Phylogenomic Study of Lipid Genes Involved in Microalgal Biofuel Production—Candidate Gene Mining and Metabolic Pathway Analyses

Abstract

Optimizing microalgal biofuel production using metabolic engineering tools requires an in-depth understanding of the structure-function relationship of genes involved in lipid biosynthetic pathway. In the present study, genome-wide identification and characterization of 398 putative genes involved in lipid biosynthesis in Arabidopsis thaliana Chlamydomonas reinhardtii, Volvox carteri, Ostreococcus lucimarinus, Ostreococcus tauri and Cyanidioschyzon merolae was undertaken on the basis of their conserved motif/domain organization and phylogenetic profile. The results indicated that the core lipid metabolic pathways in all the species are carried out by a comparable number of orthologous proteins. Although the fundamental gene organizations were observed to be invariantly conserved between microalgae and Arabidopsis genome, with increased order of genome complexity there seems to be an association with more number of genes involved in triacylglycerol (TAG) biosynthesis and catabolism. Further, phylogenomic analysis of the genes provided insights into the molecular evolution of lipid biosynthetic pathway in microalgae and confirm the close evolutionary proximity between the Streptophyte and Chlorophyte lineages. Together, these studies will improve our understanding of the global lipid metabolic pathway and contribute to the engineering of regulatory networks of algal strains for higher accumulation of oil.

Agrigenomics for Microalgal Biofuel Production: An Overview of Various Bioinformatics Resources and Recent Studies to Link OMICS to Bioenergy and Bioeconomy

“…It is likely that the dearth of algal genomic data as compared to higher plants has contributed to the present status of limited pathway databases and web resources. However, integration of plant lipid pathway databases in comparative genomic analyses might reveal the homologous enzymes responsible for lipid biosynthesis and regulation in microalgae (Beisson et al, 2003;Misra et al, 2012). In this section, we provide a brief overview of the various databases and bioinformatics tools with particular reference to explore lipid metabolic pathways in microalgae, along with few selected plant-specific databases relevant for microalgal biofuel research.…”

Increasing Microbial Biofuel Production by In-silico Comparative Genomic Studies

“…These methods at organism and functional level can reduce years of wet lab experimentation by narrowing down the huge number of genes and even pinpoint the most desirable ones. Optimizing microalgal biofuel production using metabolic engineering tools requires an in-depth understanding of the structure-function relationship of genes involved in lipid biosynthetic pathway [12].…”

“…Later, we obtained evidence that Volvox carteri, which is a species of colonial green algae [19], has also been studied for lipid production and is a homolog of C. reinhardtii [12]. Verification of this observation by a phylogenetic analysis between the said organisms and Chlamydomonas reinhardtii (Fig.…”

“…The literature survey showed that Arabidopsis thaliana, Ostreococcus lucimarinus, Ostreococcus tauri and Volvox carteri were homologous to Chlamydomonas reinhardtii [12]. To confirm this, we carried out a phylogenetic analysis.…”

“…A selection of proteins involved in the regulation of lipid synthesis was shortlisted [12]. The shortlisted protein sequences were downloaded from the UniProt database [13].…”