Re: About bovine catalase and NADP?

Hi,

Bovine catalase does not absolutely require NADP for function. It is 
thought by some researchers that the role of NADP may be to help protect 
the enzyme against its very reactive substrate (H2O2), it is also known 
that the NADPH site can be involved in binding of cognate mRNA which 
regulates the level of catalase protein synthesis via sequestration of the 
messenger - this is a regulatory mechanism designed to sense oxidative 
state of the system in general.

There are many types of catalases and peroxidases in Nature, some with 
prosthetic factors like NADP and some without. It is not really easy to 
assign differences in catalytic activity to something as complex as 
nucleotide binding, especially when the system is designed for intricate 
and delicate control of complicated intracellular processes. If I were 
you, I would read further on the relationship between catalase and 
metabolic processes (including alcohol metabolism!) and try to summarize 
the complex regulatory mechanism involved in catlase mRNA complexation.

Good luck, feel free to ask further questions.

A.G.E.

Putnam,C.D., Arvai,A.S., Bourne,Y., Tainer,J.A., 
Active and inhibited human catalase structures: ligand and NADPH binding 
and catalytic mechanism. 
(2000) J. Mol. Biol. 296:295-309

 Eventoff, William. (1976) Crystalline Bovine Liver Catalase. J. Mol. 
Biol. 103, 799-801. 

Fita, et al. (1985) The active center of catalase. J. Mol. Biol. 185, 21-
37. 

Fita, et al. (1986) The refined structure of beef liver catalase. Acta 
Cryst. B42, 497-515. 

Jouve, et al. (1991) Crystallization and crystal packing of Proteus 
mirabilis PR catalase. J. Mol. Biol. 221, 1075-77. 

Mathur, et al. (1981) Structure of beef liver catalase. J. Mol. Biol. 152, 
465-99. 

Melik-Adamyan, et al. (1986) Comparison of beef liver and Penicillium 
vitale catalases. J. Mol. Biol. 188, 63-72. 

Reid, et al. (1981) Structure and heme environment of beef liver catalase 
at 2.5 A resolution. Proc. Natl. Acad. Sci. USA 78, 4767-71. 

Vainshtein, et al. (1981) Three-dimensional structure of the enzyme 
catalase. Nature 293, 411-12. 

Vainshtein, et al. (1986) Three-dimensional structure of catalase from 
Penicillium vitale at 2.0 A resolution. J. Mol. Biol. 188, 49-61.