ABSTRACT
A detailed discussion of the state of knowledge of plant catalases follows, with special emphasis on the maize catalases. A comparison of the similarity of the functional domains of plant and mammalian catalases shows that, although catalytically important regions of the proteins have a high degree of similarity, other domains of the proteins have diverged. The basis for the diversity of catalases in other species continues to be investigated, and indirect evidence suggests that multiple genes for catalase may also exist in other plants. Maize catalases have been extensively characterized, and maize is the only plant system where the genetic basis of the different molecular forms is understood. The role of oxidative stress in effecting specific gene expression is quite intricate when one considers the fact that oxidative insult can affect specific organelles or the entire plant cell or tissue.
