Abstract Native lactoferrin (U-Lf) forms predominantly soluble complexes with native (U-WPI) or denatured (H-WPI) whey protein isolate proteins at all mixing ratios, forming weakly turbid solutions and charge neutrality at a Lf to WPI ratio of 2.0, w/w. This may be due to an asymmetrical charge spacing between the two interacting protein species, resulting in a weak interaction and soluble complexes. Denatured lactoferrin (H-Lf) strongly interacts with U-WPI or H-WPI, with highly turbid solutions formed at certain ratios. For H-Lf/U-WPI, maximum turbidity and charge neutrality was observed at a ratio of 2.0, w/w, with turbidity decreasing and zeta potential increasing either side of this ratio. H-Lf/H-WPI formed highly turbid solutions and neutral complexes at a ratio of about 2.0, w/w; however, the solution remained highly turbid at higher ratios despite the increasing charges of the complexes. Denaturation may make the proteins less flexible allowing desolvation leading to precipitation rather than coacervation.

中文翻译：

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乳清分离蛋白和乳铁蛋白之间的自发相互作用：热变性的影响

摘要 天然乳铁蛋白 (U-Lf) 在所有混合比例下与天然 (U-WPI) 或变性 (H-WPI) 乳清蛋白分离蛋白形成主要可溶性复合物，在 Lf 与 WPI 的比例为 2.0 时形成弱混浊溶液和电荷中性，w/w。这可能是由于两种相互作用的蛋白质种类之间的电荷间隔不对称，导致相互作用较弱和可溶性复合物。变性乳铁蛋白 (H-Lf) 与 U-WPI 或 H-WPI 强烈相互作用，以特定比例形成高度混浊的溶液。对于 H-Lf/U-WPI，在 2.0 w/w 的比率下观察到最大浊度和电荷中性，在该比率的任一侧浊度降低且 zeta 电位增加。H-Lf/H-WPI 以约 2.0 w/w 的比例形成高度混浊的溶液和中性复合物；然而，尽管复合物的电荷增加，但溶液在较高比例下仍然高度混浊。变性可能会使蛋白质不太灵活，从而导致去溶剂化导致沉淀而不是凝聚。