X CONTENTS 



Lysoii^cnic Hactciid (iiid Pyi>])luiii,i' 122 



Transduction of Bacterial Cw'nrs via Bacteriophage 125 

 Transformation hij D\:\ ISl 

 Mating in Bacteria loi 

 (S. What isaucMic'," 150 



Position Tseudoallelisin 15S 



The Structure of Cenes in Sahnonella 15<S 



The Structure of the CU'ue in B(icterio))ha^e 16S 



.\ (.oncept oj the ilene KiT 



7. ('liroiiiosonic (liiplicafioii and genetic rccomhiiiatioii 1 75 



Coni))arative ( )rii,anization of Genetic Material 1 76 



Chemical Composition of Chromosomes 178 



Electron Microscope Studies of (Uiromosomes IHO 

 Integration of DSA in the Bacterial Cell 1H3 

 D\A and Clircmiosoine Duplication 184 

 Becoml)ination Bevisited 195 



8. Mutation as a chemical process 207 



Mutation and Gene Replication 207 



Incorporation of Unusual Nucleotides and Copy Errors 212 



Point Mutations Versus Grosser Changes in tlie Gene 217 



Mutations Induced by Radiation 219 



The Metabolic Control of Mutation 225 



Directed Mutation 231 



9. Noiichroniosomal genes 234 



Definitions and Criteria 235 



A Review of Cell Structure 244 



Chloroplast Heredity 249 



Mitochondrial Heredity 254 



Nonchromosomal Heredity Involving Mo Known Structures 257 



Infectious agents 262 



Concluding Remarks 268 



10. Some mechanisms of gene action 271 



The Search for Analyzahle Traits 271 

 Genetic Block of Single-Stcj) Reactions 273 

 Qualitatively Altered Enzymes 274 

 Tryptophan Syntlietase 276 

 Hemoglobin 280 

 Some Concepts of Protein Structure 283 



