Post on 03-Jan-2016
Kingdom EubacteriaKingdom
Archaebacteria
Kingdoms Eubacteria/Archaebacteria Eubacteria contain bacteria cells with
cell walls made of peptidoglycan
Archaebacteria contain bacteria cells with no cell walls.
Bacteria can be found anywhere! Many of them live in places where no other forms of life can survive! (Archaebacteria)
What we already know….
Characteristics: Prokaryotic no membrane-bound
organelles
Single-celled or colonial All of the cells are identical
Heterotrophic or autotrophic
Different types of bacteria… Bacteria cells are
usually one of three different shapes: Rods (bacillus) Spheres (coccus) Spirals (spirillum)
Bacteria
Bacteria can be arranged in several ways:
Single cell2 cells: diploA strand of cells: streptoA cluster of cells: staphylo
Bacteria
When bacteria are found in colonial arrangements, we name them based on their arrangement and their shape.
The first part of the name represents the arrangement. The second part represents the shape.
Examples
EX. Two rod-shaped cells
Diplobacillus
EX. Spherical cells in a linear strand
Streptococcus
Bacteria
Bacterial Cell Structures:
Nucleoid Plasmid Ribosomes Plasma Membrane Cell Wall Flagella Pili
Bacteria
Bacterial DNA is not contained in a nucleus (remember….no membrane-bound organelles!)
Instead, the DNA is tangled up in an area we call the nucleoid.
Bacterial DNA forms loops Known as plasmids
Bacteria
Bacteria cells are classified based on how they react to a certain chemical stain developed by Dr. Gram
Gram-positive. They retain a purple color when
stained with crystal violet.
Bacteria Other bacteria cells have no cell wall and
react differently to the Gram stain
These bacteria are known as Gram negative because they do not stain purple.
How they stain determines what antibiotic is perscribed.
Bacteria Bacteria may achieve motility in
three ways: Using flagella An axial filament (bacteria cell
moves like a corkscrew) Slime
How do bacteria cells reproduce?
Bacteria cells reproduce using binary fission…
Each daughter cell is identical to the parent cell.
Bacterial Conjugationa.k.a Horizontal Gene
Transfer
http://www.learner.org/channel/courses/biology/archive/animations/hires/a_infect1_h.html
Bacterial Conjugation
The connection that is formed between two bacteria cells is known as the conjugation bridge.
The structure that forms the conjugation bridge is called a pili.
The plasmid that gets transferred is known as the F plasmid or the sex plasmid.
Conjugation
Good Bacteria vs. Bad Bacteria There are many bad bacteria in our
environment that can do harm to our bodies.
These bacteria cells are known as pathogenic bacteria
Good Bacteria
Bacteria cells can be easily manipulated and help us produce a variety of products.
For example, we can use bacteria cells to help us produce insulin!
Insulin Production in Bacteria
Insulin Production in Bacteria
Genetic Recombination The gene responsible for insulin production
in humans is removed. The plasmid in the bacteria cell is opened. The human gene is inserted into the
plasmid. The bacteria cell reads the new gene along
with it’s own DNA and becomes an insulin-producing factory!
Insulin is removed from the bacteria cells and given to individuals with diabetes!
Bacteria and Food Production
Bacteria are used in the production of foods such as: Chocolate Sausage Dill Pickles Soy Sauce Olives Dairy Products (Milk,
Cheese, Yogurt)
Bacteria and Vitamins Vitamin B12 is synthesized exclusively
by bacteria through a process called fermentation.
Vitamin B12 is necessary for the synthesis of red blood cells, the maintenance of the nervous system, and growth and development in children.
SAY CHEESE!!
Good Bacteria vs. Bad Bacteria
Bacillus anthracis (causes Anthrax) Commonly occurs in ruminants
Cattle, sheep, goats, etc.
Humans who are exposed to infected animals or a high density of spores (endospore) will become infected.
There are no known cases of people catching anthrax from one another.
Anthrax continued….
Anthrax can infect three different areas: Gastrointestinal
Anthrax (intestine) Pulmonary Anthrax
(lungs) Cutaneous Anthrax
Least fatal; least painful
Escherichia Coli E. Coli live in the lower
intestine of many animals.
However, they can cause several infections when they appear in an area of the body that they are not normally found. Ex. Urinary Tract Infections
Sometimes E. Coli produce a toxin that attacks the body and makes us ill. Ex. Food Poisoning
Streptococcus pharyngitis
These bacteria attack the pharynx.
These bacteria are spread through direct contact(water dropletsfrom sneezing andcoughing)
Antibiotics/Immunity
How Antibiotics Work
Vaccines and Immunity
Immune System