XVI CONTENTS 



3.3 Role of Hematin Side Chains in Linkage 239 



3.3.1 Introduction 239 



3.3.2 Synthetic Hemoglobins 239 



3.3.3 Compounds of Globin with Porphyrin and Non- 

 ferrous Metalloporphyrins 240 



3.3.4 Compounds of Porphyrins and Metalloporphyrins 

 with Simple Substances 241 



3.3.5 Methemalbumin (Ferrihemalbumin) 243 



3.3.6 Differential Titration of Globin and Hemoglobin. . . 244 



3.4 Otlier Oxygen-Carrying Pigments 245 



4 Globin and Hemoglobin as Proteins 245 



4.1 Molecular Weight 245 



4.1.1 Hemoglobin 245 



4.1.2 Dissociation of the Hemoglobin Molecule 246 



4.1.3 Myohemoglobin 247 



4.2 Shape of Hemoglobin Molecule and Arrangement of Hemes . . 248 



4.2.1 Shape of the Hemoglobin Molecule 248 



4.2.2 Globin and Cleavage Products of Hemoglobin. . . . 250 



4.2.3 Arrangement of the Hemes 251 



4.3 Denaturation 253 



4.3.1 Definition 253 



4.3.2 Bond Changes on Denaturation 254 



4.3.3 Reversible Denaturation 255 



4.3.3.1 Action of Alkali 255 



4.3.3.2 Action of Acid 256 



4.3.3.3 Other Reagents 257 



4.3.4 Chemical Changes on Denaturation 258 



4.3.5 Reaction between Cephalin and Oxyhemoglobin. . . 258 



4.4 Preparation of Native Globin 258 



5 Hemoglobin Equilibria 260 



5.1 Equilibria in Simple Systems — Interaction between Hemes 260 



5.1.1 Introduction 260 



5.1.2 Hufner's Equation 262 



5.1.3 Hill's Equation 262 



5.1.4 Adair's Equation 263 



5.1.5 Pauling's Equation 265 



5.1.6 Present Status of the Equilibrium Problem 267 



5.1.7 Relation between ?( and a 269 



5.1.8 Hemoglobin-Hemoglobin Equilibrium 270 



5.1.9 Attempt to Discover Intermediates Directly 271 



5.2 Hemoglobin Systems Containing More Than Six Species of 

 Intermediate 271 



5.2.1 Introduction 271 



5.2.2 Haldane Effect 271 



5.2.3 Complex Oxidation-Reduction Systems 274 



5.2.4 Variation of Oxygen Affinity and Oxidation-Reduc- 

 tion Potential with pH 275 



6 Kinetics of Hemoglobin Reactions 278 



6.1 Methods 278 



6.2 Kinetics of Individual Reactions with Carbon Monoxide and 

 Oxygen 279 



6.2.1 HbOo^Hb + Oj 279 



