Isolation and properties of glycosylated pig prolactin (G-PRL)

Isolation and properties of glycosylated pig prolactin (G-PRL)--Crude prolacting was received via extraction from lyophilized hypophyses with acidic 70% acetone, and then by protein precipitation via increasing acetone concentration in the extract to 92%. Received precipitate was dissolved in 0.1 M acetic acid and prolactin was precipitated in the isoelectric point at the pH = 4.97. Prolactin precipitate was dissolved in phosphate buffer pH = 7.50 and adsorbed on the DEAE-Sephadex column, and then eluated with linear gradient at NaCl concentration range 0.00-0.40 M. Prolactin with molecular mass 24.0 kD was eluated at NaCl concentration 0.19-0.25 M. Using gel filtration method on Sephadex G-100 glycosylated prolactin was divided into 2 fractions with molecular mass equal--55.8 and 17.4 kD. Both 24.0 kD--prolactin and its glycosylated form were characterized by high biological activity. Glycosylated prolactin contains among others mannose and fucose.