The Cfx genes in <taxon tax_id="106590">Ralstonia eutropha</taxon> (Alcaligenes eutrophus) encode a number of Calvin cycle enzymes. The observed sizes of twoof the gene products, CfxX and CfxY, are 35 kDa and 27 kDa respectively [<cite idref="PUB00002204"/>]. No functions couldbe assigned to CfxX and CfxY, but CfxQ is required for the expression of rubisco. These proteins show ahigh degree of similarity to the <taxon tax_id="1423">Bacillus subtilis</taxon> stage V sporulation protein K [<cite idref="PUB00003809"/>].