|| Has been suggested to be a proteolytic ATPase. The most conserved regions are in the C-terminus and are similar to the Walker A, B and AAA motifs, see: PubMed=8082182; Wolfe K.H.; "Similarity between putative ATP-binding sites in land plant plastid ORF2280 proteins and the FtsH/CDC48 family of ATPases."; Curr. Genet. 25:379-383(1994). This protein is poorly conserved in sequence and tolerates numerous inserts and deletions. It has suffered major deletions in at least some members of the Passifloraceae, Geraniaceae, Cuscutaceae, Campanulaceae and Poaceae (the grasses); however it seems to be intact in other land plants, see: MEDLINE=94363755; PubMed=8082181; Downie S.R., Katz-Downie D.S., Wolfe K.H., Calie P.J., Palmer J.D.; "Structure and evolution of the largest chloroplast gene (ORF2280): internal plasticity and multiple gene loss during angiosperm evolution."; Curr. Genet. 25:367-378(1994).