view article
Figure 7
Crystal structure of the mature form of the Class 2 potassium-dependent L-asparaginase from P. vulgaris (PDB entry 4pv2). The mature protein is a heterotetramer built of two α subunits (green and magenta) and two β subunits (cyan and yellow). All Class 2 L-asparaginases possess a stabilization loop with a coordinated Na+ ion (blue sphere). Potassium-dependent enzymes also possess an activation loop that is capable of coordinating a K+ ion (brown sphere).

IUCrJ
Volume 8| Part 4| July 2021| Pages 514-531
ISSN: 2052-2525
https://doi.org/10.1107/S2052252521006011