Introduction: Cyclotella cryptica is a marine diatom recognized as a promising biofuel resource and a model organism for studying diatom physiology and biotechnology. Since lipid biosynthesis in microalgae initiates in plastids, understanding chloroplast genome organization is crucial for advancing biofuel-related research. Objective: The work is focused on sequencing and analyzing the chloroplast genome of C. cryptica and performing a phylogenomic comparative analysis. Methods: The sequencing and annotation of the chloroplast genome of C. cryptica were performed. Comparative phylogenomic analysis was conducted using 27 diatom chloroplast genomes to investigate evolutionary relationships. Results: The chloroplast genome was 129,273 bp in length and contained 132 predicted gene biotypes, including 57 protein-coding genes, 67 tRNA genes, and 8 rRNA genes. Phylogenomic analysis revealed that centric diatoms clustered into a single clade, whereas pennate diatoms formed two distinct clades. Discussion: The conserved clustering of centric diatoms and the clear separation from pennate diatoms reflect established evolutionary patterns within diatoms and highlight the conserved nature of chloroplast genomes in Cyclotella species. Conclusion: These findings enhance understanding of chloroplast genome organization and evolution in Cyclotella and other diatoms and provide valuable genomic insights that may support future research aimed at improving biofuel production.
Singh et al. (Mon,) studied this question.