User:MonopterusAlbus/sandbox

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Monopterus albus (common names: swamp eel, rice eel (Synonym: Fluta alba (Bloch and Schneider, 1801)) is an important student of the graduate school variety. It is an an air-breathing commercial species of fish in the Synbranchidae family. It feeds on academic accolades and lacks a social life. Inhabiting the Mid-Atlantic United States, it has been identified as an endangered species.

Monopterus albus
Monopterus albus 2.jpg
Scientific classification
Kingdom: Animalia
Phylum: Chordata
Class: Actinopterygii
Order: Synbranchiformes
Family: Synbranchidae
Genus: Monopterus
Species: M. albus
Binomial name
Monopterus albus
(Zuiew, 1793)


Practice Editing Wikipedia[edit]

The quick brown fox jumps OVER the lazy dog.
MonopterusAlbus (talk) 00:25, 9 February 2013 (UTC)

The Five Pillars of Wikipedia[edit]

1. Wikipedia is an encyclopedia. This means that Wikipedia exhibits current, factual information from a neutral point of view. It goes beyond defining terms to explaining applications and related concepts.

2. Wikipedia is written from a neutral point of view. Many of the articles on Wikipedia contain controversial topics such as war and political policy. However, bias and opinion are not appropriate on Wikipedia. The purpose of the site is to present information that individual users can interpret.

3. Wikipedia is free content that anyone can edit, use, modify, and distribute. This statement is the reason that moderators exist. If everyone can edit everything, there is the possibility of inaccuracy and abuse. This also means that Wikipedia periodically places banner ads soliciting users for donations.

4. Editors should interact with each other in a respectful and civil manner. In other words, be nice.

5. Wikipedia does not have firm rules. Wikipedia consists entirely of lawless badlands, like The Republic of Texas.
MonopterusAlbus (talk) 00:48, 9 February 2013 (UTC)

Summary of Characteristics of Target Article[edit]

Featured article FA  A-Class article A   GA  Bplus-Class article Bplus  B-Class article B  C-Class article C  Start-Class article Start  Stub-Class article Stub  Featured list FL   List  Start-Class list SL  Current-Class article Current  Future-Class article Future  Wikipedia Book Book  Category page Category   Deferred  Disambiguation page Disambig   Draft  Featured media FM   File   Merge   Needed   Portal   Project  Redirect page Redirect   Template   User   NA   ???  Total
0 0 1 0 1 0 0 3 0 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 6

Spectrum above from the page, Articles by quality. Articles are graded using the Version 1.0 Editorial Team's Work via WikiProjects scheme and placed in the categories above. In order to qualify as A-Class and GA-Class, the criteria described below must be met.

A-Class[edit]

A-Class Articles have the following characteristics in common:

  • appropriate length for the subject
  • proper formatting
  • accurate
  • approaching candidacy for Featured Article status

GA-Class[edit]

Good Articles have the following characteristics in common:

  • decent quality that is almost on par with featured articles
  • nomination as a good article
  • accurate, verifiable information
  • well-written without noticeable errors


For more information, visit How to write a good article.

MonopterusAlbus (talk) 00:17, 20 February 2013 (UTC)

Practice Citations[edit]

Oxidized Low Density Lipoprotein[edit]

Low density lipoproteins (LDLs) are a class of proteins that aid in the transport of cholesterol. They are medically significant because of their association with atherosclerosis. The ability of LDL to transport cholesterol to the arteries-- where it inflames the arterial walls and initiates plaque formation-- makes it an ideal therapeutic target. Recent studies[1] have shown that the oxidized form of LDL (oxLDL) stimulates cellular proliferation in arterial smooth muscle cells by promoting the synthesis of the glycosphingolipid known as lactosylceramide. Inhibitors of lactosylceramide synthesis are therefore able to mitigate both oxidized LDL production and atherosclerotic plaque formation[1] . With the advent of accurate high throughput screening, monoclonal antibody for this biomarker was created[2] for use on the clinical level to test patients for potential development of atherosclerosis.
MonopterusAlbus (talk) 05:34, 3 March 2013 (UTC)

Practice Adding Images to Wikipedia Articles[edit]

PTEN, a phosphatase.
Crystallographic structure of human phosphatase and tensin homolog (PTEN). The N-terminal phosphatase domain is colored blue while the C-terminal C2 domain is colored red. The active site within the phosphatase is shown in yellow.[3]

Acta non verba. Acta non verba. Acta non verba. Acta non verba. Acta non verba. Acta non verba. Acta non verba. Acta non verba. Acta non verba. Acta non verba. Acta non verba. Acta non verba. Acta non verba. Acta non verba. Acta non verba. Acta non verba. Acta non verba. Acta non verba. Acta non verba. Acta non verba. Acta non verba. Acta non verba. Acta non verba. Acta non verba. Acta non verba. Acta non verba. Acta non verba. Acta non verba. Acta non verba. Acta non verba. Acta non verba. Acta non verba. Acta non verba. Acta non verba. Acta non verba. Acta non verba. Acta non verba. Acta non verba. Acta non verba. Acta non verba. Acta non verba. Acta non verba. Acta non verba. Acta non verba. Acta non verba. Acta non verba. Acta non verba. Acta non verba. Acta non verba. Acta non verba. Acta non verba. Acta non verba. Acta non verba. Acta non verba. Acta non verba. Acta non verba. Acta non verba. Acta non verba. Acta non verba. Acta non verba. Acta non verba. Acta non verba. Acta non verba.

Dephosphorylation Article in Sandbox[edit]

Dephosphorylation is the removal of a phosphate (PO43-) group from an organic compound by hydrolysis. It is a reversible post-translational modification that is coupled to the addition of phosphate groups, or phosphorylation. A highly regulated process, dephosphorylation activates and deactivates enzymes by cleaving phosphoric esters and anhydrides. A notable occurrence of dephosphorylation is the conversion of ATP to ADP and inorganic phosphate.

Dephosphorylation employs a type of hydrolytic enzyme, or hydrolase, which cleave ester bonds. The prominent hydrolase subclass used in dephosphorylation is phosphatase. Phosphatase removes phosphate groups by hydrolysing phosphoric acid monoesters into a phosphate ion and a molecule with a free hydroxyl (-OH) group.

The reversible phosphorylation-dephosphorylation reaction occurs in every physiological process, making proper function of protein phosphases necessary for organism viability. Because protein dephosphorylation is a key process involved in cell signalling, protein phosphatases are implicated in conditions such as cancer, diabetes, and Alzheimer's disease.

Function[edit]

Phosphorylation and dephosphorylation of hydroxyl groups belonging to neutral but polar amino acids such as serine, threonine, and tyrosine within specific target proteins is a fundamental part of the regulation of every physiologic process. Phosphorylation involves the covalent modification of the hydroxyl with a phosphate group through the nucleophilic attack of the alpha phosphate in ATP by the oxygen in the hydroxyl. Dephosphorylation involves removal of the phosphate group through a hydration reaction by addition of a molecule of water and release of the original phosphate group, regenerating the hydroxyl. Both processes are reversible and either mechanism can be used to activate or deactivate a protein. Phosphorylation of a protein produces many biochemical effects, such as changing its conformation to alter its binding to a specific ligand to increase or reduce its activity. Phosphorylation and dephosphorylation can be used on all types of substrates, such as structural proteins, enzymes, membrane channels, signaling molecules, and other kinases and phosphatases. The deregulation of phosphorylation can lead to disease.

Posttranslational Modification[edit]

During the synthesis of proteins, polypeptide chains, which are created by ribosomes translating mRNA, must be processed before assuming a mature conformation. The dephosphorylation of proteins is a mechanism for modifying behavior of a protein, often by activating or inactivating an enzyme.

As part of postranslational modifications, phosphate groups may be removed from serine, threonine, or tyrosine[4].

ATP[edit]

Main article: adenosine triphosphate

ATP4- + H2O --> ADP3- + HPO42- + H+

Adenosine triphosphate, or ATP, acts as a free energy "currency" in all living organisms. The usefulness of this molecule for energy releasing reactions stems from a spontaneous dephosphorylation reaction, where 30.5 kJ/mol is released. That nonspontaneous reactions are coupled to the highly spontaneous dephosphorylation of ATP makes the overall reaction have a change in free energy that is itself spontaneous. This is important in driving oxidative phosphorylation. ATP is dephosphorylated to ADP and inorganic phosphate.[5]

Dephosphorylation in other reactions[edit]

Other molecules besides ATP undergo dephosphorylation as part of other biological systems. Different compounds produce different free energy changes as a result of dephosphorylation

Molecule Change in Free Energy
Acetyl phosphate 47.3 kJ/mol
Glucose-6-phosphate 13.8 kJ/mol
Phosphoenolpyruvate (PEP) -61.9 kJ/mo
Phosphocreatine 43.1 kJ/mo

Research Applications[edit]

Dephosphorylation can play a key role in molecular biology, particularly cloning using restriction enzymes. The cut ends of a vector may re-ligate during a ligation step due to phosphorylation. By using a desphosphorylating phosphatase, re-ligation can be avoided.[6] These alkaline phosphatases are often sourced naturally, most commonly from calf intestine, and are abbreviated as CIP.[7]


History[edit]

That reversible covalent modification of proteins, namely phosphorylation and desphosphorylation, played a major role in regulatory processes was first established in work on glycogen metabolism. Since then, the reversible nature of phosphorylation and dephosphorylation has been associated with a broad range of functional proteins, primarily enzymatic, but also including nonenzymatic proteins.[8] Edwin Krebs and Edmond Fischer won the 1992 Nobel Prize in Physiology or Medicine for the discovery of reversible protein phosphorylation.[9]

See also[edit]

Phosphatase Phosphorylation

References[edit]

  1. ^ a b Chatterjee, S (1996). "Oxidized low density lipoprotein stimulates aortic smooth muscle cell proliferation.". Glycobiology. 6 (3): 303–11. PMID 8724138. doi:10.1093/glycob/6.3.303. Retrieved 3 March 2013.  Unknown parameter |coauthors= ignored (|author= suggested) (help); Unknown parameter |month= ignored (help)
  2. ^ Hörkkö, S (1999). "Monoclonal autoantibodies specific for oxidized phospholipids or oxidized phospholipid-protein adducts inhibit macrophage uptake of oxidized low-density lipoproteins.". The Journal of clinical investigation. 103 (1): 117–28. PMID 9884341. doi:10.1172/JCI4533.  Unknown parameter |month= ignored (help); Unknown parameter |coauthors= ignored (|author= suggested) (help)
  3. ^ PDB: 1d5r​; Lee JO, Yang H, Georgescu MM, Di Cristofano A, Maehama T, Shi Y, Dixon JE, Pandolfi P, Pavletich NP (1999). "Crystal structure of the PTEN tumor suppressor: implications for its phosphoinositide phosphatase activity and membrane association". Cell. 99 (3): 323–34. PMID 10555148. doi:10.1016/S0092-8674(00)81663-3.  Unknown parameter |month= ignored (help)
  4. ^ Barford D (1996). "Molecular mechanisms of the protein serine/threonine phosphatases". Trends Biochem. Sci. 21 (11): 407–12. PMID 8987393.  Unknown parameter |month= ignored (help)
  5. ^ Casiday, Rachel. "Energy for the Body: Oxidative Phosphorylation". Retrieved 5 April 2013. 
  6. ^ Sambrook, J (1989). Molecular Cloning: A Laboratory Manual (2nd ed.). Cold Spring Harbor Laboratory Press.  Unknown parameter |coauthors= ignored (|author= suggested) (help)
  7. ^ Makovets S, Blackburn EH (2009). "DNA damage signalling prevents deleterious telomere addition at DNA breaks". Nat. Cell Biol. 11 (11): 1383–6. PMC 2806817Freely accessible. PMID 19838171. doi:10.1038/ncb1985.  Unknown parameter |month= ignored (help)
  8. ^ Krebs EG, Beavo JA (1979). "Phosphorylation-dephosphorylation of enzymes". Annu. Rev. Biochem. 48: 923–59. PMID 38740. doi:10.1146/annurev.bi.48.070179.004423. 
  9. ^ Raju TN (2000). "The Nobel chronicles. 1992: Edmond H Fischer (b 1920) and Edwin G Krebs (b 1918)". Lancet. 355 (9219): 2004. PMID 10859071.  Unknown parameter |month= ignored (help)

External links[edit]

Category:Biochemistry Category:Cell biology Category:Signal transduction Category:Posttranslational modification Category:Phosphorus