Nitrate respiratory

Beryllium Nitrate Respiratory protection, gloves, clean clothes, chemical safety goggles. Move to fresh air, chest x-ray should be taken immediately to detect pneumonitis. Cuts or puncture wounds in which beryllium may be imbedded must be flushed with water for at least 15 minutes. Flush with water for at least 15 minutes and get medical attention. 

The large difference in the mortality from respiratory and heart disease may have a simple explanation. Ammonium nitrate is explosive and the fertilizer workers were probably not allowed to smoke at work. 

The oxides of nitrogen are somewhat sol in w, reacting with it in the presence of oxygen to form nitric and nitrous acids. This is the action that takes place deep in the respiratory system. The acids formed are irritants, causing congestion of the throat and bronchi, and edema of the lungs. The acids are neutralized by the alkalies present in the tissues, with the formation of nitrates and nitrites. The latter may cause some arterial dilation, fall in blood press, headache and dizziness, and there may be some formation of methemoglobin. However, the nitrite effect is of secondary importance... 

Nitrate reductase (respiratory) (QH2 nitrate reductase) Glutamate synthase Aerobic bacteria NO3- + QH, NOf + q S[Fe,S,r [FesS ] " Mo-cofactor +GO 24,55... 

Sulfate reducers can use a wide range of terminal electron acceptors, and sulfate can be replaced by nitrate as a respiratory substrate. Molybdenum-containing enzymes have been discovered in SRB (also see later discussion) and, in particular, D. desulfuricans, grown in the presence of nitrate, generates a complex enzymatic system containing the following molybdenum enzymes (a) aldehyde oxidoreduc-tase (AOR), which reduces adehydes to carboxylic acids (b) formate dehydrogenase (FDH), which oxidizes formate to CO2 and (c) nitrate reductase (the first isolated from a SRB), which completes the enzy-... 

There are four different classes of nitrate reductases (234). The nitrate reductases from D. desulfuricans show a strong homology to the a-subunit of the class of periplasmic respiratory nitrate reductases, and also to some of the enzymes that are included on the class of cytoplasmic assimilatory nitrate reductases. Because of this fact, a proposal was made for a new class of monomeric NAP, which contains the minimal arrangement of metal centers to perform nitrate reduction one [4Fe-4S] cluster and a Mo bound to two MGD. 

Figure 18.2 Summary of respiratory energy flows. Foods ate converted into the reduced form of nicotinamide adenine dinucleotide (NADH), a strong reductant, which is the most reducing of the respiratory electron carriers (donors). Respiration can he based on a variety of terminal oxidants, such as O2, nitrate, or fumarate. Of those, O2 is the strongest, so that aerobic respiration extracts the largest amount of free energy from a given amount of food. In aerobic respiration, NADH is not oxidized directly by O2 rather, the reaction proceeds through intermediate electron carriers, such as the quinone/quinol couple and cytochrome c. The most efficient respiratory pathway is based on oxidation of ferrocytochrome c (Fe ) with O2 catalyzed by cytochrome c oxidase (CcO). Of the 550 mV difference between the standard potentials of c)Tochrome c and O2, CcO converts 450 mV into proton-motive force (see the text for further details).

Others oxotransferases) (2 pyranopterins bonded to Mo) (8-10 members) Nitrate reduction dissimilatory terminal respiratory oxidase Pyridoxal oxidase Xanthine dehydrogenases Pyrogallol transhydrolase Nitrate to nitrite... 

Physical characteristics of photosmog include a yellow-brown haze, which reduces visibility, and the presence of substances which irritate the respiratory tract and cause eye-watering. The yellowish color is owed to NO2, whilst the irritant substances include ozone, aliphatic aldehydes, and organic nitrates. The four conditions necessary before photosmog can develop are ... 

Nitrate reductase (NADH) [EC 1.6.6.1], also known as assimilatory nitrate reduetase, eatalyzes the reaction of NADH with nitrate to produee NAD+, nitrite, and water. This enzyme uses FAD or FMN, heme, and a molybdenum ion as eofaetors. (2) Nitrate reductase (NAD(P)H) [EC 1.6.6.2], also known as assimilatory nitrate reduetase, eatalyzes the reaetion of NAD(P)H with nitrate to produee NAD(P)+, nitrite, and water. This enzyme uses FAD or FMN, heme, and a molybdenum ion as eofaetors. (3) Nitrate reductase (NADPH) [EC 1.6.6.3] eatalyzes the reaetion of NADPH with nitrate to produee NADP+, nitrite, and water. This enzyme uses FAD, heme, and a molybdenum ion as cofactors. (4) Nitrate reduetase (eytoehrome) [EC 1.9.6.1] catalyzes the reaetion of nitrate with ferroeytochrome to produce nitrite and ferrieytoehrome. (5) Nitrate reductase (ac-eeptor) [EC 1.7.99.4], also known as respiratory nitrate... 

Anesthetized dogs given 50-250mg/kg intravenously immediately showed hypotension, arrest of gut activity, respiratory paralysis, hyperpnea, and moderate methemoglobinemia. Because death was produced with methe-moglobin levels of only 4%, -propyl nitrate intoxication may be caused in part by a direct action on vascular smooth muscle. (It has been noted that the oral toxicity of -propyl nitrate is very low compared with intravenously administered doses, in which mg/kg doses were lethal versus g/kg orally. )... 

Gn Pig = guinea pig Hemato = hematological LOAEL = lowest-observed-adverse-effect level Musc/skel = muscular/skeletal NOAEL = no-observed-adverse-effect level RBC = red blood cell Resp = respiratory TF4 = thorium tetraf1uoride ThN03 = thorium nitrate Th02 = thorium dioxide. 

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