YisK possesses oxaloacetate decarboxylase activity and exhibits Mbl-dependent localization.

YisK is an uncharacterized protein in previously shown to interact genetically with the elongasome protein Mbl. YisK overexpression leads to cell widening and lysis, phenotypes that are dependent on and suppressed by mutations. In the present work, we characterize YisK's localization, structure, and enzymatic activity.