Talk:Chemiosmotic potential

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    • There is no such thing as a "chemiosmotic potential." The word must be a conflation of chemiosmotic hypothesis and electrochemical potential.
      • Strange someone would say that, as it is in current use at Yale: http://www.mbb.yale.edu/dus/syllabi/mbb300.html. I was the one who authored the bit, and my recollection is the term is in widespread use among professors of biochemistry who specialize in electron transport proteins. David Myers
        • I want to pursue this claim of non-existence further. If you go onto Google and do a search on the phrase "chemiosmotic potential", you get 63 hits, the vast majority of which come from University lecture notes. So, ironically, the term *is* in use, it is in moderately widespread use, and serves a purpose in the community because it highlights the concentration term of such a potential, which students tend to forget.
          • One more comment. If someone dislikes the term "chemiosmotic potential" and prefers "electrochemical potential", I have no problem with the merging of my original article with the "electrochemical potential" article and turning my original into a redirect. Besides, this saves me the trouble of tracking down the half hearted job someone has done of deleting all my chemiosmotic potential links and replacing them with their own electrochemical potential links. But this, in my opinion, is exactly the same kind of pig-headed language war that get struck up, to quote an example, over the use of "polyatomic ion" versus "complex ion" versus "radical", because textbook author A has a certain preference in language versus textbook author B. And it begs the question of whether the Wikipedia is a Webster's like dictionary of language, attempting to define what language is, or whether it is truly a cornucopia of knowledge, and has the capacity to recognize that terms in practical use may not fit any neat theories. David Myers
            • Yet another comment..what the original suggestion clearly misses is that a chemiosmotic potential is a kind of electrochemical potential, in much the same way the potential of a battery is a kind of electrochemical potential. That there can be a chemiosmotic potential can clearly be seen if you bother to look up the definition of the adjective "chemiosmotic" in Websters: http://www.m-w.com. And if there can be an article about batteries, which are mere electrochemical cells, why not an article on the specific electrochemical potential referred to as a chemiosmotic potential? Removing chemiosmotic potentals from this 'pedia makes as much sense as removing articles on females, since they're just a kind of animal.

Lecture note authors are typically T.A.s who sometimes only barely have a handle on the topic. It goes without saying that "chemiosmotic" is an adjective. The fact that that Webster's site's definition doesn't throw in "typically used only to modify 'hypothesis' or 'theory'" suggests it indeed might get some use as a modifier of "potential", as you argue, but it's not conclusive and doesn't speak to whether such use is conventional or idiosyncratic. Can you cite your usage in a text book or the Web site of a professor? As I mentioned on the Talk page for "electrochemical potential," I searched for this usage in Xrefer and a couple other scientific dictionaries and couldn't find it. Also I took a couple college courses for physical scientists which each spent some weeks on ATP synthesis and I don't recognize your usage as one I ever heard (not that that's proof it doesn't happen at other colleges). As far as where things belong, "electrochemical potential" is the more all-purpose term, and it deserves an article. My hunch is that if many people think of "chemiosmotic potentials" most if not all of them would most if not all of the time only be doing so in the context of ATP synthesis. So I think it could be talked about either there or as a special case of electrochemical potential, which is how it stands now. Of course, since I'm not convinced that the term reflects accepted usage, I'd rather we weren't giving it that name. But you'd make me feel otherwise, if you were to show me a convincing reference.168...

  • I looked again on the Web. I found a use in a course description that was authored by a PhD bacteriologist and instructor [1] and wrote the fellow
                 >Hi, Dr. Todar,
                  >
                  >I noticed you have the term "chemiosmotic potential"
                  >on  your Bact303 Web site. Would you mind telling me,
                  >does this really represent a conventional term? I'm
                  >having a light-hearted quarrel with somebody about
                  >whether it does, or whether it is a rare and not
                  >really accepted conflation of "chemiosmotic
                  >hypothesis" with "electrochemical potential." It's
                  >hard to find trustworthy-seeming instances of it on
                  >the Web, although you seem like someone who might
                  >know. In the two undergraduate courses I took long ago
                  >in which we spent a few weeks on ATP synthesis, and
                  >which were tailored to upper division physical science
                  >majors, we used "electrochemical potential." I don't
                  >think I ever heard "chemiosmotic potential," not that
                  >that proves anything. Would you be willing to weigh in
                  >with an opinion? Me and my antagonist would appreciate
                  >it!
                  >
                    [signature deleted]                   
                  >__________________________________________________
                   

He replied:

I will settle for chemiosmotic hypothesis. I really don't want to get into it.

                  Kenneth Todar
                  University of Wisconsin-Madison
                  Department of Bacteriology
                   

I believe that really the person to ask is somebody who does research in bioenergetics...or somebody who owns a dozen textbooks (at this point I'd bet not one has this usage). Yet I think it's bad for your case when the first supposed source I ask and the most authoritative seeming source I've seen backs down like that. Anyway, this is just to show I've put some effort into discovering this usage among experts. 168... 02:43 Feb 9, 2003 (UTC)

    • O.K. I looked still harder and I finally found a Science paper, reporting the crystallographic structure of a transporter, which uses "chemiosmotic potential." So I'll back down. It seems some people who ought to know do use it. I still think it's unconventional though. 168... 03:51 Feb 9, 2003 (UTC)
      • and this guy[2], who really ought to know, uses it here [shiva.msu.montana.edu/courses/mb480_580_2002_fall/ docs/firstlivingsystems.pdf]. I concede 168... 04:05 Feb 9, 2003 (UTC)

I did research for several years on proteins in the electron transport chain. My PhD covered topics on cytochrome c peroxidase and cytochrome c oxidase. Why do you think I'm objecting so loudly and strenuously to this ridiculous language issue? Do you think I have no training in the area? Did you even bother to look at my user page and see if I had an iota of credentials? I used the term initially because I recall it from my class notes from Rice (We were not taught by TAs at Rice, incidentally. My first Biochem course there was taught by two full professors on the staff, Professor Kathleen Matthews and Professor John Olson; their lecture notes, I'll point out, were penned by themselves and I'm not terribly impressed by arguments coming from non-biochemists that "TAs usually pen lecture notes" because in my experience, in small selective private schools, TAs usually do not handle the course outlines). If you need a name brand scientist to tell you whether the term exists or not, why don't you look up one of the students of Peter Mitchell and find out whether they use the term or not? Or perhaps Bo Malmstrom, who clearly does research in the field and was, or still is, the chairman of the Nobel Prize Committee on Chemistry? My major professor, Graham Palmer, wouldn't be a bad man to talk to. He worked in electron transport proteins from Complex II to cytochrome c oxidase, and it is his cytochrome c oxidase page I show a link to in the cytochrome c oxidase article. He's an emeritus professor now, and tends to hang out in France, but he is a reasonable man and easy enough to speak to. You can get to him through the Rice University Biochemistry web page. If you would prefer a full professor who is still active, ask John Olson at Rice University, since it is my memory of his class notes that led to the article here. He's a hemoglobin biochemist, but something of a polyglot genius at large.

I really think though, that you're just shooting yourselves in the foot. The term is used, I'd not be objecting if I'd never seen it before.

Part of the problem of course, is one of age. The scientists familar with Peter Mitchell and the chemiosmotic hypothesis are old men now and dying off. In a century the term chemiosmotic potential and the chemiosmotic hypothesis will only be known to quaint old men who specialize in scientific history. So what is next? An argument over the term "extinction coefficient" versus "absorption coefficient"? The former is in common use but the latter is preferred. Incidentally, I do not consider this argument light hearted in any sense of the term. At the core of it, I think it is venal and mean spirited, and for the most part, I am insulted by the existence of this squabble.David Myers 24.98.55.136 13:35 Feb 9, 2003 (UTC)

  • Well, my heart was light, but I can see that wasn't obvious in my initial brazen challenge. In Wiki context, it seems reasonable to me to give you the burden of proof and to ask for a substantiation of a claim like I did without having to marshall my reasons for suspicion. But I'm sorry I didn't make an effort to be polite. I didn't mean to be mean.

168... 19:16 Feb 9, 2003 (UTC)