Isolation and characterization of thiamin-binding protein from chicken egg white.
A thiamin-binding protein was isolated and characterized from chicken egg white by affinity chromatography on thiamin pyrophosphate coupled to aminoethyl-Sepharose. The high specificity of interaction between the thiamin-binding protein and the riboflavin-binding protein of the egg white, with a protein/protein molar ratio of 1.0, led to the development of an alternative procedure that used the riboflavin-binding protein immobilized on CNBr-activated Sepharose as the affinity matrix. The thiamin-binding protein thus isolated was homogeneous by the criteria of polyacrylamide-gel disc electrophoresis, double immunodiffusion and sodium dodecyl sulphate/polyacrylamide-gel electrophoresis, had a mol.wt. of 38,000 +/- 2000 and was not a glycoprotein. The protein bound [14C]thiamin was a molar ratio of 1.0, with dissociation constant (Kd) 0.3 micrometer.
D000818:Animals; D002352:Carrier Proteins / Q000302:isolation & purification*; D002645:Chickens; D002846:Chromatography, Affinity; D004527:Egg Proteins / Q000302:isolation & purification*; D004529:Egg White / Q000032:analysis*; D005779:Immunodiffusion; D012256:Riboflavin; D013831:Thiamine; D013835:Thiamine Pyrophosphate
D002352:Carrier Proteins; D004527:Egg Proteins; D013835:Thiamine Pyrophosphate; D012256:Riboflavin; D013831:Thiamine