The full energy pathway is distributed across multiple organisms.
Cross-feeding and syntrophy make it necessary to classify some energetic systems at the consortium level rather than attributing the whole process to one species. (PubMed Central (PMC))
Operational definition
Collective metabolic architecture.
A complete metabolic transformation whose necessary steps are distributed among multiple organisms, such that the full pathway exists only at the level of the interacting consortium.
Unlike simple facultative cross-feeding, consortium-level metabolism makes the multi-organism system the appropriate unit for describing the overall pathway, energy yield, and products. Cross-feeding transfers metabolites among organisms; syntrophy more specifically couples partners through thermodynamic interdependence, while acquired phototrophy can result from retained symbionts or stolen plastids. (PubMed Central (PMC))