Network reduction in metabolic pathway analysis: Elucidation of the key pathways involved in the photoautotrophic growth of the green alga Chlamydomonas reinhardtii

► We propose a network reduction approach for metabolic pathway analysis. ► We apply it to study photoautotrophic growth of Chlamydomonas reinhardtii. ► We analyze a set of flux vectors corresponding to changing light influx. ► We identify key pathways by decomposing these flux vectors into elementary modes. ► We compare pathway activity changes to adaptation in cellular energetics.