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This study reports purification and characterization of lipoxygenase protein from mung bean germinating seedlings. Lipoxygenases (LOXs) are key enzymes in seed germination. The purified mung bean LOX has resolved into two peaks by chromatofocusing, one has highest LOX activity with an isoelectric point of 5.84 and the other has lowest LOX activity with an isoelectric point of 5.52. The purified LOX has molecular mass of approximately 97 kDa and showed high activity with linoleic acid than linolenic acid and arachidonic acid. The optimal activity of LOX was observed at pH 6.5 and temperature 35 °C. Far-UV circular dichroism (CD) studies revealed that the purified mung bean LOX possess secondary structural elements with significant α-helix and β-strands. Further, the secondary structure of mung bean LOX was stable up to 60 °C at pH 6.5. Biophysical and chemical properties of the mung bean LOX are similar to the other legume LOXs and may be considered as type-1 LOX.

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The present study was aimed to explore the molecular and structural features of UDP‐N‐acetylglucosamine pyrophosphorylase of Bombyx mori (BmUAP), an essential enzyme for chitin synthesis in insects. The BmUAP cDNA sequence was cloned and expression profiles were monitored during the molting and feeding stages of silkworm larvae. The effect of 20‐hydroxyecdysone (20E) on BmUAP expression, and on silkworm molting was studied, which revealed that 20E regulates its expression. Multiple sequence alignment of various pyrophosphorylases revealed that the residues N223, G290, N327, and K407 of human UAP (PDB ID: 1JV1) were found to be highly conserved in BmUAP and all other eukaryotic UAPs considered for the study. Phylogenetic analysis inferred that the UAPs possess discrete variations in primary structure among different insect Orders while sharing good identity between species of the Order. The structure of BmUAP was predicted and its interactions with uridine triphosphate, N‐acetylglucosamine‐1‐phosphate, and UDP‐N‐acetylglucosamine were analyzed. Virtual screening with a library of natural compounds resulted in five potential hits with good binding affinities. On further analysis, these five hits were found to be mimicking substrate and product, in inducing conformational changes in the active site. This work provides crucial information on molecular interactions and structural dynamics of insect UAPs.

Acetyl-cholinesterase enzyme (AChE) is a known target for identifying potential inhibitors against Alzheimer diseases (AD). Therefore, it is of interest to screen AChE with the CNS-BBB database. An AChE enzyme is a member of hydrolase family is activated by acetylcholine (ACh), so, targeting the AChE enzyme with the potential inhibitor may block the binding of the ACh. In this study we carried out virtual screening of drug-like molecules from Chemical Diversity Database particularly CNS-BBB compounds, to identify potential inhibitors using Glide docking program. Top ranking ten compounds, which have lower Glide Score when compared to known drugs (Tacrine and Galantamine) for AChE. For top three molecules MD simulation was carried out and calculated binding free energy. We report the best binding compounds with AChE compared to known drugs (Taine and Galantamine) for AD. We further document the salient features of their molecular interaction with the known target. Three molecules (1-benzyl-3-(2- hydroxyethyl)-N-[2-(3-pyridyl)ethyl]-3-pyrrolidinecarboxamide, N-{3[benzyl(methyl)amino]propyl}-1,5-dimethyl-4-oxo-4,5-dihydro- 1H-pyrrolo[3,2-c]quinoline-2-carboxamide, and 6-chloro-N-[2-(diethylamino)-2-phenylethyl]-4-oxo-4H-chromene-2-carboxamide) have -196.36, -204.27, -214.40 kJ/mol, binding free energy values respectively which are much lower than values calculated for the reference ligands Tacrine and Galantamine having -119.65 and -142.18 kJ/mol respectively. Thus these molecules can be very novel potential inhibitors against AChE involved in Alzheimer's disease.