LIGHT AND ELECTRON-MICROSCOPIC IMMUNOCYTOCHEMICAL LOCALIZATION OF 2 MAJOR PROTEINS IN GARLIC BULB

Garlic is known as a potent spice and a medicine with broad therapeuti c properties ranging from antibacterial to anticancer, antidiabetic, a nd anticoagulant. Two major proteins of 40 KD and 14 KD constituting a pproximately 96% of total garlic proteins have been recently purified at our Institute. This immunocytochemical and ultrastructural study re vealed that the 40 KD protein was localized in the parenchyma sheath c ells (PSC) of garlic bulbs, whereas the 14 KD protein was present in t he cortical cells (CC). Immunogold electron microscopy study indicated that the 40 KD protein was specifically localized in the globular gra nules of the cytoplasmic area of PSC. Each globular granule was amorph ous and homogenous with membrane limiting its outermost layer. The yel lowish color of PSC in freshly cut slices of garlic bulb suggested tha t PSC may have sulfur-containing compounds such as allicin, the primar y contributor of the pungency and medicinal properties of garlic. Ellm an's reagent test quantitatively revealed that there were 17.8 n moles sulfhydryl (SH)/ml of 40 KD garlic protein. Microtubule tubulin in mi totic figures from PHA-stimulated human short-term whole blood culture s reacted strongly with antitubulin antibody but reacted negatively wi th anti-40 KD garlic protein antibodies and therefore was not related to the 40 KD garlic protein immunocytochemically. (C) 1995 Wiley-Liss, Inc.