The ninaE promoter drives expression of a bicistronic transcript that encodes two open reading frames (ORFs) separated by a 2A linker (this results in separate translation of each protein). The first ORF encodes mCherry (internal control). The second ORF encodes a proteasome activity reporter that consists of GFP tagged with a degradation signal (Tag:degron(CL1)) plus Tag:FLAG.