Comparative characterization of CRTISO from D. salina and D. bardawil

Dunaliella, known for its high salt tolerance and photosynthetic efficiency, plays a significant role in industrial and food production. This study presents a comparative analysis of the lycopene biosynthesis pathway in Dunaliella salina and Dunaliella bardawil. Genetic material from both species was extracted and expressed in a bacterial system, followed by HPLC, molecular docking, and phylogenetic analysis. The all-trans-lycopene content in the DsCRT strain was 1.26 ± 0.03 mg/g DCW, higher than that of the DbCRT strain. Molecular docking analysis showed that the binding affinity between DsCRTISO and the substrate was -11.18 kcal/mol, which was lower than the binding affinity of DbCRTISO (-10.08 kcal/mol), revealing that the catalytic activity of DsCRTISO was greater than that of DbCRTISO. Phylogenetic analysis confirmed a close relationship between D. salina and D. bardawil. HPLC showed that D. bardawil accumulate minimal β-carotene, likely due to the failure of specific gene regulatory mechanisms, despite sharing conserved CRTISO domains with D. salina. This study demonstrates that lycopene metabolism enzyme activity in D. salina is significantly higher than in D. bardawil, offering potential for industrial lycopene production.