A probable inner membrane protein. Has been shown not to be a toxin, no effects on growth are seen in LB or minimal medium up to 6 or 21 hours (respectively) after induction of expression (PubMed:23657679). Interacts with cytoskeletal proteins FtsZ and MreB; inhibits FtsZ GTP-dependent polymerization as well as MreB ATP-dependent polymerization (PubMed:22239607). Restores production of prodigiosin antibiotic (Pig) in Serratia strains with deletions of sdhE-ygfX; overexpression of this protein and CptB also restores Pig production to a slightly lesser extent in Serratia (PubMed:22474332). Interacts with MreB and FtsZ; interaction with the latter requires FtsZ residues 33-49 (PubMed:22239607). Was originally thought to be the toxic component of a type II toxin-antitoxin (TA) system; overexpression was shown to lead to growth arrest after 5 hours, with initial elongation of cells, followed by swelling (PubMed:22239607). The toxic effects were abrogated by coexpression with antitoxin CptB (now sdhE) (PubMed:22239607). However subsequent studies have been unable to show the toxic effect upon overexpression, nor is the Serratia ortholog a toxin (PubMed:23657679).