|WikiProject Molecular and Cell Biology||(Rated B-class, High-importance)|
- 1 distribution
- 2 difference between peroxidases and catalase
- 3 5 Million? 30,000,000? Both? Neither?
- 4 Protection
- 5 Catalase test
- 6 optimum temperature for catalase activity
- 7 The first sentence after the "Role in organs"
- 8 Could you list every cell that has catalase in it?
- 9 Catalytic Strategies of Catalase
- 10 Dead link
- 11 Split
- 12 I found a new article for you folks
- 13 Catalase, Streptococci and Enterococci
- 14 Catalase and the Bombardier Beetles
- 15 Food sources of Catalase?
- 16 Iron becomes oxygen?
- 17 Empirical Formula?
- 18 "Human catalase works at an optimum temperature of 45 °C" not comfirmed in source
- 19 External links modified
The article suggests that erytrocyte catalase is catalase; at the same time catalase is said to be localized to peroxisomes; erytrocytes do not have peroxisomes, however. Will intoduce "e.g." and "usually" until someone distinguishes ery / cytosolic / peroxisome catalase ...
I would like to know which living creature produces most catalase and water in its life span and which produces more water than it consumes. Thank you.
What's the main difference between peroxidases and catalase?
difference between peroxidases and catalase
Catalase is unique in its potential to catalyse 2 reactions: i) decomposition of hydrogen peroxide into water and oxygen; ii) oxidation of a substrate (hydrogen donor) with the help of hydrogen peroxide. Hydrogen donors for catalase are ethanol (drink alcohol), methanol, and laboratory reagents that are used to demonstrate the peroxidatic activity of the enzyme. Best known among the latter is diaminobenzidine, which forms an insoluble polymer that is brown when oxidized. Since it is insoluble, it precipitates exactly where catalase is localized, and thus shows in the microscope the exact location of the enzyme in the cell. This stain which is very reliable if carried out correctly, has been used by many investigators to identify and study the peroxisomes, since these organelles in normal conditions contain a lot of catalase. Peroxidases can carry out only the second kind of reaction, that is: oxidizing a hydrogen donor. Many of them can be localized with diaminobenzidine too. There are many different peroxidases, that is their pH optimum, resistance to chemicals and temperature differ. However some peroxidases have very specific substrates, for example glutathione (GSH) peroxidase does not react with diaminobenzidine; it protects the cell against hydrogen peroxide but destroy GSH that must be regenerated at the expense of energy. Another specific peroxidase is found in the thyroid epithelial cell: it binds iodium to thyreoglobuline, and this reaction results in the active thyroid hormone. Peroxidases are found in milk (lactoperoxidase), saliva (probably also lactoperoxidase), tears (lacrimal gland), in granular leucocytes (myeloperoxidase and eosinophil peroxidase), macrophages, blood platelets, uterine epithelium, and many other cell types. The best known plant peroxidase is horseradish peroxidase (HRP) that is a common laboratory reagent; when coupled to antibodies, these are subsequenlty demonstrated and localized through a peroxidatic reaction (with diaminobenzidine, for ex). Frank Roels, August 25th, 2005.
5 Million? 30,000,000? Both? Neither?
I've been researching catalase and keep coming up with conflicting figures. Everyone says "it's one of the most efficient enzymes," but after that, numbers diverge. In this article alone, it is purported to "convert 5 million molecules of hydrogen peroxide to water and oxygen each minute" and "500,000/second." Which is it? Are the numbers refering to two different things, maybe? If so, can we clarify that in the article a little better? Also, sources?
Thanks for your time.
This page quotes M.B.V. Roberts, author of "Biology A Functional Approach" as saying that catalase has a turnover number of 6 million/min
Kb ganesh 18:18, 29 August 2006 (UTC)
- I think part of the problem is that there are different kinds of catalase. Another problem is that the rate of reaction is heavily influenced by the conditions in which it occurs. I'll work on making this clear in the article. Galanskov 01:57, 12 February 2007 (UTC)
- First, do the math: 500,000/sec only three times 5,000,000/min. So they're not that different, on the sort of scale we're talking about. Enzyme efficiency also depends upon environmental factors. In other words, it's a rough estimate. Fearwig 08:48, 10 August 2007 (UTC)
- 500,000/sec is actually six times 5,000,000/min. And that isn't "not that different", it's actually quite a lot. It's true they're on a big scale.. but having differences of up to 6 times bigger is still a lot. - Draygen 19:43, 9 February 2009 (UTC)
Please semiprotect this page. It has been a target of vandalism by someone by the IP 22.214.171.124. --Gray Porpoise 17:26, 28 June 2006 (UTC)
I agree in Semi-protecting this page, according to the history, it has been vandalize multiple times in the past until currently. I believe it is reasonable enough to do so... Rave1112 (talk) 03:22, 17 December 2008 (UTC)
The catalase test bit doesn't really explain what it's for very well. A biologist of any calling will probably have no problem guessing what it's for with the info currently given but someone else might go, what the heck? Nil Einne 14:37, 11 October 2006 (UTC)
- It is also apparent that the Action of Catalase and Catalase Test (under Human application) say the same exact thing. This should be rectified, but I don't have the time nor the knowledge to do so. Helixer (talk) 02:29, 25 November 2008 (UTC)
optimum temperature for catalase activity
I would like to know the temperature at which catalase activity is optimized. Is it significantly different for human catalase as opposed to the catalase found in bovines? —The preceding unsigned comment was added by 126.96.36.199 (talk) 05:33, 12 December 2006 (UTC).
The first sentence after the "Role in organs"
This sentence used to be: Hydrogen peroxide is formed as a waste product of metabolism in many living organisms It is now: Hydrogen peroxide is not as a neverof metabolism in many dead organisms. I believe that the previous edition is correct, but I don't know much about biology. Maybe the editor didn't know much english. —The preceding unsigned comment was added by 188.8.131.52 (talk) 00:27, 13 December 2006 (UTC).
I noticed that, and im wondering if we should change it back, the change looks like vandalisation to me Atlasrune 18:10, 15 December 2006 (UTC) Yes it most definetly is vandalism--Max Randor 19:40, 1 February 2007 (UTC) already has been fixed --Max Randor 19:42, 1 February 2007 (UTC)
Could you list every cell that has catalase in it?
Is it clear the number of cells that have catalase in it? I think people come out of microbiology after they learn about staph aureus and the catalase test used to distinguish it and think that it is one of the few "cells" organisms that have catalase and maybe it should be emphasized more that a lot of cells have catalase in them. An exhaustive list would be cool but maybe impossible (?). —The preceding unsigned comment was added by 184.108.40.206 (talk) 22:41, 28 January 2007 (UTC).
- The article actually makes it sound as though almost every organism has catalase in it, which is dead wrong. There are a wide variety of bacteria (aerobic and anaerobic) that don't, and contrary to what the article says, there are a lot of fungi (especially higher fungi) that apparently do. Otherwise, peroxide would be an absolutely rotten sanitizer, which it isn't. Unless I'm misunderstanding something, that is. Fearwig 08:52, 10 August 2007 (UTC)
Catalytic Strategies of Catalase
I can't find any information to add about the catalytic strategy of catalase, and I believe this is important. Hopefully someone can tell me HOW catalase reduces the activation energy of (what?) This info seems to be non-existent.
As soon as I get the chance I'd like to add the source:
Vetrano, Anna M., et al. "Characterization of the Oxidase Activity in Mammalian Catalase." The Journal of biological chemistry 280.42 (2005):35372-.
The catalase FAQ link is dead. should it be removed? soldierx40k 20:41, 29 September 2007 (UTC)
I went ahead and removed it. No need to leave a dead link.Artephius (talk) 16:05, 13 August 2008 (UTC)
Also note, that the catylase test reference links are dead - ref 3,4,5. (there maybe more dead links, but i havent tested them). —Preceding unsigned comment added by Jubalj (talk • contribs) 17:09, 1 September 2008 (UTC)
This article tries to do too much. It should be split into a main page with a treatment of catalases (which I believe are not all homologs) and the known catalases from the various organisms. AnteaterZot (talk) 00:14, 6 February 2008 (UTC)
- This page is short compared to many Wikipedia pages. Granted, it's not a stub, but if you broke it into to pages, then each one would be. And what do you mean by "treatment" of catalases? Furthermore, I don't think there is more than one kind of catalase. Heck, my spell-check says catalases isn't a word! PhishRCool Talk / Contribs / Secret Page 21:47, 20 October 2008 (UTC)
- I am studying for Step 2 of the US Medical Licensing Exam right now, and this article seems just right to me.Niels Olson (talk) 00:39, 21 November 2008 (UTC)
I found a new article for you folks
Catalase, Streptococci and Enterococci
Many authors refer to both Streptococcus and Enterococcus species as being “aerobic bacteria” because of their ability to grow in the presence of oxygen. However, the species of those two genera do not use oxidative metabolism for their energetic needs. Instead, they are fermentative bacteria, and yes, the process of fermentation can occur in the presence of oxygen. Thus, more appropriate affiliation for Streptococcus and Enterococcus bacteria would be “oxygen-indifferent anaerobes”, which clearly indicates that they do not care if oxygen is present or not. They grow equally well in the presence or the absence of oxygen. By not using the oxygen (and therefore not having cytochrome oxidase complex) they do not generate hydrogen peroxide and do not require catalase for the elimination of this harmful by-product. —Preceding unsigned comment added by Nedemandeplus (talk • contribs) 16:00, 10 March 2009 (UTC)
Catalase and the Bombardier Beetles
The section on how the Bombardier beetle uses catalase is a bit confusing and doesn't seem to conclude with what it does with that reaction. It might need rewording, but I'm not entirely sure what to change it to, maybe some one else might have the skill, Abergabe (talk) 15:50, 28 June 2010 (UTC)
- The key point that was left out is that the oxidation reaction is very exothermic. I have attempted to clarify this section in this edit. Cheers. Boghog (talk) 18:30, 28 June 2010 (UTC)
Food sources of Catalase?
Does anyone know which foods are a good source of catalase? I would like to know, so I can consume these types of foods and try and restore the color of my hair which has gone a little grey. I believe that eating foods, which are a good source of catalase, is better than taking a vitamin supplement which contains catalase.220.127.116.11 (talk) 19:14, 4 August 2010 (UTC)Bennett Turk
Two links that list food sources of the enzyme catalase. 18.104.22.168 (talk) 14:57, 12 October 2010 (UTC)Bennett Turk http://curiouslyawesome.com/2008/5/13/necessary-nutrients-for-a-new-improved-you http://www.tandurust.com/antioxidants/catalase-enzymes-antioxidants.html
While all living things, animal and plant, that depend on oxygen and the carbon cycle produce Catalase to offset internal H2O2 production. There is no Catalase that survives digestion. When you eat animal or plant material, regardless of its Catalase content, digestion breaks it down to small amino acids that are then absorbed for nutrition. Catalase that could be reactive no longer exists. References: • "Biology"; Neil A. Campbell, et al.; 2008 • Colorado State University: Absorption of Amino Acids http://www.vivo.colostate.edu/hbooks/pathphys/digestion/smallgut/absorb_aacids.html • "Lehninger Principles of Biochemistry"; David L. Nelson and Michael M. Cox; 2008 • Can Catalase Be Absorbed in Foods?; By John Brennan; Sep 5, 2011 — Preceding unsigned comment added by Al simon (talk • contribs) 00:44, 14 October 2011 (UTC)
As the previous writer states, catalase is going to be broken down in the digestive system to amino acids. No catalase will reach the bloodstream. So catalase pills are fraudulent.Fletcherbrian (talk) 19:10, 9 July 2014 (UTC)
Iron becomes oxygen?
This is confusing. Catalase reacts with hydrogen peroxide by turning it into water and oxygen? Where does the extra oxygen atom come from? It sounds like you're saying that FeIV becomes the extra atom. I know I'm ignorant, can someone dumb it down for me? Thetrellan (talk) 17:05, 5 July 2012 (UTC)
- Not at all a dumb question. The answer is provided later in the article: 2 H2O2 → 2 H2O + O2 I am not sure how to fix this however since the lead is supposed to be kept dead simple and the answer to your question requires a somewhat more involved answer. Boghog (talk) 18:30, 5 July 2012 (UTC)
"Human catalase works at an optimum temperature of 45 °C" not comfirmed in source
(English is not my native language, I'm sorry for possible grammar errors)
According to the Celluar Roles section of this page "the Human catalase works at an optimum temperature of 45 °C." But the source  doesn't mention a temperature of 45C anywhere, even when accessing the full pdf. I'm not a scientist or anything, just a student, and I most likely just made a error, but can someone else check if it is verified somewhere.
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