PEROXIDASE-REGULATED ELONGATION OF SEGMENTS FROM PEANUT HYPOCOTYLS

Alterations of isoperoxidases were studied in 1.0 cm segments from 3-day-peanut-seedling (Arachis hypogaea L.) hypocotyls as they were cultured on Linsmayer and Skoog (LS) medium with or without the addition of 5 mM meta-fluoro-tyrosine (MFT). The alterations in peroxidase activity and relative protein levels were correlated with the growth inhibition by MFT, particularly for the cationic isozyme. A further direct link between growth and the peroxidase has been established by the addition of either antibodies or purified isozymes to the culture medium. The enhancement of growth by the antibodies and inhibition by the peroxidase isozymes strongly suggest that peroxidase is directly involved in growth.