The binding behavior of itraconazole with hemoglobin: studies from multi-spectroscopic techniques.
The interactions between hemoglobin (Hb) and itraconazole (ITZ) are investigated in details using UV-vis spectra, circular dichroism spectroscopy, steady state fluorescence, three-dimensional fluorescence spectra, synchronous fluorescence and time-resolved fluorescence spectra at molecular level. The UV-vis studies represent that ITZ can access into heme group and lead to it explored in aqueous medium. CD spectra suggest ITZ could combine with amino acid residues in polypeptide chain and cause a partial unfolding of Hb (reducing of the α-helix content). Steady state fluorescence/synchronous fluorescence (taking into account inner filter effects) and three-dimensional fluorescence/time-resolved fluorescence spectroscopy results reveal that ITZ alters polarity and conformation around the fluorophore molecule. The interaction processes are static quenching mechanisms. The negative of ΔH(0) and ΔS(0) indicate that hydrogen bonds and van der Waals are the main force.
Department of Geriatrics, First Affiliated Hospital of Nanjing Medical University, 300 Guangzhou Road, Nanjing, Jiangsu Province, China.
Yuanfan
Y
Wu
Department of Geriatrics, First Affiliated Hospital of Nanjing Medical University, 300 Guangzhou Road, Nanjing, Jiangsu Province, China.
Weiding
W
Cui
Department of Geriatrics, First Affiliated Hospital of Nanjing Medical University, 300 Guangzhou Road, Nanjing, Jiangsu Province, China. Electronic address: zhousmco@aliyun.com.
Suming
S
Zhou
State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, China. Electronic address: mfnjnu@126.com.
Fei
F
Ma
D000818:Animals; D000935:Antifungal Agents / Q000378:metabolism*; D002417:Cattle; D002942:Circular Dichroism; D006454:Hemoglobins / Q000737:chemistry / Q000378:metabolism*; D017964:Itraconazole / Q000378:metabolism*; D011485:Protein Binding; D017433:Protein Structure, Secondary / Q000187:drug effects; D058767:Protein Unfolding / Q000187:drug effects; D013050:Spectrometry, Fluorescence; D013056:Spectrophotometry, Ultraviolet; D013816:Thermodynamics
D000935:Antifungal Agents; D006454:Hemoglobins; D017964:Itraconazole
CD spectroscopy; Fluorescence spectroscopy; Hemoglobin; Itraconazole; UV–vis spectra