Encystment and germination in Azotobacter vinelandii.

INTRODUCTION .......................................................... 516 Speciation ............................................................... 516 Rationale for Studying Encystment. ......... ............................ 516 LIFE CYCLE OF A. VINELANDII .......... .............................. 517 The Organism and Its Culture ............ ................................ 517 Ultrastructural Changes upon Encystment ........ ........................ 518 Cyst Properties .................. ........................................ 521 Fractionation of Cysts .................. .................................. 521 INDUCTION OF ENCYSTMENT ........... ............................... 523 Chemical Inducers ....................................................... 523 Catabolism and Respiration ............. ................................. 524 Shifts and Metabolism .................. .................................. 525 Macromolecular Synthesis .............. .................................. 526 GERMINATION............................................................ 528 GENETICS OF A. VINELANDII ........... ............................... 529 COMPARATIVE ASPECTS OF CYST, ENDOSPORE, AND MYXOSPORE FORMATION .................. ........................................ 531 Spore Morphology and Induction ........... .............................. 531 Endospores ..................... ....................................... 531 Myxospores ..................... ....................................... 532 Synthetic and Metabolic Patterns in Morphogenesis ...... ................. 532 Germination ............................................................. 533 CONCLUSION ............................................................. 533 LITERATURE CITED ..................................................... 533