Biogenesis of methane.

CONTENTS INTRODUCTION 310 THE ROLE OF METHANOGENIC BACTERIA IN INTERSPECIES H, TRANSFER ...... 310 The Methanogenic Bacterial Interaction 312 Low-molecular-weight end products 312 Carbohydrates 315 The Non-Methanogenic Bacterial Interaction 316 METHANOGENESIS FROM ACETATE 317 Acetate Enrichment 318 Methanol Enrichment 318 Benzoate Enrichment 318 PURE CULTURE ISOLATES 319 FINE STRUCTURE STUDIES 320 NUTRIENT REQUIREMENTS 322 BIOCHEMICAL AND ENZYMATIC STUDIES 323 THE ECOLOGY OF METHANOGENESIS 325 Freshwater Sediments ... 326 Distribution of methane and methanogenic bacteria 326 Factors affecting methanogenesis , 328 Fate of methane in freshwater sediments 331