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Difference between revisions of "SUIT-027"

From Bioblast
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::: '''[[SUIT protocol pattern]]:''' ce1;1Dig;1M;2D;3M;4P;5G
::: '''[[SUIT protocol pattern]]:''' ce1;1Dig;1M;2D;3M;4P;5G
SUIT-027 is focused on the analysis of the [[Malate anaplerotic pathway control state|malate anaplerotic pathway control state]] in [[mitochondrial preparations]] (isolated mitochondria, permeabilized cells, homogenate, and permeabilized fibers). [[Malate]] alone does not support respiration if oxaloacetate is not metabolized in the absence of acetyl-CoA. The careful titration of malate is required to analyze the activity of the mt-isoform of NADP<sup>+</sup>- or NAD(P)<sup>+</sup>-dependent malic enzyme (mtME). If these enzymes are present in the sample one should be able to reach with malate alone a high respiratory activity comparable to the NADH linked pathway control states with more classical combinations of substrates (e.g. PM or GM).


SUIT-027 is focused on the analysis of the [[Malate anaplerotic pathway control state|malate anaplerotic pathway control state]] in [[mitochondrial preparations|mt-preparations]] (isolated mitochondria, tissue homogenate, permeabilized cells and permeabilized fibers). [[Malate]] alone does not support respiration of mt-preparations if oxaloacetate cannot be metabolized further in the absence of a source of acetyl-CoA. However, if malate anaplerotic pathway control state is present (e.g. [[Malic enzyme|mt-malic enzyme (mtME)]]), then malate alone supports mt-respiration. SUIT-027 includes a careful titration of malate which is required to analyze the malate anaplerotic pathway control state.


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  Communicated by [[Cardoso LHD]] and [[Garcia-Souza LF]] (last update 2019-07-01)
  Communicated by [[Cardoso LHD]], [[Garcia-Souza LF]] and [[Doerrier Carolina|Doerrier C]] (last update 2020-04-30)


== Specific SUIT protocols ==
== Specific SUIT protocols ==
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== Strengths and limitations ==
== Strengths and limitations ==
:::+ Multiple titrations with [[malate]] provide information on:
:::+ Multiple titrations with [[malate]] provide information on:
:::# The presence of malate anaplerotic pathway due to mitochondrial [[malic enzyme]] in the studied sample.
:::# The presence of malate anaplerotic pathway (e.g. [[malic enzyme|mt-malic enzyme]]) in the studied sample.
:::# Malate concentration that does not stimulate malate anaplerotic pathway, and therefore could be used to study [[F-pathway]] without [[N-pathway]] contribution in samples with mt malic enzyme.  
:::# Malate concentration which does not stimulate malate anaplerotic pathway, and therefore could be used to study [[F-pathway]] in OXPHOS state avoiding FAO overestimation in the presence of anaplerotic pathways (see [[SUIT-002]]).
:::- This protocol does not analyze [[Coupling control state|coupling control]].
:::- This SUIT protocol does not analyze [[Coupling control state|coupling control]].
:::- Different [[pathway control states]] are not analyzed in this protocol.
:::- Different [[pathway control states]] are not analyzed in this SUIT protocol.
 


== Compare SUIT protocols ==
== Compare SUIT protocols ==
::::* [[SUIT-007]]: Protocol to analyze glutamate anaplerotic pathway.
::::* [[SUIT-007]]: SUIT protocol to analyze glutamate anaplerotic pathway.
::::* [[SUIT-002]] and [[SUIT-025]]: A low concentration of malate is initially used to assess F-pathway without N-pathway contribution. Further, a higher concentration of malate is added to analyze N-pathway.
::::* [[SUIT-002]]: SUIT-002 allows the evaluation of pathway control in OXPHOS state (F, F(N), FN, FNS, FNSGp pathways) and in ET state (FNSGp and SGp) whereas in SUIT-027 only malate anaplerotic pathway and N-pathway in OXPHOS state can be evaluated. A low concentration of malate is initially used to assess [[F-pathway]] without N-pathway contribution. Further, a higher concentration of malate is added to analyze FN-pathway.
::::* [[SUIT-025]]: SUIT-025 allows the evaluation of different ET-pathway states (F, F(N), FN, FNS and S) in OXPHOS state. A low concentration of malate is initially used to assess [[F-pathway]] without N-pathway contribution. Further, a higher concentration of malate is added to analyze FN-pathway.


== References ==
== References ==

Revision as of 10:03, 30 April 2020


high-resolution terminology - matching measurements at high-resolution


SUIT-027

Description

1M;2D;3M;4P;5G-.png

Abbreviation: Malate anaplerosis

Reference: A: Malate anaplerotic pathway

SUIT protocol pattern: ce1;1Dig;1M;2D;3M;4P;5G

SUIT-027 is focused on the analysis of the malate anaplerotic pathway control state in mt-preparations (isolated mitochondria, tissue homogenate, permeabilized cells and permeabilized fibers). Malate alone does not support respiration of mt-preparations if oxaloacetate cannot be metabolized further in the absence of a source of acetyl-CoA. However, if malate anaplerotic pathway control state is present (e.g. mt-malic enzyme (mtME)), then malate alone supports mt-respiration. SUIT-027 includes a careful titration of malate which is required to analyze the malate anaplerotic pathway control state.

Communicated by Cardoso LHD, Garcia-Souza LF and Doerrier C (last update 2020-04-30)

Specific SUIT protocols

Ce1;1Dig;1M;2D;3M;4P;5G;6Ama.png D065 O2 traces.png

MitoPedia: SUIT

Steps and respiratory states

1M;2D;3M;4P;5G;6Ama.png


Step State Pathway Q-junction Comment - Events (E) and Marks (M)
1M.05 (ML) ce1;1Dig;1M
  • Low concentration of malate, typically low concentration, does not saturate the N-pathway, and will allow us to find the minimum concentration to stimulate the anaplerosis.
2D ( MP) ce1;1Dig;1M;2D


3M MP N CI ce1;1Dig;1M;2D;3M
4P PMP N CI ce1;1Dig;1M;2D;3M;4P
5G PGMP N CI ce1;1Dig;1M;2D;3M;4P;5G
6Ama ROX ce1;1Dig;1M;2D;3M;4P;5G;6Ama
  • Rox is the residual oxygen consumption in the ROX state, due to oxidative side reactions, estimated after addition of antimycin A (inhibitor of CIII). Rox is subtracted from oxygen flux as a baseline for all respiratory states, to obtain mitochondrial respiration (mt).


Questions.jpg


Click to expand or collaps

Strengths and limitations

+ Multiple titrations with malate provide information on:
  1. The presence of malate anaplerotic pathway (e.g. mt-malic enzyme) in the studied sample.
  2. Malate concentration which does not stimulate malate anaplerotic pathway, and therefore could be used to study F-pathway in OXPHOS state avoiding FAO overestimation in the presence of anaplerotic pathways (see SUIT-002).
- This SUIT protocol does not analyze coupling control.
- Different pathway control states are not analyzed in this SUIT protocol.

Compare SUIT protocols

  • SUIT-007: SUIT protocol to analyze glutamate anaplerotic pathway.
  • SUIT-002: SUIT-002 allows the evaluation of pathway control in OXPHOS state (F, F(N), FN, FNS, FNSGp pathways) and in ET state (FNSGp and SGp) whereas in SUIT-027 only malate anaplerotic pathway and N-pathway in OXPHOS state can be evaluated. A low concentration of malate is initially used to assess F-pathway without N-pathway contribution. Further, a higher concentration of malate is added to analyze FN-pathway.
  • SUIT-025: SUIT-025 allows the evaluation of different ET-pathway states (F, F(N), FN, FNS and S) in OXPHOS state. A low concentration of malate is initially used to assess F-pathway without N-pathway contribution. Further, a higher concentration of malate is added to analyze FN-pathway.

References

MitoPedia concepts: MiP concept, SUIT protocol, Recommended 


MitoPedia methods: Respirometry