Characterizing the mono- and triacylglycerol lipase (MAGL and TAGL) genes from pearl millet (Pennisetum glaucum L.) and elucidating their dynamics with biochemical traits linked with rancidity
摘要
We cloned two variants of lipase gene—MAGL and TAGL from pearl millet. Lipase showed negative correlation with antioxidants and total phenolics. FAA can be used as marker for rancidity.
AbstractPearl millet is considered as “Nutri-cereal” due to its rich nutrient profile. Low keeping quality of the flour due to rancidity is one of the major problems in pearl millet. Lipases are a group of enzymes that produces free fatty acids that ultimately leads to rancidity. Very few lipases have been identified and characterized from pearl millet. Here, we have identified 2039 transcripts of lipases from pooled samples (leaf, stem and developing grains) of pearl millet using de novo transcriptomic approach and predicted 05 full length lipase variants. Further, we cloned 02 lipase genes—monoacylglycerol lipase (MAGL, acc. no. MZ590564) and triacylglycerol lipase (TAGL, acc. no. MZ590565) of 1.5 kb each from pearl millet cv. Pusa-1201. Conserved domain search analysis showed the presence of catalytic triad [GXSXG] near the active site which is signature domain of lipase family of proteins. MAGL showed maximum expression in PC-701 and TAGL in Pusa-1201 during mealy-ripe growth stage of endospermic tissue. Abundance of transcripts of both the lipases was observed in the harvested grains of PC-701. We observed negative correlation between the lipase activity and accumulation of antioxidants like total phenolic content (TPC), tannin, and total antioxidant potential (TAP). Free amino acid and reducing sugar were observed as potential markers for accessing the intensity/extent of rancidity in pearl millet flour. Thus, there is need to explore and characterize the lipase variants to connect the missing dots in rancidity pathway and to use it in genome editing using the CRISPR/Cas9 approach for the development of pearl millet lines free of off-odor and flour rancidity.