Albumin as a prospective carrier of the nitrosyl iron complex with thiourea and thiosulfate ligands under aerobic conditions

Abstract

High molecular weight dinitrosyl iron complexes (DNICs) are formed in living systems and are a stable depot of nitrogen monoxide (NO). In this work, using experimental and theoretical methods, we...

A nitrosyl iron complex with 3.4-dichlorothiophenolyl ligands: synthesis, structures and its reactions with targets – carriers of nitrogen oxide (NO) in vivo

“…Therefore, in all experiments with the Griess reaction in the buffer and model biological systems, we took the initial concentration of 2 × 10 −4 M. In this case, (2 ± 1) μM nitrites immediately accumulate in the experimental cuvette, which is lower than that for previously studied NICs. 59–61…”

“…The formation of a high-molecular-weight product leads to effective fluorescence quenching ( K = 2 × 10 5 M −1 , R 0 = 24.0 Å); the fluorescence of Trp134 is more strongly quenched, as for all previously considered NICs. 59,61,65…”

“…Dalton Transactions centration of 2 × 10 −4 M. In this case, (2 ± 1) μM nitrites immediately accumulate in the experimental cuvette, which is lower than that for previously studied NICs. [59][60][61] It is interesting to note that the NO-donor activity of this compound increases when it is stored in DMSO. It has been established that the concentration of nitrites formed in an aqueous solution upon the introduction of a complex stored in DMSO for 3.3 hours is 5-6 times higher than the concentration of nitrites in a freshly prepared solution (Fig.…”

“…The presence of a maximum in the region of 390 nm is characteristic of mononuclear NICs with aliphatic thioligands. 63,64 Previously, we have shown 59,61,65 that the decomposition products of the NICs (dinitrosyl fragments and oxygen-containing nitrosyls) are able to coordinate with the free SH-group of the protein. Moreover, it was found by molecular docking that the His39 amino acid residue will also be involved in binding.…”

“…Similar spectra were observed earlier at 77 K and room temperature for the albumin-bound NICs. 22,65,66 The concentration of paramag-netic centers is 0.76 mM; after a day, their concentration does not change. The observed anisotropy of the g-factor indicates that the rotation of paramagnetic centers is strongly inhibited due to their binding to the albumin molecule.…”