1. Kingdom Monera – Bacteria Characteristics and Diversity

2. Bacteria were first identified in 1677 by Antonie van Leeuwenhook after he developed a primitive version of the compound microscope.
He originally called all single celled organisms he had discovered “animalcules” and they were later separated into groups, one of which included bacteria.

3. A few bacteria that cause human disease
Salmonella bacteria (red) : causes Salmonella poisoning
E.Coli bacteria
Helicobacter pylori: can cause ulcers, stomach cancer…
Tetanus bacteria

4. Bacterial shape influence the ability of the bacteria
Bacterial Shapes
Bacterial shape influence the ability of the bacteria
-to attach to surfaces
-acquire nutrients
-move through liquids
-escape predators

5. Bacteria are found in three distinct shapes
Rod shaped : Bacilli
ex. Anthrax (Bacillus anthraxis) & Tetanus (Clostridium tetani)

6. 2. Spherical shaped
Can be found as single cocci, pairs (diploid), chains, or clumps
Single cocci

7. 2. Spherical shaped Can be found as single cocci, chains, or clumps
Diploids – pairs of spherical shaped bacteria
ex. Neisseria (can cause gonorrhea, bacterial meningitis & septicemia)
Bacterial meningitis
Neisseria : gonorrhea

8. 2. Spherical shaped Chains of spherical shaped bacteria
ex. Streptococcus ( cause a variety of human disease including meningitis, flesh eating disease, and bacterial pneumonia)

9. 2. Spherical shaped Chains of spherical shaped bacteria
ex. Streptococcus ( cause a variety of human disease including meningitis, flesh eating disease, and bacterial pneumonia)

10. 2. Spherical shaped Clusters of spherical shaped bacteria
ex. Staphylococcus aureous (can cause a variety of human infections including skin infections, Toxic Shock Syndrome, meningitis….)

11. 3. Spiral shaped Actually are a form of rod shaped bacteria
Leptospirillum

13. Bacterial Structure
Example: bacillus structure

14. Internal cell structures
Surrounded by a cell membrane
Acts as a barrier and holds in proteins and other parts of the cytoplasm
Allows for transport of energy and materials across it via a concentration gradient
Single ring of genetic material (chromosome) encased in a nucleoid

15. External cell structures
Cell Wall
Composed of peptidoglycan (as opposed to cellulose in plant cells)
Two types
Gram positive – have a thick cell wall
Gram negative – have a thin cell wall and most bacteria fall into this category
Important in antibiotic use as antibiotics affect the ability to produce a cell wall
Flagella
Used for motility and are driven by energy
Can be found alone, at each end, in clusters at the poles or all over the cell
Pili (sing. Pilus)
Used for transferring genetic material between cells
Fimbriae
Fine filaments of protein that aid in the attachment to other cells

16. Specialized External Structure: Endospore:
-adaptation to survival during unfavorable conditions
-form dormant or resting cells
-resistant to severe physical and chemical stresses
-simply constructed of a central core of DNA that is surrounded by an impenetrable layer
- can remain viable for millions of years
-are capable of causing some serious diseases:
ex. Anthrax (Bacillus anthraxis) & Tetanus (Clostridium tetani)

17. Bacteria have recently been classified by the environment that they live in
Archaebacteria – live in an environment
without oxygen
2. Eubacteria – live in an environment with
oxygen
(archae= old)
(eu= true)

18. Bacteria can also be grouped according to their type of respiration
Obligate aerobes – must have oxygen to survive
Obligate anaerobes – can only grow in the absence of oxygen
Facultative anaerobes – prefer environments with oxygen but can live in environments without oxygen

19. Nutrition: How do bacteria get the food (carbon) and energy they need to survive?
Some are autotrophs (collect their own energy)
Photosynthetic - use of light for energy
Chemosynthetic – use of chemical substances for energy
Some are heterotrophs (obtain food from other sources)
Saprophytic (obtain raw materials from dead and decomposing matter)
Parasitic
Symbiotic / mutualistic (ex. Bacteria in the human colon)
Some are chemotrophs (perform fermentation)

20. Modes of Bacterial disease transmission
Direct contact
Airborne droplets
Bacterial toxins in food (ingestion)
Fecal contamination of food
Water
Vector bites (ex. Mosquito)