Integrating an algal β-carotene hydroxylase gene into a designed carotenoid-biosynthesis pathway increases carotenoid production in yeast

Abstract The algal β-carotene hydroxylase gene Crchyb from Chlamydomonas reinhardtii , Czchyb from Chlorella zofingiensis , or Hpchyb from Haematococcus pluvialis and six other carotenoid-synthesis pathway genes were co-integrated into the genome of a yeast host. Each of these three algal genes showed a higher efficiency to convert β-carotene to downstream carotenoids than the fungal genes from Phaffia rhodozyma . Furthermore, the strain with Hpchyb displayed a higher carotenoid productivity than the strains integrated with Crchyb or Czchyb , indicating that Hpchyb is more efficient than Crchyb and Czchyb . These results suggest that β-carotene hydroxylase plays a crucial role in the biosynthesis of carotenoids.