title: Studies on the interaction of palmatine hydrochloride with bovine hemoglobin.
abstract: The interaction between bovine hemoglobin (BHb) and palmatine hydrochloride (PMT) was investigated at different temperatures using multispectroscopy, as well as the effect of common metal ions (Ca(2+) , Mg(2+) , Zn(2+) , Cu(2+) , Fe(2+) , Fe(3+) , Co(2+) , Ni(2+) ) on the BHb-PMT system. Results showed that the quenching mechanism of PMT on BHb was a static process. The electrostatic force played an important role in the conjugation reaction between BHb and PMT. The order of magnitude of the binding constants (Ka ) was 10(4) , and the number of binding sites (n) in the binary system was ~ 1. The binding distance (r) was ~ 2.44 nm and the primary binding for PMT was located at β-37 tryptophan in the hydrophobic cavity of BHb. In addition, the Hill's coefficients were ~ 1. Synchronous and circular dichroism spectra revealed that the microenvironment and the conformation of BHb were changed during the binding reaction.
authors.affiliation: Key Laboratory of Medical Chemistry and Molecular Diagnosis, Ministry of Education, College of Chemistry & Environmental Science, Hebei University, Baoding, 071002, People's Republic of China.
authors.forename: Baosheng
authors.initials: B
authors.lastname: Liu
authors.forename: Xiaona
authors.initials: X
authors.lastname: Yan
authors.forename: Shina
authors.initials: S
authors.lastname: Cao
authors.forename: Baohong
authors.initials: B
authors.lastname: Chong
authors.forename: Yunkai
authors.initials: Y
authors.lastname: Lü
mesh_terms: D000818:Animals; D001600:Berberine Alkaloids / Q000737:chemistry*; D001665:Binding Sites; D002417:Cattle; D002942:Circular Dichroism; D006454:Hemoglobins / Q000737:chemistry*; D057927:Hydrophobic and Hydrophilic Interactions; D007700:Kinetics; D011485:Protein Binding; D013056:Spectrophotometry, Ultraviolet; D055672:Static Electricity
chemical_list: D001600:Berberine Alkaloids; D006454:Hemoglobins; C005413:palmatine
keywords: bovine hemoglobin; interaction; metal ions; palmatine hydrochloride