Talk:Chemiosmosis

Wiki Education Foundation-supported course assignment

This article is or was the subject of a Wiki Education Foundation-supported course assignment. Further details are available on the course page. Student editor(s): Mzh0015. Peer reviewers: Mzh0015.

Above undated message substituted from Template:Dashboard.wikiedu.org assignment by PrimeBOT (talk) 17:18, 16 January 2022 (UTC)

Merge

I'm going to merge many of the chemiosmotic stuff under this name. I think that it makes more sense to have one entry under chemiosmosis rather than seperate entries for Chemiosmotic hypothesis and Chemiosmotic phosphorylation. Rozzychan 23:12, 22 July 2006 (UTC)

Let the games begin

OK, I made the new article. I need references, images, and more depth on chemiosmosis in plants and bacteria. I also need someone to check the existing references. I copied them straight using two articles and do not know if they still are numbered correctly.

I hope to remove the entries for Chemiosmotic phosphorylation and Chemiosmotic hypothesis which I copied in entirety

Added image Etc3.png Rozzychan 02:29, 23 July 2006 (UTC)

Added image chemiosmosis1.png Rozzychan 03:29, 23 July 2006 (UTC)

Suggestion for the key points to make while introducing chemiosmosis (chemiosmotic coupling)

1. describe the terminal phosphate bond of ATP as the key "energy currency" of cells
2. state that chemiosmosis is widely used (mitochondria, chloroplasts, bacteria) in living cells as a way to channel chemical energy into ATP.
3. chemiosmosis requires a topologically close cellular or subcellular compartment surrounded by a lipid bilayer membrane - this was a surprise to biochemists and its discovery resulted in a Nobel prize.
4. lipid bilayer membranes are poorly permeable to protons
5. chemical energy can be used to pump protons across membranes
6. chemical energy can be stored in the form of a proton gradient across a cell membrane
7. energy from a tranmembrane proton gradient can be captured to produce ATP
   --JWSchmidt 03:07, 23 July 2006 (UTC)

chemiosmosis coupling

Someone needs to add some info on chemiosmosis coupling —The preceding unsigned comment was added by LtGeneral Snow (talk • contribs) 22:01, 6 December 2006 (UTC).

Proposed merger

I think the material on the Proton-motive force page could make a good section in this article and the Chemiosmotic hypothesis article could be added as a "History" section as it deals mostly with Peter Mitchell. TimVickers 18:18, 16 March 2007 (UTC)

These articles are now redirects to this page. TimVickers 18:04, 17 March 2007 (UTC)

Assessment comment

The comment(s) below were originally left at Talk:Chemiosmosis/Comments, and are posted here for posterity. Following several discussions in past years, these subpages are now deprecated. The comments may be irrelevant or outdated; if so, please feel free to remove this section.

Rated "top" as high school/SAT biology content and basic principle of energy storage/generation in cells. - tameeria 00:24, 19 February 2007 (UTC)

Substituted at 18:11, 17 July 2016 (UTC)

ATP synthetase is driven by a thermodynamic free energy difference, not kinetic energy

I changed "kinetic energy" to "free energy difference" as the driving force for ATP synthetase, because metabolic reactions take place in an extreme low-Reynolds-number environment where moving parts (e.g. protein subunits) are so heavily damped by molecular collisions that they have no opportunity to acquire or maintain a momentum significantly above that of random Brownian motion.CharlesHBennett (talk) 01:23, 6 October 2016 (UTC)

proton-motive force

I made a few changes, some minor, some major. There was an error in the delta G equation: mFdeltapsi should NOT have a negative sign in front of it. I also got rid of A and B phases and just used N and P.

I added a couple of paragraphs specifying that PMF is defined by default for proton import (which is spontaneous), and PMF for nonspont. proton export is simply the negative of PMF(import). Another paragraph specifies the relationship between inside/outside and N/P phases for bacteria, mitochondria, and chloroplasts.

In the calculation of proton/ATP ratio, some of the values were not quite right so I corrected them and included a reference for the new values. I also replaced the last two paragraphs with one that explains a little more clearly why to extra proton import is needed for ATP export and ADP + Pi import, and calculates the effect of this extra proton import on efficiency.

FInally, I clarified the last sentence of the "In Plants" section, which discusses water splitting, and the overall stoichiometry of oxygen generation, photon absorption, and NADP reduction. — Preceding unsigned comment added by 158.104.1.109 (talk) 23:49, 29 June 2017 (UTC)

Definition of the chemiosmosis

In my opinion definition of the chemiosmosis ("chemi - osmosis") in this article is very incorrect. It should rather about connection between osmosis ("osmotic" energy) and chemical reactions (chemical energy). In both directions. Osmosis or rather ion transport powered by chemical reactions and chemical reactions powered by osmosis. Or rather the title should be changed to chemiosmotic coupling (chemical energy <--> "osmotic" energy <--> chemical energy). Darekk2 (talk) 21:27, 26 July 2019 (UTC)

Evidence that confirmed the chemi-osmotic hypothesis

This needs adding, and I intend to make a start soon to briefly mention the acid-bath experiment and that the ATP synthase and cytochrome complexes have been characterized and their predicted role confirmed. Socialambulator (talk) 11:02, 11 February 2023 (UTC)