plasma membrane-derived photosystem I

GO:0030094 · Energy complex · Multiprotein complex · Proposed

A photosystem I protein complex located in the plasma membrane-derived bacterial thylakoid membrane. [GO:0030094]

Synonyms: cyanobacterial PSI

Part of: plasma membrane-derived thylakoid membrane (GO:0031676)

UniProt location names: UniProt Consortium, CC BY 4.0. Reference label and route sources.

Taxonomic distribution

• NCBITaxon:1117 Cyanobacteriota — COMMON: Cyanobacteria with internal thylakoids carry PSI complexes in plasma membrane-derived thylakoid membranes as part of oxygenic photosynthetic electron transport. [DOI:10.1146/annurev-cellbio-120823-022747]

Canonical examples

• NCBITaxon:1148 Synechocystis sp. PCC 6803 — Cyanobacterial model used to map photosystem I distribution and mobility in native thylakoid membranes. [DOI:10.1016/j.molp.2017.09.019]

Functions

• photosynthetic electron transport chain GO:0009767 — Plasma membrane-derived PSI receives electrons downstream of cytochrome b6f in the bacterial thylakoid electron-transport chain.
  • GO:0030094 GO:0030094 defines plasma membrane-derived photosystem I as a photosystem I complex in the bacterial thylakoid.
  • DOI:10.1146/annurev-cellbio-120823-022747 Perez-Boerema et al. 2024 review PSI as the downstream cyanobacterial thylakoid photosystem in linear electron transport.

Mechanism graphs

Cyanobacterial PSI receives downstream thylakoid electrons (FUNCTION)

In Synechocystis, plasma membrane-derived PSI complexes reside in the thylakoid membrane and act downstream of cytochrome b6f in photosynthetic electron transport.

Discussions

• CURATION_TODO (OPEN): Resolve exact source-neutral component groundings for bona fide bacterial PSI core and antenna subfamilies before adding subunit-level component rows. GO exactly grounds the bacterial thylakoid PSI complex, but this record does not yet distinguish conserved PSI constituents from soluble electron carriers or phycobilisome attachment factors.

Evidence

• GO:0030094 Gene Ontology cellular-component term for plasma membrane-derived photosystem I.
• GO:0009522 Gene Ontology cellular-component term for generic photosystem I.
• GO:0031676 Gene Ontology cellular-component term for the plasma membrane-derived thylakoid membrane that houses this cyanobacterial PSI complex.
• GO:0030075 Gene Ontology cellular-component term for bacterial thylakoid.
• GO:0009767 Gene Ontology biological-process term for the photosynthetic electron transport chain.
• DOI:10.1146/annurev-cellbio-120823-022747 Perez-Boerema et al. 2024, Evolution of Thylakoid Structural Diversity, Annual Review of Cell and Developmental Biology.
• DOI:10.1016/j.molp.2017.09.019 Casella et al. 2017, Dissecting the Native Architecture and Dynamics of Cyanobacterial Photosynthetic Machinery, Molecular Plant.

Curation history

• 2026-09-13T05:23:06Z codex · CREATED_RECORD — Scaffolded by scripts/new_record.py
• 2026-09-13T05:23:34Z codex · EXPANDED_RECORD — Added PSI synonymy, generic PSI parentage, bacterial thylakoid membrane parthood, cyanobacterial scope, a Synechocystis example, photosynthetic electron-transport function, GO and literature evidence, a nonmechanistic PSI electron-input graph, and a PSI subunit-boundary TODO.
• 2026-09-13T05:29:46Z codex · REVISED_RECORD — #754: replaced GO-only evidence on the PSI electron-transport graph edge with literature evidence for the process claim.

Source: data/structures/energy_complex/plasma_membrane_derived_photosystem_i.yaml