Freeze-Etching of Bacteria

摘要: Publisher Summary The first electron micrographs of bacterial cells were published about 20 years ago. These early studies suggested the presence definite intracellular structures. Sectioning techniques, originally developed for eucaryotic cells, gradually modified so that thin sections bacteria could be obtained. procaryotic revealed an unsuspected level complexity. While microscopes have advanced technically, preparative techniques biological material not kept pace. newest models a potential resolution 0.2-0.3 nm but less refined denied biologists use this degree sophistication. Some difficulties encountered in preparation microscope examination are intrinsic and unavoidable. Live cannot examined section process fixation dehydration frequently alters or even extracts cellular components, leaving preservation structural integrity open to question. About 10 ago, new technique permitting replication freeze-fractured live specimens was developed. This method allowed internal morphology had neither been dried nor chemically fixed seen, thereby eliminating minimizing many artifacts typically introduced. chapter discusses freeze-etching; its application cytology, morphology, related fields; possible future development microbiology.