title: Isolation and characterization of beta- and gamma-caseins from horse milk.
abstract: Three groups of casein components were isolated from horse milk. Group I is almost insoluble at acid and neutral pH, and is rather heterogeneous on alkaline gels with or without sodium dodecyl sulphate. Group II shows strong similarity to beta-casein from other species, as concluded from its amino acid composition and its N- and C-terminal sequences. This group consists of five electrophoretically distinguishable  forms, all containing ester phosphate groups but no carbohydrate. Group III is composed of C-terminal fragments of the beta-like (group II) fraction and probably arises from the action of a plasmin-like enzyme present in horse milk. It does not contain phosphate or carbohydrate. Homology of this group with bovine gamma-caseins is demonstrated. Both beta- and gamma-like caseins are more soluble at 4 degrees C than at room temperature.
mesh_terms: D000135:Acid Phosphatase; D000595:Amino Acid Sequence; D000596:Amino Acids / Q000032:analysis; D000818:Animals; D002364:Caseins / Q000302:isolation & purification*; D002417:Cattle; D012085:Chymosin; D004591:Electrophoresis, Polyacrylamide Gel; D004592:Electrophoresis, Starch Gel; D005260:Female; D005341:Fibrinolysin; D006736:Horses; D008892:Milk / Q000032:analysis*; D008970:Molecular Weight
chemical_list: D000596:Amino Acids; D002364:Caseins; D000135:Acid Phosphatase; D005341:Fibrinolysin; D012085:Chymosin