Protein deamidases from germinating seeds

Abstract

Enzymes catalyzing the deamidation of seed storage proteins were found in germinating seeds of kidney beans (Phaseolus vulgaris L. cv. Moldavian) and squash (Cucurbita pepo L. cv. Mozoleevskaya). They were partially purified and characterized. The properties of these enzymes closely resemble those of the protein deamidase in germinating wheat grains. The detection of similar protein deamidases in germinating seeds of plants belonging to phytogenetically unrelated species indicates that protein deamidases are of considerable physiological significance.

Protein‐glutaminase from Chryseobacterium proteolyticum, an enzyme that deamidates glutaminyl residues in proteins

“…Protein‐deamidating enzymes, described as protein deamidase, in germinating plant seeds were reported as enzymes possibly involved in the seed germination process [15,16]. The wheat grain enzyme was partially purified and characterized [15].…”

“…Deamidation of proteins preceding their proteolytic degradation was observed in germinating seeds [12,13] and increased susceptibilities of deamidated proteins to proteases have been inferred in plant storage proteins [13,14]. Vaintraub and colleagues reported the possible involvement of enzymatic action in this process and the partial purification of the protein‐deamidating enzymes from germinating wheat grain [15], kidney beans and squash [16].…”