thylakoid

GO:0009579 · Membrane organelle · Other · Proposed

A membranous cellular structure that bears the photosynthetic pigments in photosynthetic bacteria and within chloroplasts. [GO:0009579]

Has part: thylakoid membrane (GO:0042651)

Xrefs: uniprot.location:SL-0450 — Thylakoid

Components

Component	Type	Part of / acts on	Grounding	Genes	Stoichiometry	Essential	Role
thylakoid membrane	Lipid	part of	`GO:0042651`			ESSENTIAL	Pigmented photosynthetic membrane that forms the thylakoid surface and houses photosynthetic electron-transport complexes. `GO:0042651` GO:0042651 defines the thylakoid membrane as the pigmented membrane of cyanobacterial and plastid thylakoids. `DOI:10.1146/annurev-cellbio-120823-022747` Perez-Boerema et al. 2024 review thylakoids as specialized photosynthetic membrane systems across cyanobacteria, algae, and plants.

NCBITaxon:1117 Cyanobacteriota — COMMON: Most cyanobacteria have internal thylakoid membranes, while Gloeobacter-like lineages carry out oxygenic photosynthesis at the plasma membrane and lack thylakoids. [DOI:10.1146/annurev-cellbio-120823-022747]
NCBITaxon:33090 Viridiplantae — COMMON: Photosynthetic green algae and land plants have plastid thylakoids inside chloroplasts. [DOI:10.1146/annurev-cellbio-120823-022747]

NCBITaxon:1148 Synechocystis sp. PCC 6803 — Cyanobacterial model whose native thylakoid membrane network has been imaged to map photosynthetic-complex organization. [DOI:10.1016/j.molp.2017.09.019]

photosynthesis, light reaction GO:0019684 — Thylakoids provide the photosynthetic membrane system for light reactions in cyanobacteria, chloroplasts, cyanelles, and photosynthetic chromatophores.
- uniprot.location:SL-0450 — Thylakoid UniProt SL-0450 describes thylakoids as membranous structures containing photosynthetic pigments, reaction centers, and the electron-transport chain.
- DOI:10.1146/annurev-cellbio-120823-022747 Perez-Boerema et al. 2024 review thylakoid membrane architecture as the conserved site of oxygenic photosynthetic light reactions.

Thylakoids are photosynthetic membrane structures whose pigmented thylakoid membrane surface houses light-reaction electron-transport complexes.

Subject	Predicate	Object	Evidence
thylakoid	has part	thylakoid membrane	`GO:0009579` GO:0009579 identifies a thylakoid as a membranous photosynthetic structure. `GO:0042651` GO:0042651 identifies the membrane part of thylakoids.
thylakoid membrane	supports	photosynthesis, light reaction	`uniprot.location:SL-0450` — Thylakoid UniProt SL-0450 describes thylakoids as containing photosynthetic pigments, reaction centers, and the electron-transport chain. `DOI:10.1146/annurev-cellbio-120823-022747` Perez-Boerema et al. 2024 review thylakoid membranes as light-reaction membranes.

INTERPRETATION (RESOLVED): Keep the whole thylakoid parent distinct from the generic thylakoid membrane. GO:0009579 denotes the whole membranous thylakoid structure across photosynthetic bacteria and plastids, whereas GO:0042651 denotes the pigmented membrane constituent. The whole generic thylakoid also has multiple exact child lumen classes instead of one exact generic lumen term.
INTERPRETATION (RESOLVED): Represent thylakoid as a membranous cellular structure without asserting that it is an organelle. GO:0009579 describes thylakoids as membranous cellular structures and scopes thylakoids away from the organelle class.

GO:0009579 Gene Ontology cellular-component term for thylakoid.
GO:0042651 Gene Ontology cellular-component term for the thylakoid membrane.
GO:0019684 Gene Ontology biological-process term for photosynthesis, light reaction.
uniprot.location:SL-0450 — Thylakoid UniProt Subcellular Location entry SL-0450 maps Thylakoid to GO:0009579.
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.

2026-09-13T22:19:25Z codex · CREATED_RECORD — Scaffolded by scripts/new_record.py
2026-09-13T22:20:00Z codex · EXPANDED_RECORD — Added the UniProt SL-0450 xref, the GO:0042651 thylakoid membrane part and component, Cyanobacteriota and Viridiplantae scope, a photosynthesis light-reaction function, a nonmechanistic thylakoid-membrane topology graph, and resolved whole-thylakoid boundary decisions.