Cellular localization of the invertase ,proteinaceous inhibitor and lectin from potato tubers

ISLA MI, LEAL DP, VATTUONE, M.A., SAMPIETRO, A.R

PHYTOCHEMISTRY

PERGAMON-ELSEVIER SCIENCE LTD

Lugar: Amsterdam; Año: 1992 vol. 31 p. 1115 - 1118

0031-9422

activity of the acid ~-~fructofuranoside fructohydrolase from Sowing tuberosum is thought to bemodulated by a proteinaceous inhibitor. However, the invertase is also inhibited by the S. tuberosum agglutinin, andfructose is able to modulate the enzyme activity in vitro, These facts cast doubt on the physiological role of theproteinaceous inhibitor. The present paper shows that the soluble acid invertase from S. tub~osum and most of the cellsucrose occur in vacuoles together with fructose and glucose. The proteinaceous inhibitor and the lectin were foundtogether in the partially digested cell wall. From these results an in vivo action of the proteinaceous inhibitor upon thesoluble acid invertase is unlikely.