Binding to DNA protects alpha/beta-type, small, acid-soluble spore proteins of Bacillus and Clostridium species against digestion by their specific protease as well as by other proteases.

Binding of alpha/beta-type, small, acid-soluble proteins from Bacillus subtilis and Clostridium bifermentans to DNA protected these proteins against cleavage by their specific protease (GPR) as well as by trypsin and chymotrypsin. These data suggest that alpha/beta-type, small, acid-soluble protein binding to DNA (i) may result in a structural change in these proteins, giving a more compact protein structure, and (ii) may be important in slowing the degradation of these proteins by GPR, in particular during sporulation.