A mutation leading to the total lack of nitrite reductase activity in Escherichia coli K 12

1978 ◽  
Vol 160 (2) ◽  
pp. 225-229 ◽  
Author(s):  
M. Chippaux ◽  
D. Giudici ◽  
A. Abou-Jaoudé ◽  
F. Casse ◽  
M. C. Pascal
Keyword(s):  
Escherichia Coli ◽  
Nitrite Reductase ◽  
Reductase Activity ◽  
Nitrite Reductase Activity ◽  
Total Lack ◽  
K 12

scholarly journals Effect of ruminal administration ofEscherichia coliwild type or a genetically modified strain with enhanced high nitrite reductase activity on methane emission and nitrate toxicity in nitrate-infused sheep

2005 ◽  
Vol 94 (5) ◽  
pp. 691-697 ◽  
Author(s):  
C. Sar ◽  
B. Mwenya ◽  
B. Pen ◽  
K. Takaura ◽  
R. Morikawa ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Body Weight ◽  
Single Dose ◽  
Methane Emission ◽  
Nitrite Reductase ◽  
Reductase Activity ◽  
Wild Type ◽  
E Coli ◽  
Reduction Activity ◽  
Nitrite Reductase Activity

The effects of two kinds ofEscherichia coli(E. coli) strain, wild-typeE. coliW3110 andE. colinir-Ptac, which has enhanced NO2reduction activity, on oral CH4emission and NO3toxicity in NO3-treated sheep were assessed in a respiratory hood system in a 4×6 Youden square design. NO3(1·3g NaNO3/kg0·75body weight) and/orE. colistrains were delivered into the rumen through a fistula as a single dose 30min after the morning meal.Escherichia colicells were inoculated for sheep to provide an initialE. colicell density of optical density at 660nm of 2, which corresponded to 2×1010cells/ml. The six treatments consisted of saline,E. coliW3110,E. colinir-Ptac, NO3, NO3plusE. coliW3110, and NO3plusE. colinir-Ptac. CH4emission from sheep was reduced by the inoculation ofE. coliW3110 orE. colinir-Ptac by 6% and 12%, respectively. NO3markedly inhibited CH4emission from sheep. Compared with sheep given NO3alone, the inoculation ofE. coliW3110 to NO3-infused sheep lessened ruminal and plasma toxic NO2accumulation and blood methaemoglobin production, while keeping ruminal methanogenesis low. Ruminal and plasma toxic NO2accumulation and blood methaemoglobin production in sheep were unaffected by the inoculation ofE. colinir-Ptac. These results suggest that ruminal methanogenesis may be reduced by the inoculation ofE. coliW3110 orE. colinir-Ptac. The inoculation ofE. coliW3110 may abate NO3toxicity when NO3is used to inhibit CH4emission from ruminants.

scholarly journals 0099. Nitrite reductase activity during sepsis

2014 ◽  
Vol 2 (S1) ◽  
Author(s):  
V Simon ◽  
A Dyson ◽  
M Minnion ◽  
M Feelisch ◽  
M Singer
Keyword(s):  
Nitrite Reductase ◽  
Reductase Activity ◽  
Nitrite Reductase Activity

scholarly journals Nitrite Reductase Activity in Engineered Azurin Variants

2016 ◽  
Vol 55 (9) ◽  
pp. 4233-4247 ◽  
Author(s):  
Steven M. Berry ◽  
Jacob N. Strange ◽  
Erika L. Bladholm ◽  
Balabhadra Khatiwada ◽  
Christine G. Hedstrom ◽  
...  
Keyword(s):  
Nitrite Reductase ◽  
Reductase Activity ◽  
Nitrite Reductase Activity

scholarly journals Increased nitrite reductase activity of fetal versus adult ovine hemoglobin

2009 ◽  
Vol 296 (2) ◽  
pp. H237-H246 ◽  
Author(s):  
Arlin B. Blood ◽  
Mauro Tiso ◽  
Shilpa T. Verma ◽  
Jennifer Lo ◽  
Mahesh S. Joshi ◽  
...  
Keyword(s):  
Nitrite Reductase ◽  
Chronic Hypoxia ◽  
Reductase Activity ◽  
Fetal Hemoglobin ◽  
Nitrite Reduction ◽  
No Production ◽  
Low Oxygen ◽  
Nitrite Reductase Activity ◽  
Adult Hemoglobin ◽  
Severe Ischemia

Growing evidence indicates that nitrite, NO2−, serves as a circulating reservoir of nitric oxide (NO) bioactivity that is activated during physiological and pathological hypoxia. One of the intravascular mechanisms for nitrite conversion to NO is a chemical nitrite reductase activity of deoxyhemoglobin. The rate of NO production from this reaction is increased when hemoglobin is in the R conformation. Because the mammalian fetus exists in a low-oxygen environment compared with the adult and is exposed to episodes of severe ischemia during the normal birthing process, and because fetal hemoglobin assumes the R conformation more readily than adult hemoglobin, we hypothesized that nitrite reduction to NO may be enhanced in the fetal circulation. We found that the reaction was faster for fetal than maternal hemoglobin or blood and that the reactions were fastest at 50–80% oxygen saturation, consistent with an R-state catalysis that is predominant for fetal hemoglobin. Nitrite concentrations were similar in blood taken from chronically instrumented normoxic ewes and their fetuses but were elevated in response to chronic hypoxia. The findings suggest an augmented nitrite reductase activity of fetal hemoglobin and that the production of nitrite may participate in the regulation of vascular NO homeostasis in the fetus.

scholarly journals Inhibition of tobacco nitrite reductase activity by expression of antisense RNA.

1992 ◽  
Vol 2 (4) ◽  
pp. 559-569 ◽  
Author(s):  
H Vaucheret ◽  
J Kronenberger ◽  
A Lepingle ◽  
F Vilaine ◽  
JP Boutin ◽  
...  
Keyword(s):  
Nitrite Reductase ◽  
Antisense Rna ◽  
Reductase Activity ◽  
Nitrite Reductase Activity

scholarly journals The human B12 trafficking protein CblC processes nitrocobalamin

2020 ◽  
Vol 295 (28) ◽  
pp. 9630-9640 ◽  
Author(s):  
Romila Mascarenhas ◽  
Zhu Li ◽  
Carmen Gherasim ◽  
Markus Ruetz ◽  
Ruma Banerjee
Keyword(s):  
Nitrite Reductase ◽  
Reductase Activity ◽  
Methylmalonic Aciduria ◽  
Axial Ligand ◽  
Vitamin B ◽  
Early Step ◽  
Trafficking Pathway ◽  
Nitrite Reductase Activity ◽  
Futile Cycling ◽  
Thiol Oxidase

In humans, cobalamin or vitamin B12 is delivered to two target enzymes via a complex intracellular trafficking pathway comprising transporters and chaperones. CblC (or MMACHC) is a processing chaperone that catalyzes an early step in this trafficking pathway. CblC removes the upper axial ligand of cobalamin derivatives, forming an intermediate in the pathway that is subsequently converted to the active cofactor derivatives. Mutations in the cblC gene lead to methylmalonic aciduria and homocystinuria. Here, we report that nitrosylcobalamin (NOCbl), which was developed as an antiproliferative reagent, and is purported to cause cell death by virtue of releasing nitric oxide, is highly unstable in air and is rapidly oxidized to nitrocobalamin (NO2Cbl). We demonstrate that CblC catalyzes the GSH-dependent denitration of NO2Cbl forming 5-coordinate cob(II)alamin, which had one of two fates. It could be oxidized to aquo-cob(III)alamin or enter a futile thiol oxidase cycle forming GSH disulfide. Arg-161 in the active site of CblC suppressed the NO2Cbl-dependent thiol oxidase activity, whereas the disease-associated R161G variant stabilized cob(II)alamin and promoted futile cycling. We also report that CblC exhibits nitrite reductase activity, converting cob(I)alamin and nitrite to NOCbl. Finally, the denitration activity of CblC supported cell proliferation in the presence of NO2Cbl, which can serve as a cobalamin source. The newly described nitrite reductase and denitration activities of CblC extend its catalytic versatility, adding to its known decyanation and dealkylation activities. In summary, upon exposure to air, NOCbl is rapidly converted to NO2Cbl, which is a substrate for the B12 trafficking enzyme CblC.

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