Light-microscopic investigation of the microorganisms in the hypolimnion of many lakes, shows the presence of a highly diverse population of bacteria. Here, most of the recognizable forms have never been cultured and many of them have not even been described morphologically. Among these bacteria are rod-shaped organisms that are bent in an arc by asymmetric, polar cell growth and that frequently assume the shape of a pretzel. Cell division in the center and separation result in two arcs that face each other. Additional cell divisions and the presence of masses of polymer lead to even numbers of arcs facing each other in a symmetric, mirror-image way (Fig. 1).
KeywordsPhotosynthetic Bacterium Sulfide Oxidation Form Cell Plate Polar Cell Growth Polymer Capsule
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