Functionality of mepK variants and orthologs. (A) ∆mepS ∆mepK strain carrying either vector (Ptrc), pPK17 (Ptrc::mepK), pPK19 (Ptrc::mepKH133A), pPK20 (Ptrc::mepKD140A), or pPK21 (Ptrc::mepKH173A) was grown in LB, and viability was tested on NA plates with IPTG (0.5 mM) at 30 °C. (B) ∆mepS ∆mepK strain carrying vector (Ptrc), pPK17 (Ptrc::mepK-HisE.
coli;Ec), pPK23 (Ptrc::mepK-HisC.
crescentus;Cc), or pPK25 (Ptrc::mepK-HisK. pneumoniae;Kp) was grown in LB and processed as described above.