. The cytology and life-history of bacteria. Bacteria. CYTOLOGY LIFE-HISTORY B A C T K RI A H: CELL IV ALL STAINS (S, 9, i6, 18, 20, 26, 27, 2S, 37, 3S, 39, 45, 53, 56, 66) Bacteria arc enclosed in a rigid cell wall which normally resists staining. It may be rendered visible by mordanting in tannic acid, phosphomolybdic acid or cationic detergents. These agents serve the dual purpose of mordanting the cell wall and so altering the protein material ot the cell that it is rendered unstainable and does not obscure the details ot the transverse septa, where these occur. Tannic acid also forms a st
. The cytology and life-history of bacteria. Bacteria. CYTOLOGY LIFE-HISTORY B A C T K RI A H: CELL IV ALL STAINS (S, 9, i6, 18, 20, 26, 27, 2S, 37, 3S, 39, 45, 53, 56, 66) Bacteria arc enclosed in a rigid cell wall which normally resists staining. It may be rendered visible by mordanting in tannic acid, phosphomolybdic acid or cationic detergents. These agents serve the dual purpose of mordanting the cell wall and so altering the protein material ot the cell that it is rendered unstainable and does not obscure the details ot the transverse septa, where these occur. Tannic acid also forms a stainable complex upon the surface of the cell wall, and it it is stained before the mordanting process is complete, this complex may produce an outline picture of the wall, but fail to show internal details. Using 5-10% tannic acid, the wall can be stained with 0-2°o crystal violet ; with 1% phosphomolybdic acid, i°o methyl green gives the clearest results. The times required for staining and mordanting vary from a few seconds upwards. Fig. 3 THE CYTOLOGICAL STAINING OF COCCI (1) Micrococcus cryophiltis by Hale's method for cell walls. Showing two- or four-celled cocci. (2) A similar group stained by trichloracetic acid and (jiemsa. Such arrange- ments of nuclear material have been misconstrued as mitotic figures by some {Reproduced horn the Jounuil of llaiU-nology) observers. The uncierlying cell membrane is not easily demonstrated. Transverse septa derived from it, containing a large protein component, are stainable by simple, basic dyes or by acid-Giemsa, and are sometimes rendered more obvious by fixation with Bouin's solution or similar agents. Bacteria which have been slightly plasmolysed by such fixatives can be stained by 0-050;^ Victoria blue in such a manner as to demonstrate the cell wall and cell membrane Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appea
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Keywords: ., bookcentury1900, bookcollectionbiodiversity, booksubjectbacteria
