CONTENTS 



OXIDASES, PEROXIDASES, AND CATALASE 



By Kurt G. Stern, Yale University School of Medicine .... 74 



Introduction, 74 On the mechanics of hemin catal- 



The common denominator in hemin yses, 86 



catalyses, 74 Autoxidizable iron compounds, 96 



Enzyme-substrate intermediates, 84 Oxygen transfer in living cells, 99 



NICOTINAMIDE NUCLEOTIDE ENZYMES 



By Fritz Schlenk, School of Medicine, University of Texas 



104 



Historical introduction, 104 

 Codehydrogenase I and II, 104 

 Occurrence, 105 

 Preparation, 106 

 Properties, 108 

 Investigation of the structure of co- 

 dehydrogenase I and II, 109 

 Reversible reduction, 109 

 The "model compounds" of Kar- 

 rer, 111 



Nicotinamide nucleoside, its prepa- 

 ration and properties, 113 



Structure of codehydrogenase I and 

 II, 116 

 Methods of determination, 120 

 Apodehydrogenases dependent on 

 nicotinamide nucleotides, 122 

 Substrate and coenzyme specificity 

 of apodehydrogenases, 123 

 Mode of action of nicotinamide 

 nucleotide enzymes, 125 

 Spectrophotometric methods, 126 

 Biosynthesis of the codehydrogenases 

 I and II, 126 



THE FLAVOPROTEINS 



By T. R. Hogness, University of Chicago 134 



Historical introduction, 134 Comparison of activities, 142 

 The general properties of die known Cytochrome a reductase: test, spec- 

 yellow enzymes, 137 troscopic demonstration, and prop- 

 Dissociation constants, 139 erties, 144 



CYTOCHROMES 



By Elmer Stotz, Harvard University 



Properties of the cytochrome com- 

 ponents, 149 



Cytochrome c: isolation, purifica- 

 tion, structure, and oxidation- 

 reduction potential, 149 

 Cytochrome b, 153 

 Cytochrome a, 154 



Oxidation-reduction potential of the 

 cytochromes in yeast, 154 



Cytochrome oxidase and cytochrome 

 03, 155 



Identity with Warburg's enzyme, 

 157 



Summary of absorption spectra of 

 the cytochromes, 158 

 Copper-containing oxidase, 159 

 Soluble cytochrome c peroxidase, 

 160 



149 



Physiological reduction of the cyto- 

 chromes, 161 



By the succinate system-extra fac- 

 tor, 161 



By flavoprotein (cytochrome re- 

 ductase), 163 



Catalytic relations of the cyto- 

 chromes and oxidase: oxidation of 

 hydroquinone and p-phenylene dia- 

 mine, 164 



Determination and distribution of 

 cytochrome c and cytochrome oxi- 

 dase, 166 



Physiological functioning of the cy- 

 tochrome system, 168 



Possibility of a by-pass of the cyto- 

 chrome system, 169 



