TY - JOUR
T1 - Binding of vanadium to human serum transferrin - voltammetric and spectrometric studies
AU - Azevedo, Cristina G.
AU - dos Santos, Margarida M.C.
AU - Santos, Marino F.A.
AU - Santos-Silva, Teresa
AU - Doutch, James
AU - Fernandes, Luz
AU - Santos, Hugo M.
AU - Capelo, José L.
AU - Pessoa, João Costa
AU - Correia, Isabel
N1 - info:eu-repo/grantAgreement/FCT/5876/147266/PT#
info:eu-repo/grantAgreement/FCT/5876/147216/PT#
info:eu-repo/grantAgreement/FCT/3599-PPCDT/126438/PT#
info:eu-repo/grantAgreement/FCT/SFRH/SFRH%2FBD%2F77894%2F2011/PT#
info:eu-repo/grantAgreement/FCT/5876/147258/PT#
info:eu-repo/grantAgreement/FCT/5876/147218/PT#
sem pdf conforme despacho.
Fundação para a Ciência e Tecnologia (FCT), RECI/QEQMED/0330/2012, PTDC/QEQ-MED/1902/2014 and grant BPD/CQE-2017-029 to M.F.A.S) and programme FCT Investigator: IF/00100/2013 (I.C.) and IF/00007/2015 (H.M.S.).
co-financed by the ERDF under the PT2020 Partnership Agreement (POCI-01-0145-FEDER-007728).
co-financed by the ERDF under the PT2020 Partnership Agreement (POCI-01-0145-FEDER-007265).
PY - 2018/3/1
Y1 - 2018/3/1
N2 - Previous studies generally agree that in the blood serum vanadium is transported mainly by human serum transferrin (hTF). In this work through the combined use of electrochemical techniques, matrix-assisted laser desorption/ionization time of flight (MALDI-TOF) mass spectrometry and small-angle X-ray scattering (SAXS) data it is confirmed that both VIV and VV bind to apo-hTF and holo-hTF. The electrochemical behavior of solutions containing vanadate(V) solutions at pH = 7.0, analyzed by using two different voltammetric techniques, with different time windows, at a mercury electrode, Differential Pulse Polarography (DPP) and Cyclic Voltammetry (CV), is consistent with a stepwise reduction of VV → VIV and VIV → VII. Globally the voltammetric data are consistent with the formation of 2:1 complexes in the case of the system VV-apo-hTF and both 1:1 and 2:1 complexes in the case of VV-holo-hTF; the corresponding conditional formation constants were estimated. MALDI-TOF mass spectrometric data carried out with samples of VIVOSO4 and apo-hTF and of NH4VVO3 with both apo-hTF and holo-hTF with V:hTF ratios of 3:1 are consistent with the binding of vanadium to the proteins. Additionally the SAXS data suggest that both VIVOSO4 and NaVVO3 can effectively interact with human apo-transferrin, but for holo-hTF no clear evidence was obtained supporting the existence or the absence of protein-ligand interactions. This latter data suggest that the conformation of holo-hTF does not change in the presence of either VIVOSO4 or NH4VVO3. Therefore, it is anticipated that VIV or VV bound to holo-hTF may be efficiently up-taken by the cells through receptor-mediated endocytosis of hTF.
AB - Previous studies generally agree that in the blood serum vanadium is transported mainly by human serum transferrin (hTF). In this work through the combined use of electrochemical techniques, matrix-assisted laser desorption/ionization time of flight (MALDI-TOF) mass spectrometry and small-angle X-ray scattering (SAXS) data it is confirmed that both VIV and VV bind to apo-hTF and holo-hTF. The electrochemical behavior of solutions containing vanadate(V) solutions at pH = 7.0, analyzed by using two different voltammetric techniques, with different time windows, at a mercury electrode, Differential Pulse Polarography (DPP) and Cyclic Voltammetry (CV), is consistent with a stepwise reduction of VV → VIV and VIV → VII. Globally the voltammetric data are consistent with the formation of 2:1 complexes in the case of the system VV-apo-hTF and both 1:1 and 2:1 complexes in the case of VV-holo-hTF; the corresponding conditional formation constants were estimated. MALDI-TOF mass spectrometric data carried out with samples of VIVOSO4 and apo-hTF and of NH4VVO3 with both apo-hTF and holo-hTF with V:hTF ratios of 3:1 are consistent with the binding of vanadium to the proteins. Additionally the SAXS data suggest that both VIVOSO4 and NaVVO3 can effectively interact with human apo-transferrin, but for holo-hTF no clear evidence was obtained supporting the existence or the absence of protein-ligand interactions. This latter data suggest that the conformation of holo-hTF does not change in the presence of either VIVOSO4 or NH4VVO3. Therefore, it is anticipated that VIV or VV bound to holo-hTF may be efficiently up-taken by the cells through receptor-mediated endocytosis of hTF.
KW - Binding constants
KW - MALDI-TOF
KW - SAXS
KW - Transferrin
KW - Vanadium
KW - Voltammetric studies
UR - http://www.scopus.com/inward/record.url?scp=85041491264&partnerID=8YFLogxK
U2 - 10.1016/j.jinorgbio.2017.12.012
DO - 10.1016/j.jinorgbio.2017.12.012
M3 - Article
C2 - 29355752
AN - SCOPUS:85041491264
SN - 0162-0134
VL - 180
SP - 211
EP - 221
JO - Journal of Inorganic Biochemistry
JF - Journal of Inorganic Biochemistry
ER -