biology

Nitrite reductase (NO-forming)

Nitrite reductase (NO-forming) is a biology topic covered in the lgStudy science library. This page brings together a partial reference excerpt, illustrations, worked examples, real-world applications and a short study plan, so you can understand Nitrite reductase (NO-forming) rather than just read about it. In short: In enzymology, a nitrite reductase (NO-forming) (EC 1.7.2.1) is an enzyme that catalyzes the chemical reaction nitric oxide + H2O + ferricytochrome c ⇌ nitrite + ferrocytochrome c + 2 H+ The 3 substrates of this enzyme are nitric oxide, H2O, and ferricytochrome c, whereas its 3 products are nitrite, ferrocytochrome c, and H+. This enzyme belongs to the family of oxidoreductases, specifically those acting on other ni…

Key takeaways

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Reference excerpt

In enzymology, a nitrite reductase (NO-forming) (EC 1.7.2.1) is an enzyme that catalyzes the chemical reaction

nitric oxide + H2O + ferricytochrome c ⇌ nitrite + ferrocytochrome c + 2 H+ The 3 substrates of this enzyme are nitric oxide, H2O, and ferricytochrome c, whereas its 3 products are nitrite, ferrocytochrome c, and H+. This enzyme belongs to the family of oxidoreductases, specifically those acting on other nitrogenous compounds as donors with a cytochrome as acceptor. The systematic name of this enzyme class is nitric-oxide:ferricytochrome-c oxidoreductase. Other names in common use include cd-cytochrome nitrite reductase, [nitrite reductase (cytochrome)] [misleading, see comments.], cytochrome c-551:O2, NO2+ oxidoreductase, cytochrome cd, cytochrome cd1, hydroxylamine (acceptor) reductase, methyl viologen-nitrite reductase, nitrite reductase (cytochrome, and NO-forming). This enzyme participates in nitrogen metabolism. It has 3 cofactors: FAD, Iron, and Copper.

Structural studies As of late 2007, 20 structures have been solved for this class of enzymes, with PDB accession codes PDB: 1RZP, PDB: 1RZQ, PDB: 1SJM, PDB: 1SNR, PDB: 1ZDQ, PDB: 1ZDS, PDB: 1ZV2, PDB: 2A3T, PDB: 2AVF, PDB: 2B08, PDB: 2BW4, PDB: 2BW5, PDB: 2BWD, PDB: 2BWI, PDB: 2DV6, PDB: 2DWS, PDB: 2DWT, PDB: 2DY2, PDB: 2FJS, and PDB: 2JFC.

References

Miyata M, Mori T (October 1969). "Studies on denitrification. X. The "denitrifying enzyme" as a nitrite reductase and the electron donating system for denitrification". J. Biochem. 66 (4). Tokyo: 463–471. doi:10.1093/oxfordjournals.jbchem.a129170. PMID 5354021. CHUNG CW, NAJJAR VA (1956). "Cofactor requirements for enzymatic denitrification. I. Nitrite reductase". J. Biol. Chem. 218 (2): 617–625. doi:10.1016/S0021-9258(18)65827-2. PMID 13295215. Walker GC, Nicholas DJ (1961). "Nitrite reductase from Pseudomonas aeruginosa". Biochim. Biophys. Acta. 49 (2): 350–360. doi:10.1016/0006-3002(61)90134-2. PMID 13782716. Singh J (1974). "Cytochrome oxidase from Pseudomonas aeruginosa. III. Reduction of hydroxylamine". Biochim. Biophys. Acta. 333 (1): 28–36. doi:10.1016/0005-2728(74)90159-5. PMID 19396990. Michalski WP, Nicholas DJ (1985). "Molecular characterization of a copper-containing nitrite reductase from Rhodopseudomonas sphaeriodes forma sp. Denitrificans". Biochim. Biophys. Acta. 828 (2): 130–137. doi:10.1016/0167-4838(85)90048-2. Godden JW; Turley, S; Teller, DC; Adman, ET; Liu, MY; Payne, WJ; Legall, J (1991). "The 2.3 angstrom X-ray structure of nitrite reductase from Achromobacter cycloclastes". Science. 253 (5018): 438–442. Bibcode:1991Sci...253..438G. doi:10.1126/science.1862344. PMID 1862344. Williams PA, Fülöp V, Leung YC, Chan C, Moir JW, Howlett G, Ferguson SJ, Radford SE, Hajdu J (1995). "Pseudospecific docking surfaces on electron transfer proteins as illustrated by pseudoazurin, cytochrome c550 and cytochrome cd1 nitrite reductase". Nat. Struct. Biol. 2 (11): 975–982. doi:10.1038/nsb1195-975. PMID 7583671. S2CID 21798842. B, Kroneck PM; Vollack, KU; Zumft, WG; Eisenmann, E; Siddiqui, RA; Friedrich, B; Kroneck, PM (1996). "Characterization of the membranous denitrification enzymes nitrite reductase (cytochrome cd1) and copper-containing nitrous oxide reductase from Thiobacillus denitrificans". Arch. Microbiol. 165 (1): 55–61. Bibcode:1996ArMic.165...55H. doi:10.1007/s002030050296. PMID 8639023. S2CID 12737971. Zumft WG (1997). "Cell biology and molecular basis of denitrification". Microbiol. Mol. Biol. Rev. 61 (4): 533–616. doi:10.1128/mmbr.61.4.533-616.1997. PMC 232623. PMID 9409151. Ferguson SJ (1998). "Nitrogen cycle enzymology". Curr. Opin. Chem. Biol. 2 (2): 182–193. doi:10.1016/S1367-5931(98)80059-8. PMID 9667932. Vijgenboom E, Busch JE, Canters GW (September 1997). "In vivo studies disprove an obligatory role of azurin in denitrification in Pseudomonas aeruginosa and show that azu expression is under control of rpoS and ANR". Microbiology. 143 (9): 2853–2863. doi:10.1099/00221287-143-9-2853. hdl:1887/3239420. PMID 9308169.

Illustrations

Worked examples

Example 1 — a first encounter with Nitrite reductase (NO-forming)

Start with the simplest possible case. Write down what Nitrite reductase (NO-forming) claims or describes in one sentence, then invent the smallest concrete situation in which that sentence is true. In biology, the smallest case is usually a single object, a single equation or a single measurement. Check that every symbol or term in your sentence has a meaning in that case.

Example 2 — changing one variable

Take the situation from Example 1 and change exactly one quantity: double it, halve it, or set it to zero. Predict what should happen to Nitrite reductase (NO-forming) before you calculate. Comparing your prediction with the result is the fastest way to find out whether you understand the idea or only the words.

Example 3 — an exam-style question

Typical questions about Nitrite reductase (NO-forming) ask you to (a) state it precisely, (b) apply it to given data, and (c) explain a limitation. Practise writing all three answers in under five minutes; the third part is what separates a full-mark answer from an average one.

Applications of Nitrite reductase (NO-forming)

In research: Nitrite reductase (NO-forming) appears in biology research whenever the underlying quantities have to be modelled precisely. Papers usually cite it as a starting assumption and then explore where it breaks down.
In technology and industry: Engineering practice reuses Nitrite reductase (NO-forming) in design rules, simulations and safety margins. Knowing the idea lets you read a specification sheet and understand why the numbers look the way they do.
In the classroom: Nitrite reductase (NO-forming) is common in secondary-school and first-year university syllabi. It links to neighbouring topics Copper enzymes, EC 1.7.2, Enzymes of known structure, so understanding it makes those chapters shorter.
In everyday life: Look for Nitrite reductase (NO-forming) outside the textbook — in sport, cooking, traffic, electronics or the sky above you. An example you found yourself is remembered far longer than one you were given.

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Frequently asked questions

What is Nitrite reductase (NO-forming) in simple terms?

In enzymology, a nitrite reductase (NO-forming) (EC 1.7.2.1) is an enzyme that catalyzes the chemical reaction nitric oxide + H2O + ferricytochrome c ⇌ nitrite + ferrocytochrome c + 2 H+ The 3 substrates of this enzyme are nitric oxide, H2O, and ferricytochrome c, whereas its 3 products are nitrite…

Why does Nitrite reductase (NO-forming) matter?

Because it connects several biology ideas at once: it gives you a definition you can apply, a quantity you can calculate, and a way to check whether a result is plausible.

How should I study Nitrite reductase (NO-forming)?

Read the excerpt, restate it from memory, then work through the examples and applications listed on this page. The five-step study plan above takes about twenty minutes.

What does this page cover?

It gives you a compact reference excerpt plus original lgStudy explanations, examples, applications and study material on Nitrite reductase (NO-forming).