title: Identification of the major mannose-binding proteins from chicken egg yolk and chicken serum as immunoglobulins.
abstract: Chicken egg yolk contains a mannose-binding protein that could be purified with a modification of the procedure of affinity chromatography and gel filtration used for chicken serum mannose-binding protein. The yolk protein was indistinguishable from the serum protein with respect to apparent molecular masses (169 +/- 7 kDa), subunits (74 kDa and 27 kDa, in approximately 1:1 ratio) produced after denaturation in the presence of mercaptoethanol, immunoreactivity with antibody against the chicken serum mannose-binding protein, amino acid composition, pH optimum for binding, calcium independence of binding, sugar-binding specificity, and specific-binding activity. Moreover, the chicken mannose-binding proteins cross-reacted with gamma-chain-specific antibody against chicken IgG. The binding proteins were identified as IgGs by several other criteria: identical electrophoresis pattern when subjected to reducing and nonreducing NaDodSO4/polyacrylamide gel electrophoresis, cochromatography on a Fractogel TSK HW-55(F) column, similar amino acid composition, and isolation of mannose-binding protein from purified serum IgG at a yield comparable to whole serum. These results support the notion that the mannose-binding proteins from the chicken serum and egg yolk are similar, if not identical, and are a subset of chicken IgG.
authors.forename: K Y
authors.initials: KY
authors.lastname: Wang
authors.forename: C A
authors.initials: CA
authors.lastname: Hoppe
authors.forename: P K
authors.initials: PK
authors.lastname: Datta
authors.forename: A
authors.initials: A
authors.lastname: Fogelstrom
authors.forename: Y C
authors.initials: YC
authors.lastname: Lee
mesh_terms: D000596:Amino Acids / Q000032:analysis; D000818:Animals; D002240:Carbohydrate Sequence; D002352:Carrier Proteins / Q000378:metabolism*; D002645:Chickens; D004527:Egg Proteins / Q000378:metabolism*; D004529:Egg White / Q000032:analysis; D004530:Egg Yolk / Q000378:metabolism*; D007074:Immunoglobulin G / Q000378:metabolism*; D046911:Macromolecular Substances; D008358:Mannose / Q000378:metabolism*; D037241:Mannose-Binding Lectins; D008970:Molecular Weight
chemical_list: D000596:Amino Acids; D002352:Carrier Proteins; D004527:Egg Proteins; D007074:Immunoglobulin G; D046911:Macromolecular Substances; D037241:Mannose-Binding Lectins; D008358:Mannose