Specific Detection, Viability Assessment, and Macromolecular Staining of Bacteria for Flow Cytometry

Direct analysis of bacteria from natural environments is problematic. Direct examination of samples by microscopy is an essential technique for bacteriologists, but is prone to error, is time-consuming, and can be tedious. In many situations, the process can be automated using flow cytometry (FCM) (1 ,2 ). FCM can be considered an alternative and complementary technique to microscopy, and it can also extend the range and value of microscopical measurements, allowing quantitative analysis of thousands of bacterial cells, one at a time, every second. Data can thus be obtained on millions of cells, with useful information acquired for individual cells. The option of cell sorting also allows physical separation of specific cells. A detailed discussion of the physical basis of FCM and cell sorting, different instrument configurations, and some applications to environmental bacteriology are given in Chapter 5 .