Download Endospore Staining First Semester 2014-2015

Faculty of Medicine and Health Sciences
Microbiology Lab 7 (IMAGES)
Endospore Staining
First Semester 2014-2015
Prepared by : Dr Alaeddin Abuzant, PhD Microbiology and Immunology
E-mail: [email protected]
Fungi from spore. However, spore formation in fungi is used for reproduction. In contrast,
bacterial endospores are formed for survival.
Bacterial Endospores
Fungal Spores
The Sporulation Process
Bacteria can form endospores in approximately 6 to 8 hours after being exposed to
adverse conditions
The Sporulation Process
Endospore Germination and Emergence
of the Vegetative Bacterial Cell
When endospores are exposed to favorable conditions, they germinate into a vegetative
(metabolically active) cells within 90 minutes.
The Structure of the Bacterial Endospore:
Bacillus anthracis Cental Endospores
Bacillus subtilis Subterminal Endospores
Clostrdium tetani Terminal Endospores
Expected Results:
The endospores within mother cells or the released spores will be stained green with
malachite green
Endospore-forming bacterial cells will show a green endospore within the mother cells
surrounded by a red-stained cytoplasm (the color of the counter stain, Safranin).
In the smear of endospore-forming bacterium, it is possible to see vegetative bacterial
cells that did not form the endospores yet, these will appear red.
In the smear of non-spore-forming bacterium, you will see only red bacterial cells.
Nothing will be stained green, since we have no spores