Crystal structure of an aspartate aminotransferase Lpg0070 from Legionella pneumophila

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 alpha-amino between aspartate and alpha-ketoglutarate to form glutamate and oxaloacetate. Here, we report the crystal structure of Lpg0070 at the resolution of 2.14 angstrom and 1.7 angstrom, 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.

Automated summary

In this study, the crystal structure of Legionella pneumophila aspartate aminotransferase (Lpg0070) and its functionality were investigated. The results revealed the crucial role of the N-terminal arm in enzyme activity.