The effects of Pr3+, Gd3+ ions on the H-1 NMR spectrum of anticoagulation factor (ACF) from snake venom were investigated. It was observed that the quartet peaks at delta 4.16 and the triplet peaks at delta 1.37 are g...The effects of Pr3+, Gd3+ ions on the H-1 NMR spectrum of anticoagulation factor (ACF) from snake venom were investigated. It was observed that the quartet peaks at delta 4.16 and the triplet peaks at delta 1.37 are gradually broadened with the increase of Pr3+ ion content, but the broadening effects of Pr3+ ion on the two single peaks at delta 1.99 and delta 2.29 were not observed obviously, and the obvious chemical shifts of all peaks induced by Pr3+ were not found. Two peaks contributed to alphaH and PH of the Ala side chain in ACF are broadened by Gd3+ ion, while two single peaks at delta 2.29 and delta 2.29 are not affected basically by Gd3+ ion. This result proves that the distance between the Ca2+-binding site in ACF and aH or PH of the Ala side chain in ACF is shorter than that between the Ca2+-binding site in ACF and proton in Met residue.展开更多
文摘The effects of Pr3+, Gd3+ ions on the H-1 NMR spectrum of anticoagulation factor (ACF) from snake venom were investigated. It was observed that the quartet peaks at delta 4.16 and the triplet peaks at delta 1.37 are gradually broadened with the increase of Pr3+ ion content, but the broadening effects of Pr3+ ion on the two single peaks at delta 1.99 and delta 2.29 were not observed obviously, and the obvious chemical shifts of all peaks induced by Pr3+ were not found. Two peaks contributed to alphaH and PH of the Ala side chain in ACF are broadened by Gd3+ ion, while two single peaks at delta 2.29 and delta 2.29 are not affected basically by Gd3+ ion. This result proves that the distance between the Ca2+-binding site in ACF and aH or PH of the Ala side chain in ACF is shorter than that between the Ca2+-binding site in ACF and proton in Met residue.
