The Feasibility of Microalgae Dunaliella Identification Based on Conserved Regions of Mitochondrial Cytochrome b and Cytochrome Oxidase Genes

Classification of unicellular algae at species level has not been successfully characterized with common morphological, physiological, and molecular approaches. In this study, the efficiency of two mitochondrial cob and cox1 genes as new molecular targets for the study of the phylogeny relationships was investigated among twenty isolated Dunaliella species from different regions of Iran. First, specific primers were designed based on the conserved regions of the cob and cox1 sequences in Dunaliella species and other microalgae, followed by analysis of PCR products. Based on the analysis of amplification products, some isolates were selected for subsequent RFLP and sequencing processes. Findings revealed that cob gene was not amplified in the isolates, whereas cox1 gene was amplified in B60 , M12 , G3 , and CCAP19 / 18 isolates. RFLP results showed that B60 with 19/18 and G3 with M1.2 had a similar pattern and were grouped in the same clade. Interestingly, the findings on cox1 gene sequencing demonstrated complete congruence with RFLP results. Although the results of this study highlighted the efficiency of cox1 gene in determining the phylogeny relationships between Dunaliella species, further cox1 gene sequences and subsequently PCR and RFLP analyses are required to approve the results. Our results open a new avenue on growing bodies of knowledge regarding the phylogeny relationships of Dunaliella species and could be suitable in taxonomical studies of other microalgae.