism in the presence of chloramines....