title: Formation and characterization of iron-binding phosphorylated human-like collagen as a potential iron supplement.
abstract: Iron incorporated into food can induce precipitation and unwanted interaction with other components in food. Iron-binding proteins represent a possibility to avoid these problems and other side effects, as the iron is protected. However, there are several technical problems associated with protein-iron complex formation. In this paper, the iron-binding phosphorylated human-like collagen (Fe-G6P-HLC) was prepared under physiological conditions through phosphorylated modification. One molecule of Fe-G6P-HLC possesses about 24 atoms of Fe. Spectroscopy analysis, differential scanning calorimetry (DSC) and equilibrium dialysis techniques were employed to investigate the characteristics of the Fe-G6P-HLC. The binding sites (nb) and apparent association constant (Kapp) between iron and phosphorylated HLC were measured at nb=23.7 and log Kapp=4.57, respectively. The amount of iron (Fe(2+) sulfate) binding to phosphorylated HLC was found to be a function of pH and phosphate content. In addition, the solubility and thermal stability of HLC were not significantly affected. The results should facilitate the utilization of HLC as a bioactive iron supplement in the food and medical industry and provide an important theoretical evidence for the application of HLC chelates.
authors.affiliation: Shaanxi Key Laboratory of Degradable Biomedical Materials, College of Chemical Engineering, Northwest University, Xi'an 710069, China.
authors.forename: Jianjun
authors.initials: J
authors.lastname: Deng
authors.forename: Fei
authors.initials: F
authors.lastname: Chen
authors.forename: Daidi
authors.initials: D
authors.lastname: Fan
authors.forename: Chenhui
authors.initials: C
authors.lastname: Zhu
authors.forename: Xiaoxuan
authors.initials: X
authors.lastname: Ma
authors.forename: Wenjiao
authors.initials: W
authors.lastname: Xue
mesh_terms: D002152:Calorimetry, Differential Scanning; D003094:Collagen / Q000737:chemistry / Q000378:metabolism*; D004591:Electrophoresis, Polyacrylamide Gel; D019298:Glucose-6-Phosphate / Q000737:chemistry / Q000378:metabolism; D006801:Humans; D006863:Hydrogen-Ion Concentration; D007501:Iron / Q000378:metabolism*; D007700:Kinetics; D010084:Oxidation-Reduction; D010710:Phosphates / Q000032:analysis; D010766:Phosphorylation; D011485:Protein Binding; D012995:Solubility; D013816:Thermodynamics
chemical_list: D010710:Phosphates; D019298:Glucose-6-Phosphate; D003094:Collagen; D007501:Iron
keywords: 2-(N-morpholino)ethanesulfonic acid hydrate; 2-ME; 2-mercaptoethanol; 3-(2-pyridyl)-5,6-bis(4-phenylsulfonic acid)-1,2,4-triazine; 3-(N-morpholino)propanesulfonic acid; BSA; DSC; Ferrozine; G6P; Glucose-6-phosphate; HLC; Human-like collagen; ICP; IDA; K(app); MES; MOPS; Phosphorylation; Protein–iron complex; RH; SC; SDS; TCA; Tris; apparent association constant; bovine serum albumin; differential scanning calorimetry; glucose-6-phosphate; human-like collagen; inductively coupled plasma spectra; iron deficiency anemia; relative humidity; sodium caseinate; sodium dodecyl sulfate; trichloroacetic acid; tris(hydroxymethyl)aminomethane