Formed inside the parent vegetative cell. ➢ Endospores are highly durable dehydrated cells, which can survive extreme heat, lack of water, freezing and exposure to many toxic chemicals and radiation. ➢ Endospores also called as “resting cells”.

1. BACTERIAL
ENDOSPORES
Dr. Jagadisha T.V., M.Sc., PGDGT., PhD
Assistant Professor
Department of Life Sciences (Genetics)
Kristu Jayanti College (Autonomous)
(Reaccredited A++ Grade by NAAC with CGPA 3.78/4)
K. Narayanapura, Kothanur Post, Bangalore - 560 077
Karnataka, INDIA.
Ph.-No: 8892698143/9449442521,

2. Spores
Endospore;
➢ Formed inside the parent vegetative cell.
➢ Endospores are highly durable dehydrated cells,
which can survive extreme heat, lack of water,
freezing and exposure to many toxic chemicals
and radiation.
➢ Endospores also called as “resting cells”.
o Exospore ;
➢ Formed outside the vegetative cell by budding at one end
of the cell.
➢ The Exospore do not contain dipicolinic acid.
➢ They can resist desiccation and
heat

3. BACTERIAL
ENDOSPORES
 Endospores are the resisting structures formed
by bacteria for survival during adverse
environmental condition.
 Endospores differ significantly from the
vegetative and normal functioning of cells.
 Endospores provide resistance against
⚫ Heat
⚫ Drying
⚫ Low nutrient conditions
⚫ Radiation
⚫ Osmotic pressure
⚫ Various chemical disinfectants

4. SPORE PROTEINS
 Dipicolinic acid
 Located in the core
 Calcium – Dipicolinic acid complexes reduces water
available and helps to dehydrate spores.
 Interculates into the DNA and stabilizes it to heat
denaturation.
 Small Acid Soluble Proteins (SASPs)
 Bind to the DNA in the core and protect it from
damage.
 Function as a carbon and energy source when
forming vegetative cells to spore cells.

5. THE SHAPE OF THE SPORE IS AN
IDENTIFYING CHARACTERISTIC
 Swelled vs. Not swelled
spore
Bacterial cell spore
Bacterial cell

6. LOCATION OF THE SPORES
 Central, Sub-Terminal, and Terminal spores

8. ENDOSPORE STAINING

10. • Endospore formation :
When certain essential elements like
carbon ,nitrogen and phosphorus are limited
or completely depleted or when water is
unavailable certain gram (+) bacilli from
specialized resting cells called endospores.
These endospores are highly durable
dehydrated cells which can survive extreme
heat, lake of water, freezing and exposure to
many toxic chemicals and radiation . The
genera of bacteria giving rise to endospore