Basis of genetic adaptation to heavy metal stress in the acidophilic green alga Chlamydomonas acidophila

•The most complete published transcriptome of C. acidophila increase the genomic information available for this species and extremophilic eukaryotes.•A set of identified orthologous genes between eight species is a valuable source for comparative evolutionary studies on green algae from different habitats.•New insights on the adaptation mechanisms used by algae to thrive in acidic environments.•Candidate genes of potential interest for engineering heavy metal tolerance in green algae for environmental and economic applications.