Talk:Adenosine triphosphate

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Contents

[edit] PLEASE HELP --> What is the importance of ATP formation during Glycosis and Krebs Cycle?

Sorry, Wikipedia is not a place to ask for help with your homework.
Actually, there is a place to ask questions like this, just check out the Reference desk. --Lexor|Talk 14:07, Nov 9, 2004 (UTC)
I stand corrected -- I wasn't aware of the reference desk. However, I hope you'll agree that the original poster's question doesn't go here. Zack
Yes, it shouldn't go here, I always direct such questions to the reference desk. --Lexor|Talk 13:07, Dec 30, 2004 (UTC)
I would argue that even the reference desk is not a place for homework questions. If the questioner has got this far it does not seem unreasonable to expect them to read the articles. At the reference desk it is appropriate to answer by pointing out the relevent article but not to give the answer. I'm not saying we should not give help in finding the answer but just handing it over seems a little lame. Some questions at the reference desk are obviously not homework so i would normally be happy asnwering such questions. Obviously it is a bit subjective trying to draw the line between the two. David D. (Talk) 19:09, 30 December 2005 (UTC)
The way a librarian would do this to say, Please ask questions of this sort at the reference desk, but since you;re already here, I'll help you this once. The articles (and sections) you should read are .... Start with the..."

The key part of this is"just this once"

[edit] Formatting comment

Firefox's view of this articles is fugged'up. The top image and chart are streched till the middle of the left panel.

Fixed, thank you. TimVickers 22:09, 11 April 2007 (UTC)


[edit] GTP vs ATP

I dont understand why is GTP used in some reaction in place of ATP eg. in gluconeogenesis.

While ATP and GTP are energetically equivalent (i.e., the same amount of energy can be harnessed from ATP as from GTP), their use in biochemical reactions is enzyme-dependent. Some enzymes, such as succinyl-CoA synthetase, use GTP to drive catalysis. Others, like hexokinase, require ATP instead. Which nucleotide gets used depends heavily on the specificity of the enzyme in question, which in turn depends on the enzyme's amino acid composition and secondary/tertiary structures.
Also, for what it's worth, the production of GTP instead of ATP by certain enzymes is inconsequential since GTP can be converted to ATP via substrate-level phosphorylation. --Diberri 22:54, 2 Mar 2004 (UTC)
I believe there is also an anabolic/catabolic and protein/fat/carbohydrate/nucleic acid distinction at work in there as well. My guess is there is separation to allow the cell to target energy resourses to specific pathways. Can anybody confirm this? --Anonymous
Yes, I know that this discussion is over a year old, but it's been sitting unanswered for far too long. I'll find the answer and look it up. – ClockworkSoul 18:25, 30 December 2005 (UTC)
Okay, I got an answer: there is no functional distinction between ATP and GTP. As per Dr. Robert S. Haltiwanger, Department of Biochemistry and Cell Biology, State University of New York at Stony Brook:
There is no logical reason why ATP is used over GTP. It's like asking why do we only use L-amino acids instead of D-amino acids. You can ask God when you get to heaven.
There are several reactions that use GTP in preference over ATP, such as succinyl-CoA synthetase, but there does not appear to be any clear distinction as there is for NADH and NADPH.
This is partially untrue. While the reason for ATP's role difference over GTP is unclear (in terms of etiology; and may be arbitrary) there *is* a clear distinction between the usage-modes of ATP vs. GTP. Outside of reactions where they are used as synthetic accessories, ATP is used primarily as an energy exchange medium; the breaking of ATP's phosphodiester bonds are used to perform irreversible work, and the ADP is typically immediately released by the enzyme involved in the process so that it may be recycled. HOWEVER, the energy released by GTP is used to irreversibly change the conformation of the enzyme, sort of a molecular switch. The resultant GDP remains bound to the enzyme, altering its conformation, and thus its function. Later, accessory proteins called GEFs (GDP/GTP exchange factors) remove the GDP and allow the process to recycle. So in this case energy is used to ratchet the enzyme through three states - apo, holo-gtp, and holo-gdp. The conformations (and functions) are different in all three states, and the halflives of each state are carefully titrated by evolution to enable the molecule to correctly perform its function. Thus GTP is not merely an "energy store" but an accessory for molecular switching. UTP in eukaryotes has a general use as a transport handle; small molecules are often tagged with UDP to get them across certain lipid bilayers. "alternative" (i.e. non-rna-synthesis) roles for CTP have been less well explored.

[edit] Copyvio

I removed a section added by User:Jerryseinfeld it was a copyvio: a series of verbatim paragraphs from http://www.hussman.org/fitness/. --Lexor|Talk 13:07, Dec 30, 2004 (UTC)

I noticed that the site has a statement: "Brief quotations which include attribution and a link to this website are authorized for noncommercial use." Nevertheless, I removed it because:

  1. it was more than a brief quotation (several consecutive paragraphs)
  2. the GFDL does not restrict commercial use, and we don't encourage the addition of material that prevents commercial reuse or distribution.

So i'm wondering, since ATP is basically how cells store energy, would it be possible to just eat a bunch of ATP's directly and get some energy from them? :) SECProto 01:59, Feb 25, 2005 (UTC)

It'd be more fun to eat a bunch of LSDs :-) --69.234.183.71 01:09, 19 Mar 2005 (UTC)
I'm no biochemisty, but I expect that the ATP would undergo hydrolysis before it made it to the muscles. This article also states, "ATP cannot be stored, hence its consumption must closely follow its synthesis." so it looks like shooting back those little coffee-shop sachets of sugar is the best you can do. --Maelin 03:59, 28 December 2005 (UTC)
ATP is far too unstable to just be eaten and consumed. It's far more efficient just to consume sugars and carbohydrates and derive energy from them. – ClockworkSoul 12:50, 28 December 2005 (UTC)
ATP cant be stored as such so "eating it" would be pointless, furthermore it is constantly being utilised by the body so the effects would be very short term. Further to that the body would use its ATP in ~3s during very intense explosive exercise (ie first 10m of 100m sprint), but rapid regeneration occurs via creatinephospate (ie ATP+CP energy system). You can increasine CP stores in the muscle via creatine supplementation and in fact that is what weight lifters and body builders do, it is a proven ergogenic aid. hope that helps somewhat. StrengthCoach 20:41, 5 February 2006 (UTC)

[edit] Caffeine and ATP

Correct me if I’m wrong however doesn’t Caffeine disrupt the regular flow of ATP throughout out the body, i.e. the hit you get about 1/2 an hour after drinking a cup of coffee.

  • Take a look at the caffeine article. It doesn't directly affect the utilization of ATP, it inhibits the binding of adenosine with a cell surface receptor that normally serves to suppress neuronal activity, resulting in a net increase in central nervous system activity. It is important to note that adenosine, in this case, is entirely seperate from ATP: these two functions just happen to use the same base molecule (the receptor in question is on the outer surface of the cell membrane, whereas ATP tends to only be found on the inside of cells). – ClockworkSoul 05:00, 31 December 2005 (UTC)

[edit] Adenosine (Not ATP)

Reference to my last question, it is adenosine that causes ATP to lose its Phosphates and turn into normal adenosine (which is now thought to be a factor in determining sleep cycles)(I think) See Adenosine and Sleep for further reading

[edit] pKa

I think that the chemical structure featured in the image may be incorrect. All of the sources I can find show the terminal phosphate of ATP as being dehydrogenated and bearing a -2 charge at physiological pH. Does anybody happen to know the pK1 of ATP? – ClockworkSoul 21:21, 29 January 2006 (UTC)

form that often reacts with enzymes; bearing a -2 charge and complexed with something like Mg+2. Without a divalent cation, net 4 negative charges.

I'm not sure how the divalent cations inside cells influence this, but the pka for the second ionizing group on the terminal phosphate is about 7 and this source says: the overall charges of ATP and ADP at physiological pH are -3.5 and -2.5 --JWSchmidt 22:05, 29 January 2006 (UTC)

  • Ah, good: I'm not crazy. In that case, given the best available information, perhaps we should remove that terminal hydrogen from the chemical structure image, and assign that terminal P the proper charge of -2, for a net of -4? – ClockworkSoul 05:57, 30 January 2006 (UTC)
    • I just changed the picture in commons. see what you think. i can adjust it if needed. Or go ahead an make other modifications as needed. David D. (Talk) 06:14, 30 January 2006 (UTC)
    • Looks great to me. I'm running out now so I don't have time to upload it to en, but I'll get it when I get home later if nobody else beats me to it. – ClockworkSoul 14:11, 30 January 2006 (UTC)
The leaving of the first proton (any of the four in the "phosphate" part) gives a net (-) charge to the whole molecule wich makes it dificult for a second proton to leave, thus resulting in a higher (or lower, depending how you look at it) pK2 value. The same applies for the third leaving proton - its pK3 is even higher (lower). Without any cations only two of the phosphate -OH groups would dissociate, inside the cell the divalent cations (mostly Mg2+) would shield the charges resulting from the leaving of the first 2 protons bringing the net charge to 0 - this will allow the last two -OH groups to dissociate. - Boris 18:55, 10 February 2006 (UTC)

[edit] ER vs Wikipedia

I AM NOT AN EXPERT ON BIOCHEMISTRY, but I just watched the most recent episode of the TV show ER on TiVo and the numbers they quoted disagree with this article. On ER a "biochemistry professonr" said that there was 1/2 lb of ATP in a human body (I assume that means ADP + ATP since they are inter-converted) and he also said that each molecule was recycled 300 times per day. If I understand this article, the body has 0.1 mole x 507 g/mole = 50.7 g which is less than 1.8 ounces instead of 8 ounces. Also this article says ATP is recycled 2000 to 3000 times per day instead of 300. I doubt that the writers of ER just made up these numbers - I hope they came from some expert. So what do the experts on Wikipedia say about this discrepency? - FrankH 04:50, 7 February 2006 (UTC)

These are the numbers I have at hand for an average size human at rest. I can drag out the reference if you are interested. This does not help with your figures above
9 x 1020 molecules of ATP are metabolised each second.
65kg of ATP produced each day per person (obviously we don't gain weight this is reflected in the high turnover of the molecule.
Consume 700g glucose
Excrete 1kg carbon dioxide
Given those numbers 65,000/50.7 would suggest that the turnover (recycle) is 1300. Given my figures are for at rest the wiki article would appear to be in the right ball park. If the quantity of ATP is nearer 220g, as suggested by ER, then the turnover rate would be 300 as the show suggests. So the disputed figure here is the total ATP in the body (I would argue that is ATP, ADP and AMP). I suspect ER had the correct amount of ATP turned over each day but overestimated the amount of ATP in the body. David D. (Talk) 06:19, 7 February 2006 (UTC)
As an update this web page has an upper limit of 85g of ATP per person. David D. (Talk) 14:45, 7 February 2006 (UTC)
Thanks DavidD, I am glad that Wikipedia is closer to the truth than ER. - FrankH 05:42, 12 February 2006 (UTC)

Also a suggestion for section "1 Chemical Properties". Figures of -12 kCal/mole and -7.3 kCal/mole mean nothing to me, so when it says "This massive release of energy...." it would be very helpful if there were a comparison that would be more meaningful to me. For example, compare the energy content of common sugar or fat per gram to the energy content of ATP per gram. Any expert able to supply this kind of comparison? - FrankH 04:50, 7 February 2006 (UTC)

It is not that simple and it is a misrepresentation to say there is a massive release of energy. That needs to be changed. In fact ATP the terminal phosphoanhydride bond is an intermediate energy bond. Also you seem to be equating the energy of ATP with the whole molecule but we are only dealing with one chemical bond in ATP. The -7.3 kcal/mol (or -12 kcal/mol depending on the physiological concentrations) above is the free energy available for work after the hydrolysis of ATP to ADP. I could tell you that glucose has almost 686 kcal/mol for the oxidation of glucose to carbon dioxide and that provides enough energy to synthesis about 36 ATP molecules from ADP. Since the synthesis of ATP would require at least + 7.3 kcal/mol the energy required would be 36 x 7.3 = 263. Consequently not all the energy from glucose oxidation would be used and there is an efficiency of about ~40% (actually very good compared to most machines). I think this is partly what you were hoping for although i do not think it is what will make it more meaningful.
The key is to compare the free energy available from the hydrolysis of ATP to ADP compared to other similar reactions. The hydrolysis of glucose 6-phosphate to glucose releases -3.3 kcal/mol. on the other hand the hydrolysis of phosphoenolpyruvate to pyruvate releases -14.8 kcal/mol. As i said ATP is an intermediate energy molecule. This make sense since it is reactions such as phosphoenolpyruvate to pyruvate that can phosphorylate ADP back to ATP by substrate level phosphorylation. For such a reaction to occur it has to release more free energy than is required to make ATP (7.3 -12 kcal/mol) and of course it does. If ATP was a high energy molecule it would be much harder to synthesis it in the cell. David D. (Talk) 06:22, 7 February 2006 (UTC)
Again, thanks DavidD - FrankH 05:42, 12 February 2006 (UTC)
For what it's worth, the molecule that the professor pointed to in that episode and called "ATP" wasn't actually ATP; it was the supramolecular complex called "ATP synthase", whose role is to make ATP. I guess a small molecule just doesn't look as sexy on screen as a huge protein.
I find this all to be very ambigious as it depends on many things. Like what are we counting as ATP? Are we including ADP and AMP? 5'3' cAMP? WikipedianProlific(Talk) 12:22, 22 October 2006 (UTC)
Since this is a question of turnover, we are discussing ATP; how many ATP molecules are produced per unit of time. If one condsiders this value for any given day it is much greater than the total pool of ATP, ADP and AMP. This is still a very ambiguous discussion, however, since it is never possible to get an accurate value. There are way too many variables. David D. (Talk) 22:21, 22 October 2006 (UTC)

[edit] Stored??

Just a question- I'm not a biochem expert, but I'm taking an in-depth bio course and I was a bit confused by the statements "ATP is able to store and transport chemical energy within cells." and "ATP molecules are also used to store energy during the process of photosynthesis, as well as being the store of energy output from cellular respiration." I thought that energy in ATP could not be stored... Or does this just mean that it works as an energy carrier and not necessarily as a "store"? Matt White 02:04, 14 February 2006 (UTC)

It all depends on th time frame. It does store energy in the sense that it is not lost as heat. But you're right that in the long term it does not store energy. David D. (Talk) 12:56, 14 February 2006 (UTC)
The term "store" in this context is misleading, and I'm thinking of altering it. Fat and carbohydrates are both storage mediums; ATP, no. – ClockworkSoul 15:25, 14 February 2006 (UTC)
I made some quick changes, but they still don't feel quite right to me. Unfortunately, I don't have the time to polish it, so that task will have to fall to somebody else for now. – ClockworkSoul 15:30, 14 February 2006 (UTC)
Actually none of these molecules stores energy per se. Fats and carbohydrates produce most of their energy only when burned in oxygen, and even the breakdown of glucose to lactic acid produces energy only because it's hydrated lactate and the bonds in COOH are also more powerful and stable than anything in a sugar or alcohol. The problem with ATP is that generations of students have been told that there's something special about those phosphate bonds, that they give energy when broken. They don't. All chemical bonds take energy to break, or they wouldn't exist in the first place. Energy from ATP is obtained when the phosphate bonds are broken AND the products are hydrated. It's the hydration energy that drives the whole process. If you didn't have water and the proper concentrations, the thing would go nowhere. In that sense, water is sort of the "second fuel" which make this process go, in somewhat the same way that oxygen is the forgotten part of the energy that "exists" in a bit of food. Actually the energy isn't in the food per se, but rather can be extracted from the potential combination of food/fuel and oxygen. Same with ATP. SBHarris 23:16, 20 October 2006 (UTC)

[edit] the value of activation energy

Does anyone can tell me, From which paper or book did they cite the sentance : "The net change in energy of the decomposition of ATP into ADP and an inorganic phosphate is -12 kCal / mole in vivo, or inside of a living cell, and -7.3 kCal / mole in vitro, or in laboratory conditions. "

I would imagine every biochem text book. The -7.3 is the free energy for the rection at standard conditions (by definition everything at 1M concentration at pH 7, 25˚C and 1 atm pressure). The -12 is at phsiological condition where the energy charge has about 5 fold more ATP than ADP, compared to 1:1 at standard conditions. David D. (Talk) 07:26, 16 February 2006 (UTC)
By the way that is not the activation energy. It is the free energy of hydrolysis from ATP --> ADP + Pi. David D. (Talk) 17:27, 16 February 2006 (UTC)

[edit] ATP redirect

Currently the acronym ATP is the ATP (disambiguation) page. Given this fact, why do we have the text:

"ATP" redirects here. For other uses, see ATP (disambiguation).

At the top of the page? Shouldn't it read something along the lines of:

The acronym "ATP" redirects to ATP (disambiguation).

Or are their plans ahead to have the "ATP" redirect to this page? David D. (Talk) 16:38, 9 June 2006 (UTC)

[edit] Bafilomycin redirect

Why does Bafilomycin (BAF) redirect to the ATP page when there is nothing about Bafilomycin on the page? Dr Aaron 06:24, 21 July 2006 (UTC)

I fixed it to go the ATPase. David D. (Talk) 17:42, 21 July 2006 (UTC)

[edit] Is the density correct..??

The density is listed as 67 g/cm3 = 67000kg/m3... On the density page it is stated that "The most dense naturally occurring substance on Earth is iridium, at about 22650 kg/m3". On of these statements must be wrong.... I don't know where to check it though.... Kjaergaard 18:55, 4 September 2006 (UTC)

Fixed. A vandal added that figure a while ago; thanks for pointing it out. TenOfAllTrades(talk) 14:58, 9 September 2006 (UTC)

[edit] ATP in the human body

I don't really agree with the figure of 200-300 mole of ATP for daily need. It would mean 150kg of ATP and I heard in a biophysic course that it was about the third of that . Should somebody add a reference to back those figure, and gave some precision about this need (ie, is it the effective comsuption of all our cells are what we need to eat as energy but fail to convert in atp?) —The preceding unsigned comment was added by 82.224.181.243 (talk • contribs).

There is a Nature article that cites 9 x 1020 molecules of ATP are metabolised each second at rest. I'll have to find the reference again but it is the one i used to get the figure at the top of this talk page. If true, that equates to 130 moles per day. That is not so different to the figure above, especially if that human is active. David D. (Talk) 21:55, 27 September 2006 (UTC)

[edit] Reorganisation

I've had a go at reorganising:

1 Chemical properties 1.1 Ionisation of ATP in biological systems 2 ATP Metabolism 2.1 Synthesis 2.1.1 Anaerobic resipiration 2.1.2 Anaerobic resipiration 2.1.3 ATP production by NDKs 2.1.4 ATP production during photosynthesis 2.1.5 ATP recycling 2.2 Energy release 3 ATP in cell signaling 4 ATP use in nanotechnology 5 Reference 6 See also 7 External links

This needs a lot of work still, but I think my reorganisation best highlights some of the things that need to be done. Those in bold in particular need more research. Dr Aaron 04:14, 3 October 2006 (UTC)

  • Where does ATP as a regular of the activity of enzymes and other proteins fit in?--Peta 06:07, 3 October 2006 (UTC)

hmm.. there's a typo in aerobic respiration. i cant seem to find it in the actual wiki text though.

[edit] 3d Structure of ATP

I was going to add high quality 3d images of ATP, in the QuteMol style, but i have found that there are various ATP 'shapes' around. for example at http://xray.bmc.uu.se/hicup/ATP/ there are two different pdb files, one experimental and one ideal, both of them different from the one currently featured. What should i use? Any suggestion of other PDB files of ATP? Eventually with H atoms?

ALoopingIcon 15:43, 5 October 2006 (UTC)

IMO, pretty much anything but the idealized version. It looks like 1xdn is just an "ordinary" structure, not some high-resolution study of ATP or anything, and I imagine the angles are somewhat flexible; you can probably use whatever ATP conformation gives the best view of its shape. I rather like the current one. (I'd also go hydrogenless for the space-filling view at least.) Opabinia regalis 05:22, 10 October 2006 (UTC)
Ok, thx for the comment. I will put the first one. If someone can point me to the pdb file used for the last image i would re-make also that. ALoopingIcon 10:03, 10 October 2006 (UTC)
Before adding the image i created also the animated version. What do you think? it is too distracting? ALoopingIcon 21:57, 11 October 2006 (UTC)
I haven't gotten around to editing the actual article much, but - I like how the animation shows the 3d structure but would rather see the rotation slowed down a bit. Also, having it in the same rough orientation as the others (ie, vertically flipped 180) might be clearer. Opabinia regalis 07:50, 15 October 2006 (UTC)
I like the animation! Maybe a bit slower. In general I prefer licorice-like depictions rather than space filling because in space filling I find it hard to grasp the atomic structure. But thats just me... Splette Image:Happyjoe.jpg Talk 19:34, 15 October 2006 (UTC)

[edit] Krebs not Kreb

The man is Sir_Hans_Krebs. So it is the Krebs cycle. . And, according to the Chicago manual, the possessive is Krebs's, not Krebs' -- I've fixed themDGG 18:12, 5 October 2006 (UTC)

oops. I forgot to go back here and check. thanksDGG 04:39, 6 October 2006 (UTC)
Fixed the link. In English, it would indeed be Krebs' cycle. But also the Krebs cycle. SBHarris 20:48, 21 January 2007 (UTC)

[edit] Question

Shouldn't another hydrogen be connected to the oxygen on the lefthand side of the diagram?76.21.2.201 20:14, 25 December 2006 (UTC)James

  • No... at the pH inside cells - also called physiological pH - the hydrogens that are not shown in the diagram are generally not there. At lower pH levels there are more H+ ions present, making it more likely that those oxygens will be protonated. – ClockworkSoul 01:20, 26 December 2006 (UTC)

[edit] Passed GA

A nice written article, very well-referenced and well illustrated. I am not a molecular biologist, so I assumed that all formulas are correct. Perhaps one bit of story when ATP was discovered is good to add for a common reader interests. Nice job! — Indon (reply) — 15:15, 2 January 2007 (UTC)

[edit] DOPING?

Is ATP leagal for sportsmen??? —The preceding unsigned comment was added by 88.148.149.131 (talk) 20:32, 21 January 2007 (UTC).

Yes, but I wouldn't expect it to have any significant effect on strength or endurance, which is probably why it isn't controlled. TimVickers 20:34, 21 January 2007 (UTC)

[edit] B-Class

This article clearly qualifies as a good B-Class, hence it Good Article. However, the WP:Chem wikiproject doesn't have a GA-class, therefore I administratively rated it as B. After improvement of the remaining suggestions in the comment, it can be commended on the WP:Chem peer review page for promotion to A-Class. That's how it's done in WP:Chem. Wim van Dorst (Talk) 22:43, 14 April 2007 (UTC).

[edit] Can I have some of that crack you're smoking?

Typically, a human will use up their body weight of ATP over the course of the day.

This is not possible unless a human typically consumes their body weight in food every day, and excretes their body weight in waste every day, which they don't. People typically consume 2-3% their body weight in food per day, regardless of obesity.

No nuclear fusion occurs in the human body, so it can't produce mass from nothing. Unless I'm missing something and ATP can be used more than once, which means it's false that it's "used up" in the manner described above, and it's also false that ATP can't be stored. That would be a form of storage.

It's not possible to metabolize more energy than you consume, unless you're operating on a debt diet, in which case after the course of about a week the body will begin to catabolize its own brain and the specimen is severely malnourished and in danger of death.

--76.224.78.226 04:25, 26 July 2007 (UTC)

Read the entire paragraph again carefully, if you still don't understand, please outline here what it is you are having difficulty grasping. Tim Vickers 04:41, 26 July 2007 (UTC)
ATP is recycled - not synthesized de novo. Does that help? Dr Aaron 07:03, 26 July 2007 (UTC)

[edit] Automatic addition of "class=GA"

A bot has added class=GA to the WikiProject banners on this page, as it's listed as a good article. If you see a mistake, please revert, and leave a note on the bot's talk page. Thanks, BOT Giggabot (talk) 04:35, 10 December 2007 (UTC)

[edit] citations needed: ATP as high energy molecule

For the two needed citations about ATP as high energy molecule, citation 5 cited in the sentence before can be used: Nicholls and Ferguson, Bioenergetics 3, 2002, ISBN: 0-12-518121-3, chapter 3. Pfrederix (talk) 09:56, 15 April 2008 (UTC)

Yes, I had intended that to be a citation for all of this, but have added the additional tags. Tim Vickers (talk) 14:59, 15 April 2008 (UTC)

[edit] need to change the interwiki

the hebrew interwiki was changed to he:אדנוזין תלת-זרחתי

but the article is locked and I canwt change it Motyka (talk) 10:54, 14 May 2008 (UTC)

Done. Tim Vickers (talk) 16:04, 14 May 2008 (UTC)

[edit] ATP is not high energy and is unstable?

In the article it says: [5] ATP is commonly referred to as a "high energy molecule"; however this is incorrect, as a mixture of ATP and ADP at equilibrium in water can do no useful work at all.[5] ATP does not contain "high-energy bonds", and any other unstable molecule would serve as a way of storing energy, if the cell maintained its concentration far from equilibrium.[5]

I dont really agree with this phrase. It tries to imply that ATP is not a "high energy molecule" because ATP and ADP in equilibrium do no useful work. But in fact any kind of molecule (be it high energy or not) in equilibrium with its products also does no useful work. To make any sort of statement about the high (or not energy) of ATP one would have to compare the energy release from that molecule to others. The given argument does not prove such a thing.

Also in the article it says: "ATP is an unstable molecule and tends to be hydrolysed in water"

I am also not completely sure about the way this statement is written, although it is true that ATP is somewhat unstable (it is important to understand that everything is relative) and tends to be hydrolysed in water, it is exactly its stability (perhaps compared with other similar energetic molecules) that define its utility as an energy token. If ATP would not be stable the cell would not be able to keep the ATP - ADP system far from equilibrium, because ATP would be very quickly hydrolysed into ADP. Being more stable, it is only transformed into ADP when used by kinases.