Alföldi L, Raskó I, Kerekes E
J Bacteriol. 1968 Nov;96(5):1512-8. doi: 10.1128/jb.96.5.1512-1518.1968.
The native l-serine deaminase (l-serine hydrolyase, deaminating, EC 4.2.1.13) of Escherichia coli K-12, which seems to be a very labile protein, is rather stable in concentrated solution. Dilution rapidly inactivates it, but in the presence of a saturating concentration of l-serine the molecule is protected from inactivation. It is a very specific enzyme; l-serine is the sole substrate with a K(m) value of 6.60 x 10(-3)m. d-Serine and l-cysteine are competitive inhibitors. Substrate saturation curves of the native enzyme show sigmoid shape, whereas the enzyme liberated from the bacteria in the presence of l-serine exhibits normal Michaelis-Menten kinetics.
大肠杆菌K-12的天然L-丝氨酸脱氨酶（L-丝氨酸水解酶，脱氨基，EC 4.2.1.13）似乎是一种非常不稳定的蛋白质，但在浓缩溶液中相当稳定。快速稀释会使其失活，但在L-丝氨酸饱和浓度存在下，分子可免受失活影响。它是一种非常特异的酶；L-丝氨酸是唯一底物，K(m)值为6.60×10(-3)m。D-丝氨酸和L-半胱氨酸是竞争性抑制剂。天然酶的底物饱和曲线呈S形，而在L-丝氨酸存在下从细菌中释放的酶表现出正常的米氏动力学。
