Sugawara G, Inoue R, Watanabe K, Ohtsuka H, Orino K
Veterinary Biochemistry Laboratory, School of Veterinary Medicine, Kitasato University, Aomori 034-8628, Japan.
J Dairy Sci. 2009 Aug;92(8):3810-4. doi: 10.3168/jds.2008-1948.
Commercial bovine milk alpha-casein, but not beta- and kappa-caseins, bound to bovine spleen ferritin, as determined by an immunoassay for ferritin. In contrast, alpha-casein did not bind to apoferritin. The binding of alpha-casein to bovine spleen ferritin was strongly inhibited by increasing ionic strength by the addition of 0.5 M (NH(4))(2)SO(4). The addition of alpha-casein to a known amount of bovine spleen ferritin resulted in significantly lower recovery (78-80%) of added ferritin, although beta- and kappa-caseins showed little inhibitory effect in the ferritin immunoassay. These results indicate that bovine alpha-casein is a specific ferritin-binding protein that may inhibit milk ferritin immunoassay.
通过铁蛋白免疫测定法测定发现，市售牛乳α-酪蛋白能与牛脾脏铁蛋白结合，而β-酪蛋白和κ-酪蛋白则不能。相比之下，α-酪蛋白不与脱铁铁蛋白结合。添加0.5M硫酸铵增加离子强度可强烈抑制α-酪蛋白与牛脾脏铁蛋白的结合。向已知量的牛脾脏铁蛋白中添加α-酪蛋白，导致添加的铁蛋白回收率显著降低（78 - 80%），尽管β-酪蛋白和κ-酪蛋白在铁蛋白免疫测定中几乎没有抑制作用。这些结果表明，牛α-酪蛋白是一种特异性铁蛋白结合蛋白，可能会抑制牛奶铁蛋白免疫测定。
