From Bioblast
Description
Cyanide (usually added as KCN) is a competitive inhibitor of cytochcrome c oxidase (CIV). Inhibition is reversed by pyruvate and high oxygen levels.
Abbreviation: KCN
Reference: MiPNet09.12
MitoPedia topics: Inhibitor
Application in HRR
Last update 2021-01-22
Inhibitor titrations, CIV-assay, alternative oxidase and ROX
- Cyanide and determination of residual oxygen consumption (ROX).
- Complex IV assay
- alternative oxidase
- Caution: Due to a confusion, a change in the procedure for preparing the KCN was done in April 2019 that recommended to prepare 20 mM KCN stock and titrate 100 Β΅l. This now have been corrected to our previous recommendation of 1 M KCN stock solutions
- O2k manual titrations MiPNet09.12 O2k-Titrations
- Titration volume: 2 Β΅l of 1 M stock, using a 10 Β΅l syringe (2 ml O2k-chamber).
- Final concentration: 1 mM.
- O2k manual titrations MiPNet09.12 O2k-Titrations
Preparation of 1 M KCN stock
- Kcn(KCN): Fluka 60178, 100 g, store at R.T.; FW = 65.12.
- Caution: KCN is photosensitive and hygroscopic; KCN is volatile and very toxic!
- Preparation of 1 M KCN stock solution for 2-mL O2k-chamber
- Weigh 13 mg of KCN.
- Dissolve in 0.2 ml H2O.
- The pH of the solution may be very alkaline - adjust to physiological pH with HCl.
- Β» O2k manual titrations MiPNet09.12 O2k-Titrations
- Titration volume (2-mL O2k-chamber): 100 Β΅L using a 100 Β΅L Hamilton syringe.
- Final concentration: 1 mM.
- Preparation of 250 mM KCN stock solution (in 45 mM Trizma base) for 0.5-mL O2k-chamber:
- Weigh 16,28 mg of KCN and dissolve in 1 mL of 45 mM Trizma base.
- Divide into 200 Β΅L aliquots (use dark glass vials).
- Store frozen at -20 Β°C.
- Preparation of 250 mM KCN stock solution (in 45 mM Trizma base) for 0.5-mL O2k-chamber:
- Β» O2k manual titrations MiPNet09.12 O2k-Titrations
- Titration volume (0.5-mL O2k-chamber): 2 Β΅L using a 10 Β΅L Hamilton syringe.
- Final concentration: 1 mM.
- Β» O2k manual titrations MiPNet09.12 O2k-Titrations
MitoPedia topics:
Inhibitor