1. BACTERIA

2. Spherical
Rod-shaped
Spiral

3. Structure

4. Cell-Surface
1. Cell wall is made of peptidoglycan.
2. In Gram strain...

6. The lipid portions of the lipopolysaccharides in the walls of many gram-negative bacteria are toxic,causing fever or shock. Ther outer membrane of a gram-negative bacteria helps protect it from the body′s defenses. Some capsule protect against dehydration,and some prokaryotes from attacks by their host′s immune system. Frimbriae(singular,fimbria), pili(singular,pilus) and flagellum

7. DNA
Because lack a membran-bounded nucleus,the chromosome is located in the nucleoid.
In addition to its single chromosome,a typical prokaryotic cell have much smaller rings of independently replicating DNA molecules called plasmids.

8. Endospores
When environments lack essential nutrient.
Bacillus anthracis

9. Conjugation

10. Bacteria have both beneficial and harmful impacts on humans
Bacteria have both beneficial and harmful impacts on humans. Benefit : environment medical mutualistic Harm : diease

11. Actinobacteria (放線菌)---one example of bacteria
(1) Actinobacteria are a group of Gram-positive bacteria
(2) Actinobacteria have high guanine and cytosine content
in their DNA
(3) terrestrial or aquatic
(4) Actinobacteria are one of the dominant phyla of
Bacteria

12. Characteristics of Actinobacteria
(1) Include some of the most common soil life, freshwater
life, and marine life
(2) Decomposition of organic materials, such as cellulose
and chitin
(3) Supply of nutrients an important part of humus
formation

13. Actinobacteria --- bacteria or fungi??
fungi characteristics : 1. Some Actinobacteria form branching filaments,resemble
the mycelia (絲狀體) of fungi
2. Some Actinobacteria species produce external spores.
---> Originally classified under the older name
Actinomycetes
bacteria characteristics :
1. Actinobacteria have no nuclear envelope
2. Cell wall is made of peptidoglycan

14. some of Actinobacteria can cause diseases
(1) Mycobacterium Mycobacterium tuberculosis cause
Tuberculosis(肺結核)
Mycobacterium leprae cause Leprosy(痲瘋病)

15. some of Actinobacteria can cause diseases
(2) Corynebacterium diphtheriae cause Diphtheria (白喉)

16. some of Actinobacteria can cause diseases
(3) Nocardia can cause Nocardiosis(諾卡氏菌病)

17. Some of Actinobacteria can produce antibiotics ---
There are more than 2000 kinds of antibiotics in the
world,and almost 56% produce by Actinobacteria
In 1942 Selman Waksman discovered that the soil bacteria
he was studying made actinomycin(放線菌素)
--->Streptomyces (鏈黴菌屬)
(1) Streptomycin(鏈黴素) : Streptomyces griseus

18. some of Actinobacteria can cause diseases
(2) Oxytetracycline(土黴素) : Streptomyces rimosus
(3) Gentamicin(慶大黴素) : Micromonospora(微單孢 菌屬)