Conserved chloroplast open-reading frame ycf54 is required for activity of the magnesium protoporphyrin monomethylester oxidative cyclase in synechocystis PCC 6803 - Hollingshead, S; Kopecna, J; Jackson, P; Canniffe, D; Davison, P; Dickman, M; Sobotka, R; Hunter, C (Journal of Biological Chemistry, 2012)