<p>Proteins in this entry include the stage V sporulation protein K (SpoVK), a close homologue of the Rubisco expression protein CbbX (<db_xref db="INTERPRO" dbkey="IPR000470"/>), and are members of an ATPase family associated with various cellular activities. These proteins are strictly limited to bacterial endospore-forming species, but are not found universally among members of this group; they are missing from the Clostridium species.</p>