Sukhdev Singh

Structural variations and molten globule state in Arisaema helliborifolium lectin under various treatments as monitored by spectroscopy

Solvent perturbation was used to study variations in structure of Arisaema helliborifolium lectin (AHL) with the help of circular dichroism (CD), intrinsic fluorescence (IF), extrinsic fluorescence, quenching and dynamic light scattering (DLS). AHL was studied under acidic, alkaline and 6 M guanidine hydrochloride (GuHCl) equilibrium states. Three structural states were identified for AHL at different conditions, that are native (N; pH 7.0), molten globule (MG; pH 2.0) and unfolded (U; pH 12.0). CD analysis revealed that 50% of secondary structure of AHL was β-sheet component. A complete loss of secondary structure was observed at GuHCl treatment. The tertiary structural changes as studied by changes in microenvironment of trp residues also suggested a pH induced MG state as in case of CD. Parameter-A analysis pointed at the multi-step unfolding process of lectin under varying pH (pH 1-13). A comparision of CD and IF data further indicated that different pathways were followed for secondary and tertiary structure unfolding. Tryptophans of native AHL were only partially exposed to solvent belonging to Class II. Hydrodynamic diameter (Dh ) measurements of AHL via DLS also confirmed of a pH induced molten globule. A thermally induced molten globule was identified for AHL between 54-60 °C as monitored by DLS. An irreversible thermal denaturation was observed with the formation of a large aggregate. The Dh of AHL at neutral pH was confirmed by transmission electron microscopy (TEM).

Evaluation of galectin-3 genetic variants and lipid profile in RA patients in North Indian population

Results The genotypic distribution of +191(A/C) showed significant differences between patients and controls (odds ratio = 1.9552, 95% CI = 1.0461-3.6542, p 0.05 ). RA patients were found to be dyslipidemic as indicated by the significantly higher atherogenic index as compared to controls (p<0.01). Conclusion Galectin-3 may play an important role in pathogenesis of RA.

Assessment of MBL2 gene polymorphism and lipid peroxidation in Chronic Obstructive Pulmonary Disease (COPD)

Background Chronic Obstructive Pulmonary Disease (COPD) is fourth leading cause of death worldover. It has been defined as a state characterized by airflow obstruction due to inflammatory reaction. Various innate and adaptive immune system molecules are involved in pathogenesis of COPD. Mannose-binding lectin (MBL) is a Ca dependent collagenous lectin which intervene immune response by inhibiting pathogen activity. Point mutations, in codon 54 and 57 of exon 1 of the MBL2 have been reported to affect the serum levels of MBL. Aim of the present study was to investigate the association of MBL2 gene polymorphism with severity and susceptibility towards COPD.

Effect of growth regulators on quality of ber (Zizyphus mauritiana Lamk) cv. Umran.

There is huge potential to improve market acceptability of ber with application of growth regulators. Significant increase in fruit size traits i.e. fruit length, breadth, weight and volume was recorded with application of NAA 30 ppm. The palatability rating of fruits in terms of taste, colour and texture of fruit was recorded maximum with application of GA3 50 ppm. For the stone related traits, the maximum reduction in stone breadth and percentage was recorded with NAA 30 ppm. There was no significant variation in stone length and weight with growth regulators.