Effect of monovalent cations on the malic enzyme from the extreme halophile, Halobacterium cutirubrum

The malic enzyme from Halobacterium cutirubrum requires monovalent cations for both activation and stabilization. NaCl, the best stabilizer, is ineffective as activator; NH(4)Cl, the best activator, is a poor stabilizer. These results support the idea that the roles of salts in both processes are different.