Szczegóły publikacji
Opis bibliograficzny
Defining the direct electron transfer connection between alternative complex III and cytochrome oxidase in Flavobacterium johnsoniae / Katarzyna Lorencik, Robert Ekiert, Rafał Pietras, Joanna NER-KLUZA, Małgorzata Hopciaś, Artur Osyczka // Biochimica et Biophysica Acta. Bioenergetics ; ISSN 0005-2728. — 2025 — vol. 1866 iss. 2 art. no. 149548, s. 1–10. — Bibliogr. s. 10, Abstr. — Publikacja dostępna online od: 2025-02-14
Autorzy (6)
- Lorencik Katarzyna
- Ekiert Robert
- Pietras Rafał
- AGHNer-Kluza Joanna
- AGHHopciaś Małgorzata
- Osyczka Artur
Słowa kluczowe
Dane bibliometryczne
| ID BaDAP | 161598 |
|---|---|
| Data dodania do BaDAP | 2025-08-25 |
| Tekst źródłowy | URL |
| DOI | 10.1016/j.bbabio.2025.149548 |
| Rok publikacji | 2025 |
| Typ publikacji | artykuł w czasopiśmie |
| Otwarty dostęp |  |
| Creative Commons | |
| Czasopismo/seria | Biochimica et Biophysica Acta, Bioenergetics |
Abstract
Alternative complex III (ACIII) is an enzyme of electron transport chains in some bacterial species. ACIII, like cytochrome bc enzymes, oxidizes quinol and transfers electrons from quinol to electron acceptors located outside the membrane. Various proteins can functionally link ACIII with other enzymes. The structure of ACIII from Flavobacterium johnsoniae suggests that in this bacterium the membrane-anchored mobile mono-heme cytochrome c domain (mdA) of the ActA subunit of ACIII provides means for its connection with cytochrome aa3 oxidase. Here, using a recently-developed genetic system for ACIII, we revealed that ACIII mutant deprived of mdA does not exhibit electron transfer activity towards cytochrome aa3 oxidase in the cells and in the isolated membranes. These results indicate that mdA is the only carrier of electrons between the pentaheme core of ActA and cytochrome aa3 oxidase. In addition, we heterologously expressed and purified mdA and ActE (another mono-heme subunit of ACIII) from Escherichia coli to identify the redox midpoint potentials of the hemes in these two domains. The obtained values analyzed in the context of the whole titration profiles of native ACIII and ACIII deprived of mdA provide first insights into the arrangement of heme redox potentials in the seven-heme chain formed by the ActA/ActE assembly.