ON THE PHYSIOLOGICAL-ROLE OF S-METHYLMETHIONINE IN CABBAGE HEADS DURING STORAGE

Changes in S-methylmethionine (SMM) content and in distribution of enz yme activity catalyzing SMM synthesis in different parts of cabbage (B rassica oleracea L. var. capitata) heads during their storage were stu died. The activity of the enzyme catalyzing die SMM synthesis was die highest in the outward and middle leaves, whereas the highest SMM cont ent was observed in the apical bud area. The considerable increase in SMM content in the apical bud area coincided in time with the plant tr ansition from die vegetative to generative stage. The activity of S-me thylmediionine : homocysteine S-methyltransferase was found in the sec ond-year shoots. According to this data, we suggest that SMM synthesis proceeds in the outward parts of the head and that SMM then transloca tes into the apical bud area to participate in methionine resynthesis from homocysteine, thus providing the rapidly growing tissues with fre e methionine.