Germin-like proteins

Monocupins include bacterial carbohydrate isomerases and epimerases as well as germins and germin-like proteins (GLPs). So far, Cit s 1 from orange is one of the few members of the germin family, which has been reported to act as an allergen. 

Very recently, a distinct but similar class of oleosin-like proteins also containing the characteristic central hydrophobic domain has been found in the pollen of rapeseed and corresponding genes have been isolated from both rapeseed and Arabidopsis [1]. Like seeds, pollen cells are propagules which carry their own storage compounds which are required to support their metabolism after germination. In the case of rapeseed and Arabidopsis, Ae seeds and pollen each contain oil bodies and are desiccation tolerant [Ij. This established a correlation between desiccation tolerance and the presence of oil body proteins in both gametophytic and sporophytic plant tissues. 

QS, like those of other plants, store proteins in the embryo to provide nutrients for growth and development (Herman and Larkins, 1999). In the food area, proteins stored in seeds are the source of the proteins consumed directly as food by humans (Shewry et al., 1995). Stored proteins provide building blocks for rapid growth upon seed and pollen germination (Herman and Larkins, 1999). Osborne (1924) introduced a classification of plant proteins based on their solubility in a series of solvents, such as albumins in water, and globulins in saline. 

Fig. 155. Staining with cyclic 3, 5 -guanosine monophosphate dependent protein kinase (cGK) antisera of sections of cerebellum of rat fetuses of embryonic day E17, E19 and a neonate (PO) cut in the frontal plane. A,B- E17. Cluster I is composed of a medial sheet (arrow in B) lying against the germinative neuroepithelium. Close to the midline this sheet bends dorsally and reaches the cortex. The central cluster (CC) is located at the center of the hemicerebellum. C. E19. In this section four of the five cGK-positive clusters I-V are present. The labelled fiber-like material, which tails the labelled clusters ( and o) indicates the migration pathways followed by the Purkinje cells of the clusters I and III from the subventricular plate and the central cluster at El7 to their present, superficial position. D. PO rat pup. Fiber bundles linking the clusters I and III with the cerebellar nuclei intersect at the former position of the central cluster. It is suggested that the bundle from cluster III ( ) terminates in the dorsolateral protuberance. In the adult this connection corresponds to the projection of the lateral extension of the A zone of Buisseret-Delmas (1988a, compare Figs. 142 and 144). Bar in A = 100 /tm, in B, C and D = 500 fxm. Wassef and Sotelo (1984).

As indicated in Table XIII, human exposure to soybean isoflavones, measured in DES equivalents, is considerably more likely than exposure to coumestrol in soybeans. Several fold Increases in Isoflavone content during germination is a definite possibility. The Importance of soybean estrogens, particularly in germinated soybeans, in the etiology of deleterious reactions in humans needs more study. Soybean isoflavones and phenolic acids probably account for the antioxidant activity of soybeans, defatted soy flour, protein concentrates, and Isolates (89). 

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