Abstract：
Legionella pneumophila aspartate aminotransferase (Lpg0070) is a member of the transaminase and belongs to the pyridoxal 5\'-phosphate (PLP)-dependent superfamily. It is responsible for the transfer of α-amino between aspartate and α-ketoglutarate to form glutamate and oxaloacetate. Here, we report the crystal structure of Lpg0070 at the resolution of 2.14 Å and 1.7 Å, in apo-form and PLP-bound, respectively. Our structural analysis revealed the specific residues involved in the PLP binding and free form against PLP-bound supported conformational changes before substrate recognition. In vitro enzyme activity proves that the absence of the N-terminal arm reduces the enzyme activity of Lpg0070. These data provide further evidence to support the N-terminal arm plays a crucial role in catalytic activity.
摘要：
嗜肺军团菌天冬氨酸转氨酶（Lpg0070）是转氨酶的成员，属于吡哆醛5'-磷酸（PLP）依赖性超家族。它负责天冬氨酸和α-酮戊二酸之间的α-氨基转移以形成谷氨酸和草酰乙酸。这里,我们报告了Lpg0070的晶体结构，分辨率为2.14和1.7，在apo形式和PLP绑定中，分别。我们的结构分析揭示了与PLP结合有关的特定残基，以及在底物识别之前针对PLP结合的支持的构象变化的游离形式。体外酶活性证明N-末端臂的缺失降低了Lpg0070的酶活性。这些数据提供了进一步的证据来支持N-末端臂在催化活性中起关键作用。
