鸡蛋果幼叶PK_(c)的K_(m)(PEP)为0.037mmol/L, K_(m)(ADP)为0.05mmol/L, 与成长叶相同。幼叶PK_(c)的效应物与成长叶的有较大差异, 草酸和Ca~(2+)对幼叶PK_(c)抑制机制与成长叶相同, 但亲和力不同, 可能反映了酶的非活性部位具有不同的构象。图7表2参12
关键词： 鸡蛋果幼叶; 细胞质丙酮酸激酶; 代谢物; Ca~(2＋)
Regulatory properties of cytosolic pyruvate kinase from young leaves of Passiflora edulis
Guo Zhenfei, Li Mingqi
Laboratory of Photosynthesis Research, South China Agricultural University. Guangzhou,Guangdong
The PK_(c)from young leaves of P. edulis exhibited a Michaelis-Menten type kinetics for PEP and ADP, K_(m)(PEP)=0.037 mmol/L, K_(m)(ADP)=0.05mmol/L, which was the same as that from mature leaves (Fig. 1). Some metabolites, such as Asp, Asn, nalate, which activated PK_(c)from mature leaves, had no effect on PK_(c)from young leaves; #alpha#-ketoglutarate, which activated PK_(c) from mature leaves, had inhibitory effect on PK_(c)from young leaves. Fumarate, which did not affect PK_(c)activity in mature leaves, inhibited PK_(c)in young leaves. ATP slightly inhibited PK_(c)in young leaves and had no effect at its physiological concentration, whereas it inhibited PK_(c)potently in mature leaves.
Key words: Young leaf Passiflora edulis;Cytosolic pyruvate kinase;Metabolites;Ca~(2+)
郭振飞, 李明启. 鸡蛋果幼叶细胞质两酮酸激酶的调节特性[J]. 生理学报 1994; 46 (3): .
Guo Zhenfei, Li Mingqi. Regulatory properties of cytosolic pyruvate kinase from young leaves of Passiflora edulis. Acta Physiol Sin 1994; 46 (3): (in Chinese with English abstract).