Partial biochemical and immunological characterization of an isolated 52.1 kDa pregnancy-associated glycoprotein charge variant.

Pregnancy-associated glycoproteins (PAGs) are synthesized in the placental cells of ruminants and are detectable in blood, milk, and urine. Many of these proteins have been obtained and characterized from placental extracts by precipitation with 80 % ammonium sulfate. The possibility of purifying PAGs by precipitation with other concentrations of ammonium sulfate remains unexplored.