Amaranth (Amaranthushypochondriacus) Vicilin Subunit Structure

ALEJANDRA QUIROGA; E. NORA MARTINEZ; HELENE ROGNIAUX; AUDREY GEAIRON; M. CRISTINA AÑÓN

JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY

AMER CHEMICAL SOC

Lugar: Washington DC; Año: 2010 vol. 58 p. 12957 - 12963

0021-8561

The7S-globulin fraction is a minor component of the amaranth storage proteins. The present work provides new information about this protein. Theamaranth7S-globulin or vicilin presented a sedimentation coefficient of 8.6 ± 0.6 S and was composed of main subunits of 66, 52, 38,and 6kDa. On the basis of mass spectrometry (MS) analysis of tryptic fragments, the 52, 38, and16 kDa subunits presented sequence homology with sesame vicilin, whereas the 66 kDa subunit showed sequence similarity with a putative vicilin. Several characteristics of the 66 kDa subunit were similar to members of the convicilin family. Results support the hypothesis that the 7S-globulin molecules are composed of subunits coming from at least two gene families with primary products of 66 and 52 kDa, respectively. According to the present information, amaranth vicilin may be classified into the vicilin group that includes pea, broadbean, and sesame vicilins, among others.