Portal de Periódicos da CAPES

Comparative structural studies of human plasma and amniotic fluid fibronectins

1981; Elsevier BV; Volume: 101; Issue: 1 Linguagem: Inglês

10.1016/s0006-291x(81)80040-x

1090-2104

Hema Pande, Jeffrey A. Corkill, Rochelle D. Sailor, John E. Shively,

Cell Adhesion Molecules Research

Human fibronectins from plasma and amniotic fluid were compared in terms of their migrations on SDS and isoelectric focusing gels, immunological reactions, amino acid and carbohydrate compositions, tryptic maps NH2-terminal sequence analysis, and methylation analyses. Both plasma and amniotic fluid fibronectins had the following NH2-terminal sequence: pGlu-Ala-Gln-Gln-Met-Val-Gln-(Cys)-?-?-Ser-Tyr-Ser. It is concluded that the fibronectins studied have closely similar polypeptide chains, but differ significantly in percent total carbohydrate and the relative amounts and types of sugar linkages. Plasma fibronectin has 4.8% carbohydrate with predominantly 2- and 3,6-linked mannose, 4- and 6-linked galactose, 4-linked N-acetylglucosamine, and terminal sialic acid. Amniotic fibronectin has 6.9% carbohydrate with 2,4-linked mannose in addition to 2- and 3,6-linked mannose, 3- and 4-linked galactose (but no 6-linked galactose), 4-linked N-acetyl-glucosamine, and terminal fucose, galactose, mannose, and N-acetylglucosamine in addition to sialic acid.