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CompoundsSubstances with curated findings
OutcomesMeasured endpoints
ProteinsTransporters and enzymes
InteractionsPairs that share biology
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ReactionsRhea and Human-GEM, by subsystem
ReachWhat a compound can become

Reference layer

PathwaysReactions grouped under one name
ProcessesWhat proteins are annotated as doing
AnatomyTissues, by what is expressed there
Cell typesCells, by what is expressed there
OrganismsSpecies a compound is prepared from
MaterialsSubstances that are not one molecule
AssessmentsRegulatory determinations, transcribed
DiseasesFeatures, genes, and where each sits

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Reference

Evidence

Compounds
Outcomes
Proteins
Interactions
Papers
Articles

Chemistry

Reactions
Reach

Reference layer

Pathways
Processes
Anatomy
Cell types
Organisms
Materials
Assessments
Diseases

Atlas Graph Twin Access

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Catalyst

Computational infrastructure for human biology, built on a provenance-aware knowledge graph. Findings retain their sources; research and simulation are the next layers.

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A reference for what the literature reports. Not medical advice.

Reach

phosphatidyl-L-serine

362,296 routes · scope human · up to 3 steps · built 5 October 2026 · Reactions · API

Inferred

Every route here is a hypothesis drawn from reference reactions (Rhea and Human-GEM), not a finding. Currency species such as water, ATP and NAD(H) never form a step. Evidence key

55 compounds within 3 steps: 2 in 1, 4 in 2, 49 in 3

Does it reach a compound?

Three steps

(17Z)-hexacosenoateReach from here →
Catalysed by PISD, PLA2G10, PLA2G6, PLA2G1B and 15 morecytosol, extracellular spaceOne of 12 routes
(7Z,10Z,13Z,16Z,19Z)-docosapentaenoateReach from here →
Catalysed by PISD, PLA2G10, PLA2G6, PLA2G1B and 15 morecytosol, extracellular spaceOne of 12 routes
(7Z,10Z,13Z,16Z)-docosatetraenoateReach from here →
Catalysed by PISD, PLA2G10, PLA2G6, PLA2G1B and 15 morecytosol, extracellular spaceOne of 12 routes
(5Z,8Z,11Z)-eicosatrienoateReach from here →
Catalysed by PISD, PLA2G10, PLA2G6, PLA2G1B and 15 morecytosol, extracellular spaceOne of 12 routes
tricosanoateReach from here →
Catalysed by PISD, PLA2G10, PLA2G6, PLA2G1B and 15 morecytosol, extracellular spaceOne of 12 routes

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