Compositional and electrophoretic changes in buffalo milk-fat globule membrane proteins during lactation.
Chemical analyses, polyacrylamide-gel electrophoresis and isoelectric focusing of milk-fat globule membrane proteins (FGMP) obtained from the milk of 2 Murrah buffaloes were done to determine if any change in composition occurred during lactation. Changes in the levels of sialic acid, hexose, hexosamine, N and P were found in the FGMP obtained at different stages of lactation. On the day of parturition, 8 major proteins in FGMP were determined by sodium dodecyl sulphate polyacrylamide-gel electrophoresis whereas 6 major proteins were obtained in FGMP of middle and late lactation milks. Isoelectric focusing of FGMP showed 8-9, 9-13 and 13-16 proteins from colostrum, middle and late lactation milks, respectively and the isoelectric pH of the proteins varied from 5-25 to 7-80, 5-85 to 8-30 and 5-75 to 8-61 respectively.
D000818:Animals; D002020:Buffaloes / Q000502:physiology*; D002241:Carbohydrates; D055598:Chemical Phenomena; D002621:Chemistry; D003126:Colostrum / Q000032:analysis; D004591:Electrophoresis, Polyacrylamide Gel / Q000379:methods; D005260:Female; D007525:Isoelectric Focusing / Q000379:methods; D007743:Labor, Obstetric; D007774:Lactation; D008055:Lipids; D008565:Membrane Proteins; D008892:Milk / Q000032:analysis; D008894:Milk Proteins; D009584:Nitrogen / Q000032:analysis; D010758:Phosphorus / Q000032:analysis; D011247:Pregnancy
D002241:Carbohydrates; D008055:Lipids; D008565:Membrane Proteins; D008894:Milk Proteins; D010758:Phosphorus; D009584:Nitrogen