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. 1974 Aug;28(2):312–316. doi: 10.1128/am.28.2.312-316.1974

Critical-Point Drying: Rapid Method for the Determination of Bacterial Extracellular Polymer and Surface Structures

Gerald D Cagle 1
PMCID: PMC186707  PMID: 4136617

Abstract

The relative amount of extracellular polymer which remains about Azotobacter vinelandii, Zoogloea ramigera, Klebsiella pneumoniae, and Diplococcus pneumoniae after critical-point drying was studied by electron microscopy. The results obtained with this technique are compared to those obtained with methods that illustrate extracellular polymer, such as freeze-etching and ruthenium red staining. Comparative results indicate critical-point drying to be a rapid, reliable method for the determination of capsule-like polymer surrounding bacterial cells. In addition, critical-point drying can be used to observe morphogenetic changes, such as vesicle production.

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Selected References

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