Survey of the anaerobic metabolism of various laboratory wild-type Chlamydomonas reinhardtii strains

Given the wide diversity of wild-type Chlamydomonas reinhardtii genotypes due to the presence of genes belonging to either of different gene haplotypes (Gallaher, S.D., Fitz-Gibon, S.R., Glaesener, A.G., Pellegrini, M. and Merchant, S.S. 2015, The Plant Cell, doi 10.1105/tpc.15.00508), we performed a phenotypic characterization of representative strains whose anaerobic metabolism has been studied either by our laboratory or by others. Our results reveal major differences in the levels of H2 production and in the pattern of fermentative metabolite generation, highlighting the activation of different fermentative pathways in each organism. Some of the differences could be attributed to differences in the haplotypes of the various genes involved in these pathways. Moreover, the nature of the metabolites produced under dark anaerobiosis versus sulfur-deprivation-induced anaerobiosis are different in the analyzed strains, emphasizing the differential activation of metabolic pathways promoted under the two conditions and highlighting the importance of utilizing appropriate C. reinhardtii strains for addressing specific research questions.