Interaction of glucose with hemoglobin: a study in aqueous solution and at the air–water interface using the Langmuir–Blodgett technique

Abstract

Here, we report the glycosylation of human adult hemoglobin (Hb) studied in aqueous solution and at the air-water interface by the Langmuir-Blodgett (LB) technique. Pressure-area (π-A) and pressure-time (π-t) measurements show that the concentration of glucose (GLC) and interaction time have an effect on Hb molecular area as well as on surface activity. Solution studies by UV-vis absorption and emission spectroscopy show that the GLC can alter the local conformation of Hb to some extent at the tryptophan and heme residues. CD spectroscopic studies in solution indicate that the α-helix content increases in the presence of GLC at the secondary structure level, which may be the cause of an increased adsorption rate of Hb. Also, secondary structure calculation using FTIR technique in the LB film follows the decrease in α-helix and increase in β-sheet structure as well as the formation of intermolecular aggregates. AFM images of Hb in the LB film indicate the transition from globular to an ellipsoid-like structure of Hb in the presence of GLC. FTIR studies of the LB film support the AFM imaging and the analysis of π-t kinetics. The molecular docking study revealed that Val 1 and Lys 132 are the most favorable docked sites along with some other sites such as Hem 147, Trp 37, Asp 94, Tyr 145, Leu 91, His 143, Glu 43 etc. The overall study may predict the processes of interactions with the increased concentration of GLC on Hb as well as on other long lived proteins.

Study of Anticancer Drugs Interaction with Hemoglobin by Electrochemical Methods and Molecular Docking: Implications towards Anticancer Treatment

“…The peaks at 1745 cm‐1 and 1200 cm‐1 are because of –C=O and −C−O bonds and the other peaks at 1526 cm‐1 and 1685 cm‐1 were attributed to the stretching vibration of −C=C and −C=N bond. All these confirm the formation of SAMs of Hb on the Au wafer [20] …”

“…All these confirm the formation of SAMs of Hb on the Au wafer. [20] The EDS mapping of THb SAMs shows C, N, O, S, and Au like XPS survey scan (Figure S2). It's interesting to note that EDS mapping also reveals the iron (Fe) in the SAMs, which clearly shows that protein structure remains intact during thiolation and further SAMs formation on AuHowever, the XPS spectroscopy doesn't indicate the peak for Fe in the SAMs because Fe is embedded deep inside the Hb pocket [21] and XPS has the limitation of a few nm (10 nm) sensitivity.…”

Effect of Glucose on the Lactoferrin’s Conformation and its Effect on MC 3T3-E1 Cell Proliferation

“…It is also interesting to observe that the CD intensity around 190 nm increased sharply with high glucose concentration. The reason is not clear but this type of CD spectra with a sharp increase in this region has been observed by Prabir Pal et al in hemoglobin [18] and oligopeptides [1].…”

“…A non-linear least square fitting was applied to curve-fitting on the basis of Microcal Origin 7.5 in Levenberg-Marquardt algorithm. It shows that the ellipticity increased, implying an increase in the helical configuration [18], especially when the molar ratio of G: LF was 60.…”

The folic acid metabolite 7,8-dihydrofolate can decrease the interactions of ACE2 with the Wild type, but not with the Beta and Delta SARS-CoV-2 variants: A silico study.

“…Even if the binding energy and stability ligand-protein are high, this does not mean that the ligand modifies the functions of the protein, either by increasing or decreasing its biological activity in a competitive or non-competitive way. For example, glucose has a high affinity to bind as a ligand to hemoglobin; however, although glucose can make some conformational alterations in the structure of hemoglobin [18], it does not play a significant role in the oxygen affinity pattern of diabetics at the concentrations normally found in vivo [19]. For this reason, this research employed autodock vina [15] not only to find the highest affinity poses of FA and some of its metabolites at the ACE2 receptor, but we also used these poses to build an ACE2-metabolite complex to simulate the interactions between RBD and ACE2 in different scenarios using MD.…”