Cyanobacterial Mn-catalase 'KatB': Molecular link between salinity and oxidative stress resistance.

Catalases are ubiquitous enzymes that detoxify HO in virtually all organisms exposed to oxygen. The filamentous, nitrogen-fixing cyanobacterium, PCC 7120, shows the presence of 2 genes ( and ) that encode Mn-catalases. We have recently shown that pre-treatment of with NaCl causes substantial induction of the KatB protein, which consequently leads to increased oxidative stress resistance in that cyanobacterium.