Talk:The protonmotive force and respiratory control

Work flow

• 2017-08-14 Added to Version 14

Coupled versus bound processes: Since the chemiosmotic theory explains the mechanism of coupling in OXPHOS, it may be interesting to ask if the electrical and chemical parts of proton translocation are coupled processes. This is not the case according to the definition of coupling given above (in the manuscript). It is not possible to physically uncouple the electrical and chemical processes, which are only theoretically partitioned as electrical and chemical components (Eq. 1) and can be measured separately. If partial processes (fluxes, forces) are non-separable, i.e. cannot be uncoupled, then these are not coupled but are defined as bound processes. The electrical and chemical part of Eq. 1 are tightly bound partial forces of the protonmotive force. (E. Gnaiger, 2017-08-14)

• 2017-08-14 Masashi Tanaka: Corrections and comments (see below).
• 2017-08-13 Brian Irving: The review is coming together nicely. Much more advanced than a couple weeks ago. Great job. I added a few comments.
• 2017-08-12 Version 12 uploaded.
• 2017-08-12 Feedback and suggestions on Version 10 by A Molina.
• 2017-08-11 Feedback and suggestions on Version 9 by J Iglesias-Gonzalez.
• 2017-08-11 HK Lee: ‘Control’ should be defined. The chapter on protonmotive force is difficult to read.
• 2017-08-10 Version 10: Integration of suggestions and corrections by T Komlodi and A Meszaros.
• 2017-08-08 to 09: Updated versions by E Gnaiger.
• 2017-08-02 Updated ms summarizing WG1 input by J Iglesias-Gonzalez.
• 2017-08-29 Version 3 on website: http://www.mitoeagle.org/index.php/Mitochondrial_respiratory_control:_MITOEAGLE_recommendations_1
• 2017-07-28 to 29: Obergurgl MITOEAGLE Workshop: WG1 – group discussion and edits based on printed Version 2.
• 2017-04-21 PX Petit: I find the text clearly exposed even if the publicity for Mitoeagle is too much pronounced (but that is a choice).
• 2017-04-18 Version 1 circulated to MITOEAGLE by E Gnaiger.
• 2017 Mar 21-23: Barcelona MITOEAGLE Workshop: WG1 – presentations and group discussions.

2017-08-14 Masashi Tanaka

Response by E Gnaiger

1. On Fig. 1A: Perhaps we should simplify it for the present purpose, since the chapter on ‘pathway control’ has been shifted away form the present Part 1 to another manuscript (Part 2), where these issues should be discussed and controversies resolved in full detail.
2. Intact cell respiration was also shifted to another future manuscript.
3. I added ‘intermembrane space’ to Fig. 1B.
4. V[dot]_O2max: I fully agree, I just do not know how to add the dot in Microsoft Word. In the old style, it was simple to just put such a dot on paper.
5. Definition of V: It is unfortunate that V[dot]_O2max has been introduced, but we cannot expect to change the sport science symbols (they should change from volume to amount of substance for metabolic oxygen consumption). And we cannot change V. Therefore V[dot] needs to be distinguished from the other definitions of V. I added: “.. whereas maximum mass-specific oxygen flux, V[dot]_O2max or V[dot]_O2peak, is constant across a large range of individual body mass (Weibel and Hoppeler 2005). V[dot]_O2peak of human endurance athletes is 60 up to 80 ml O2·min^-1·kg^-1 body mass, converted to J_m,O2peak of 45 to 60 nmol·s^-1·g^-1 (Gnaiger 2014).”

2017-08-12 Anthony Molina

I managed to set aside some time to work on the manuscript. My suggested revisions and comments are embedded in the document using the “track changes” mode and margin comments.

• On »P (»P/O ratio) and «P: Can a stronger statement be made here? I like the suggested symbols.
• On ADP concentration: It may be useful to discuss the potential confusion between high ADP and saturating ADP. The arbitrariness of some commonly used protocols is a problem in the field, particularly when using plate-based systems for measuring respiration.

2017-08-11 Hong Kyu Lee

Thank you for your generous invitation to become an author of this historical paper. This is a great honor to me. I have some comments to make;

• I wish you would elaborate more on the respiratory 'control', I always wondered how and why this term is adopted, instead of other terms, such as mitochondrial functional characteristics or functional anatomy.
• I was really happy to find a section "Size-specific quantities", where you wrote "The well-established scaling law in respiratory physiology reveals a strong interaction of oxygen consumption and body mass by the fact that mass-specific basal metabolic rate (oxygen flux) does not increase proportionally and linearly with body mass, whereas maximum mass-specific oxygen flux, VO2max, is constant across a large range of body mass (Weibel and Hoppeler 2005)." However, I understand the mass-specific (basal) metabolic rate (oxygen flux) decrease proportionally if not linearly with body mass.
• I found the discussion on the protonmotive force very challenging. I wonder if you could make it simpler for more wide audiences.

2017-08-01 Javier Iglesias-Gonzalez

I’ve just finished with the last version (9) of the paper. I really like how it looks like now and I have let some of our PhD students to read (as a test for a beginner) and she enjoyed a lot the paper. I added very few suggestions which I attached in the word document.

2017-04-21 Patrice Petit

I find the text clearly exposed even if the publicity for Mitoeagle is to much pronounced (but that is a choice).

Concerning:

• State 1: depending on the fact that mitochondrial extract of isolated mitochondria is crude or purified (for exemple on Percoll gradients or sucrose gradients), the isolated mitochondria have still somes endogenous substrats or not that makes a pulse at the start during their early dissipation. Could this be taken into consideration or being indiscted for the users.

• State 4: I do not find this very well writen since after the addition of ADP (state 3) the mitochondrial membrane potential drop and reacquire its high value (at the state 4) when all the ADP has been transformed in ATP has been used? am I wrong. So this shoul be writen clearly.

Why escaping to state about CR (respiratory control) and ADP/O measurements and definitions?

Again, I perfectly understand the reference to the bioblast link by since we do not live outside teh real world the reference are usually referred to pubmed also... so we should refer to both...

For te publication, the suggestion is nice but by tradition our journals are more....

• BBA general subjects or bioenergetic: 6554 occurrences
• FEBS J: 2911 FEBS letters 2563 (so 1+2 = 5474 Occurrences)
• Journal of Biological Chemistry: 7730 occurrences

My personnal preference will go To BBA general subjects... But should be decided in commun

Sincerely yours

Patrice - Petit PX