FIG. 3.

Stained AWI collections. (A) Molecular Probes Live/Dead BacLight viability kit staining indicates that most of the bacteria in this freshly collected AWI specimen are intact (green), while some cells are moribund (red). (B) A routine Gram stain does not require the use of a naked flame for heat fixation. Results are easily distinguishable with a ×40 objective. Some algal cells are visible as large red circles. (C and D) Organisms collected from an environmental site viewed with fluorescence optics (C) and with DIC optics (D). The slide was stained with a fluorescein isothiocyanate-conjugated rabbit antiserum.