Chelation effects on Azotobacter cells and cysts.

Fatty acids in phospholipids of cells, cysts, and germinating cysts of Azotobacter vinelandii.

Cyclopropane fatty acids constitute 25% of the phospholipid acyl groups in cysts of Azotobacter vinelandii. These are lost by dilution during germination when the synthesis of the fatty acids characteristic of vegetative cell phospholipids commences.

Formation of multiple central bodies in giant cysts of Azotobacter vinelandii.

Cysts of Azotobacter vinelandii produced in chemical salts-agar supplemented with 0.1 to 1.0% yeast extract and 0.3% butanol (L. E. Jackson, M.S. Thesis, Univ. of Texas, Austin, 1961) were two to four times larger than cysts formed on nitrogen-free medium (Fig. 1 and 2). Microscopic studies of "giant" cysts transferred to nitrogenfree agar revealed that, prior to germination, the central body d...

HEAT RESISTANCE IN VEGETATIVE CELLS AND CYSTS OF AZOTOBACTER APPROVED Mad6r Professor Minor Pmessor Director of the Department of Otology Dean 'of the Graduate School HEAT RESISTANCE IN VEGETATIVE CELLS AND CYSTS OF AZOTOBACTER THESIS

Ultrastructure of Azotobacter vinelandii.

Vegetative cells and cysts of Azotobacter vinelandii 12837 were prepared for electron microscopy by several methods assumed to preserve structural details destroyed by techniques previously reported in the literature. Examination of large numbers of cells and cysts by these methods revealed four structural details not reported previously: intine fibrils, intine vesicles, intine membrane, and mi...

Germination of Azotobacter vinelandii cysts: sequence of macromolecular synthesis and nitrogen fixation.

Azotobacter vinelandii cysts undergo conversion to vegetative cells in Burk's nitrogen-free medium utilizing glucose, sucrose, or acetate. In 1% glucose, this overall process was complete in 8 hr and consisted of a germination and an outgrowth phase. Respiration, ribonucleic acid, and protein synthesis began soon after the addition of the germinant, and these processes proceeded at rates charac...