Isolation and partial caracterization of a new lipo-glico-carotenoprotein from Pomacea scalaris (Mollusca, Ampullariidae)

ITUARTE, S; DREÓN, MS; POLLERO, RJ; HERAS, H

Pinamar, BsAs.

Congreso; XLI Congreso de la Sociedad Argentina de Investigaciones Bioquímicas; 2005

Sociedad Argentina de Investigaciones Bioquímicas

Carotenoid-binding proteins are commonly found in invertebrates. They have a variety of functions, giving many of the egg, ovaries and exoskeleton colors. In mollusks they have been described in eggs and reproductive system of a few species. Within the Ampullariidae, our group has characterized the main lipovitellin of Pomacea canaliculata, ovorubin, which is a multifunctional glyco-lipo-carotenoprotein. Ovorubin not only serves as an egg reserve protein, but also gives photo protection and antioxidant defenses for the developing embryo. In the present work we partially characterized a perivitellin of P. scalaris, a close relative to P. canaliculata. Scalarin was isolated from egg homogenates by ultracentrifugation, and purified by size exclusion chromatography. Protein moiety was characterized by PAGGE, determining its glycosilation and MW. Lipids were extracted with a chloroform-methanol mixture, and analyzed by TLC-FID. Carotenoid extracts were analyzed by HPTLC. Scalarin was found to be the major egg glyco-lipo-carotenoprotein with characteristics of a VHDL (d=1,26 g/ml) representing XX% by wt. of the total protein of the egg perivitellus. The particle has a MW of 380 kDa, and it is composed of three subunits of ca. 35, 28, and 24 kDa. Lipids represent XX%. Carotenoid analysis revealed the presence of free and sterified astaxanthin, in a pattern similar to that of ovorubin