Hemes on a string: insights on the functional mechanisms of PgcA from Geobacter sulfurreducens

Research output: Contribution to journalArticlepeer-review

1 Citation (Scopus)
1 Downloads (Pure)

Abstract

Microbial extracellular reduction of insoluble compounds requires soluble electron shuttles that diffuse in the environment, freely diffusing cytochromes, or direct contact with cellular conductive appendages that release or harvest electrons to assure a continuous balance between cellular requirements and environmental conditions. In this work, we produced and characterized the three cytochrome domains of PgcA, an extracellular triheme cytochrome that contributes to Fe(III) and Mn(IV) oxides reduction in Geobacter sulfurreducens. The three monoheme domains are structurally homologous, but their heme groups show variable axial coordination and reduction potential values. Electron transfer experiments monitored by NMR and visible spectroscopy show the variable extent to which the domains promiscuously exchange electrons while reducing different electron acceptors. The results suggest that PgcA is part of a new class of cytochromes - microbial heme-tethered redox strings - that use low-complexity protein stretches to bind metals and promote intra- and intermolecular electron transfer events through its cytochrome domains.
Original languageEnglish
Article number105167
Number of pages15
JournalJournal of Biological Chemistry
Volume299
Issue number10
DOIs
Publication statusPublished - Oct 2023

Keywords

  • electron transfer
  • Geobacter
  • Metalloprotein
  • multiheme cytochromes
  • nuclear magnetic resonance (NMR)
  • protein domain
  • Respiratory chain

Fingerprint

Dive into the research topics of 'Hemes on a string: insights on the functional mechanisms of PgcA from Geobacter sulfurreducens'. Together they form a unique fingerprint.

Cite this