STAINING BACTERIAL CAPSULES

The demonstration of bacterial capsules by Fontana's staining procedure.

It has been discovered that, in addition to bacterial cells being stained a very dark brown or black color by Fontana's procedure, bacterial capsules are differentially stained a light brown color. Fontana (Dermatol. Wochschr., 55, 1003, 1912 and Pathologica, Genova, 4, 582, 1912) described a method for staining Treponema pallidum and other spirochetes by the AgNO3NH40H method. A similar proced...

The staining of bacterial capsules and slime with ferric compounds.

In 1946 Hale described a method for demonstrating acid mucopolysaccharides in sections based on the affinity of these compounds for colloidal iron oxide in acid solution. The combined iron was demonstrated by conversion to prussian blue. It has been found that bacterial capsules and slime are very well stained by Hale's method. This is possibly due to their content of acid mucopolysaccharides, ...

Staining bacterial flagella easily.

A wet-mount technique for staining bacterial flagella is highly successful when a stable stain and regular slides and cover slips are used. Although not producing a permanent mount, the technique is simple for routine use when the number and arrangement of flagella are critical in identifying species of motile bacteria.

Staining bacterial polysaccharides.

A Simple Method for Staining the Capsules of Bacteria.

The possession of mucinous envelopes by certain bacteria, apart from their purely morphological interest, has a great value in the identification of such organisms and many methods have been devised for their demonstration. The number of such methods however argues against any one being completely satisfactory. The introduction of a new technique into this already overcrowded field can be justi...