The Three-Domain System · . Gram positive cell wall Membrane protein. Gram negative cell wall 25. SIMPLE STAINING:- METHYLENE BLUE staining. IMPART SAME COLOUR TO ALL BACTERIA. USED

The Three-Domain System

Figure 10.1

Prokaryotes

Figure 10.6

Morphology & Physiology

of Bacteria

fimbriaglycocalyx

pilus

flagellum

Cell wall

Cell membrane

ribosome

Outer membrane

Actin cytoskeleton

Bacterial chromosome or nucleoid

Inclusion/ granule

Bacterial cell

Flagellum

DEMONSTRATION OF FLAGELLA

DARK GROUND ILLUMINATION ELECTRON MICROSCOPY SPECIALSTAINING MORDANTING

Bacterial flagella - Electron microscopy

Peritrichous

Polar

Bacterial flagella - Scanning Electron Microscopy

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Gram positive cell wall

Membrane protein

Gram negative cell wall

25

SIMPLE STAINING:-

METHYLENE BLUE staining IMPART SAME COLOUR TO ALL BACTERIA

USED TO KNOW THE ARRANGEMENT

NEGATIVE STAINING

INDIA INK / NIGROSIN

TO DEMONSTRATE

BACTERIAL CAPSULE, FUNGAL CAPSULE

Gram staining

GRAM STAINING

GRAM POSITIVE BACTERIA - VIOLET STAPHYLOCOCCUS STREPTOCOCCUS

GRAM NEGATIVE BACTERIA - PINK E.COLI KLEBSIELLA

ACID FAST STAINING ZEIHL-NEELSON METHOD

PINK COLOR BACILLI

TUBERCLE BACILLI

LEPRA BACILLI BACTERIAL SPORES, CRYPTOSPORIDIUM

Spores - types

Endospore formation

Vegetative cell

Vegetative cell becomessporangium in preparation forSporulation

Sporangium

Sporangium withprospore

Sporangium with prospore

Mature endospore

Free spore

Germination

1.Germinal groove

2.Outer cortical layer

3.Cortex

4.Inner spore coat

6.Outer spore coat

Bacterial spore

Cocci

Cocci - arrangement

Bacilli

Spirilla – rigid spiral forms

Spirochetes- flexuous spiral forms

Bacterial growth BACTERIA ON SOLID

MEDIA COLONIES

BACTERIA ON LIQUID MEDIA TURBIDITY

BACTERIAL GROWTH CURVE

Lag phase - with no increase in number ( adaptation of new surrounding)

Log phase - phase of division

Stationary phase - division stops due to depletion of nutrients.Phase of decline - due to cell death.

A = lag phase,B = acceleration phase,C = log (exponential) phase

D = stationary phase, E = death phase.

BACTERIAL METABOLISM

OXIDATION FERMENTATION

Fermentation ( Anaerobic Condition)

The Three-Domain System

Figure 10.1

Prokaryotes

Figure 10.6