BACTERIAL MORPHOLOGY,
METABOLISM & PHYSIOLOGY
By:
Maria Rosario L. Lacandula,MD,MPH
Department of Microbiology
College of Medicine
Our Lady of Fatima University

The student should be able to:



 describe the typical bacterial cell based on size, shape and groupings.
determine the medical importance of certain structural components in a bacterial cell.
to discuss the appropriate staining procedure to demonstrate bacterial morphology and special structures.
to perform the following staining techniques


Gram staining
Acid-Fast staining




Discuss the growth requirements of bacteria
Differentiate bacteria as to:



 source of carbon source of energy temperature requirement oxygen requirement
Discuss the bacterial growth curve



 lag phase logarithmic phase stationary phase death phase

 Beam of light
 Beam of electron

 Prokaryotes
 No true nucleus
 No organelles
 Divide-binary fission

 Cell envelope
 Cell wall- murein sacculus
 Outer
 Cell membrane-plasma membrane, cytoplasmic membrane
 Cytoplasm
 Nucleiod
 Ribosomes
 Granules/inclusion bodies

 Spores
 plasmids
 Appendages
 Capsule
 pili
 flagella

 Peptidoglycan
 N acetyl glucosamine & N acetyl Muramic acid
 Protect the cell from osmotic changes
 Rigidity
 Multilayered in Gram positive
 Teichoic acid
 Mono to bi layered in Gram negative

 Outer membrane- gram negative only
 2 layers of lipids
 Inner layer-phospholipids
 Outer layer- Lipopolysaccharide

3 regions
 Lipid A

Core polysaccharide

O antigen

 Transmembrane proteins
 Porins
 Integral proteins
 viability

 Lipid bi layer
 Selective permeability
 Site of ATP production
 Viability

 Nucleiod
 Chromosomal DNA
 Plasmids
 Inclusion bodies
 Storage of excess food and energy

Metachromatic granules/ Babes ernst granules
 Much granule
 Spores
 Resist adverse condition
 Ribosome- 70s- 50s & 30s

 Capsule
 Polysaccharide
 Antiphagocytic
 antigenic
 Virulence
 Pili
 Common pili- fimbriae
 Sex pili- conjugation
 antigenic

 Flagella
 Locomotion
 antigenic

 Glucose catabolism
 EMP pathway
 HMP
 Etner duodoroff
 TCA
 ETC

 Fermentation
 Homolactic fermentation
 Heterolactic fermentation
 Mixed acid fermentation


Nutritional requirement
 Carbon

Lithotropic
 Heterotrophic
 Nitrogen
 Inorganic ions
 Growth factors

 Physical Requirements
 Oxygen

Superoxide dismutase
 Catalase
 Redox potential
 Temperature
 Ph
 Osmotic condition

No of viable cell
Lag log
Stationary death time