Biology - ARCHAEBACTERIA & EUBACTERIA
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Transcript of Biology - ARCHAEBACTERIA & EUBACTERIA
Archaebacteria
Methanogens These Archebacteria are anaerobes. They make methane (natural gas) as a waste product. They are found in swamp sediments, sewage, and in buried landfills. In the future, they could be used to produce methane as a byproduct of sewage treatment or landfill operation.
HalophilesThese are salt-loving Archaebacteria that grow in places like the Great Salt Lake of Utah or salt ponds on the edge of San Francisco Bay. Large numbers of certain halophiles can turn these waters a dark pink. Pink halophiles contain a pigment very similar to the rhodopsin in the human retina. They use this visual pigment for a type of photosynthesis that does not produce oxygen. Halophiles are aerobes, however, and perform aerobic respiration.
Extreme halophiles can live in extremely salty environments. Most are photosynthetic autotrophs. The photosynthesizers in this category are purple because instead of using chlorophyll to photosynthesize, they use a similar pigment called bacteriorhodopsin that uses all light except for purple light, making the cells appear purple.
ThermophilesThese are Archaebacteria from hot springs and other high temperature environments. Some can grow above the boiling temperature of water. They are anaerobes, performing anaerobic respiration.
Thermophiles are interesting because they contain genes for heat-stable enzymes that may be of great value in industry and medicine. An example is taq polymerase, the gene for which was isolated from a collection of Thermus aquaticus in a Yellowstone Park hot spring. Taq polymerase is used to make large numbers of copies of DNA sequences in a DNA sample. It is invaluable to medicine, biotechnology, and biological research. Annual sales of taq polymerase are roughly half a billion dollars.
Eubacteria
• Bacteria are prokaryotic and unicellular.
• Bacteria have cell walls, contain peptidoglycan, not cellulose
• Bacteria have circular DNA called plasmids
• Bacteria can be anaerobes or aerobes.
• Bacteria are heterotrophs or autotrophs.
Struktur dasar sel bakteri
Sitoplasma
Ribosom
Nukleoid (DNA)
Membran plasma
Dinding selPeptidoglikan
Membran luar
Kapsul
Bacterial Structures
Characteristics used for Classification:
• RNA sequences and structure• type of nutrition• ability to produce endospores- resistant structures
with cytoplasm and DNA• method of movement• shape, and the way the cells are grouped• composition of cell wall and it’s ability to absorb stain
General Characteristics• are found almost everywhere• are often pathogenic (they make us sick!)• are divided into groups according to:
–their shape–grouping–cell wall–ability to absorb stains
• Bacteria can be autotrophs or hetertrophs.
• Those that are classified as autotrophs are either photosynthetic, obtaining energy from sunlight or chemosynthetic, breaking down inorganic substances for energy .
• Bacteria classified as heterotrophs derive energy from breaking down complex organic compounds in the environment. This includes saprobes, bacteria that feed on decaying material and organic wastes, as well as those that live as parasites, absorbing nutrients from living organisms.
Oxygen Preferences
• obligate aerobes must have oxygen• obligate anaerobes cannot live in
oxygen• facultative anaerobes can grow with
or without oxygen
• Depending on the species, bacteria can be aerobic which means they require oxygen to live
or
• anaerobic which means oxygen is deadly to them.
Green patches are green sulfur bacteria. The rust patches are colonies of purple non sulfur bacteria. The red patches are purple sulfur bacteria.
Shapes of Bacteria
What a slide of Typical coccus looks like in a microscope.
Coccus
http://www.uleth.ca/bio/bio1010/Coccus1.jpg
Diplococcus
Streptococcus aurelius
Staphylococcus
Typical Bacillus
Bacillus
http://er1.org/docs/photos/Anthrax/bacillus%20anthracis%20-03.jpg
Typical Bacillus in a Microscope
Spirochetes
Gram Stain• A staining method to differentiate
bacteria
• Gram-negative refers to the inability to retain the deep violet dye
• Gram-positive refers to the ability to retain the deep violet dye
• The Gram stain, which divides most clinically significant bacteria into two main groups, is the first step in bacterial identification.
• Bacteria stained purple are Gram + - their cell walls have thick petidoglycan and teichoic acid.
• Bacteria stained pink are Gram – their cell walls have have thin peptidoglycan and lipopolysaccharides with no teichoic acid.
In Gram-positive bacteria, the purple crystal violet stain is trapped by the layer of peptidoglycan which forms the outer layer of the cell. In Gram-negative bacteria, the outer membrane of lipopolysaccharides prevents the stain from reaching the peptidoglycan layer. The outer membrane is then permeabilized by acetone treatment, and the pink safranin counterstain is trapped by the peptidoglycan layer.
Gram Staining
Gram Negative cells Gram Positive Cells
Is this gram stain positive or negative? Identify the bacteria.
Is this gram stain positive or negative? Is this gram stain positive or negative? Identify the bacteria.Identify the bacteria.
Bacteria Photos
Anthrax
Clostridium perfringes
Bacteria Photos
E. coliClostridium tetani
Bacteria Photos
Staphylococcus aureus
Neisseria gonorrhoeae
Bacteria Photos
Strep
• Bacteria can reproduce sexually by conjugation or asexually by binary fission.
Asexual Reproduction
• Binary Fission – cells grow in size the split in two…. Genetically identical
Sexual Reproduction (exchanging DNA) Conjugation
• two bacteria join together and exchange portions of DNA
F-Pilus for Conjugation
Transformation
DNA is taken in by a bacterium, and then used.
Transduction
DNA is transferred to a bacterium by a virus.
Endospore
• Bacteria can survive unfavorable conditions by producing an endospore.
Endospores• When
environmental factors become harsh bacteria will either die or form endospores.
• If bacteria have time, if the environmental changes are slow enough, they usually form endospores.
Examples of Symbiotic Relationships
• Mutualism – E. coli in the intestines of mammals aid in digestion.
• Parasitism – some bacteria are parasites. They live in a host and eventually overpopulate. As they do they use the host’s food and water, and eventually they starve the tissues.
Beneficial Uses/Effects
• chemical recyclers (Nitrogen Cycle)• the production of HGH, Insulin, Etc.,
through Genetic Engineering• oil spill cleanup• synthesis of Vitamins in your
intestines
• Bacteria are often maligned as the causes of human and animal disease. However, certain bacteria, the actinomycetes, produce antibiotics such as streptomycin and nocardicin.
Bacterial Diseases
• Anthrax• Botulism• Lyme Disease• Salmonella• Tetanus• Tooth decay• Tuberculosis
Strep Throat
Staph Infection
• Other Bacteria live symbiotically in the guts of animals or elsewhere in their bodies.
• For example, bacteria in your gut produce vitamin K which is essential to blood clot formation.
• Still other Bacteria live on the roots of certain plants, converting nitrogen into a usable form.
• Bacteria put the tang in yogurt and the sour in sourdough bread.
• Saprobes help to break down dead organic matter.
• Bacteria make up the base of the food web in many environments.
Streptococcus thermophilus in yogurt
Cyanobacteria
• are photosynthetic autotrophs that produce carbohydrates and oxygen
• tend to cling together in chains or colonies
• contain enzymes that allow them to “fix” atmospheric nitrogen
CyanobacteriaThis is a group of bacteria that includes some that are single cells and some that are chains of cells. You may have seen them as "green slime" in your aquarium or in a pond.
Cyanobacteria can do "modern photosynthesis", which is the kind that makes oxygen from water. All plants do this kind of photosynthesis and inherited the ability from the cyanobacteria.
Cyanobacteria were the first organisms on Cyanobacteria were the first organisms on Earth to do modern photosynthesis and they Earth to do modern photosynthesis and they made the first oxygen in the Earth's made the first oxygen in the Earth's atmosphereatmosphere..
http://www.mhhe.com/biosci/genbio/maderbiology7/graphics/mader07b/online_vrl/images/0510l.jpg
Filamentous: Chain of cells
http://www.spea.indiana.edu/joneswi/e455/Anabaena.jpg
Oscillatoria
http://botit.botany.wisc.edu:16080/images/130/Bacteria/Cyanobacteria/Oscillatoria/Oscillatoria_MC.jpg
Anabaena
_ http://www.bio.mtu.edu/~jkoyadom/algae_webpage/ALGAL_IMAGES/cyanobacteria/Anabaena_jason_dbtow17 2016.jpg
Some filamentous cyanobacteria have Heterocysts, which are Nitrogen-fixing structures
http://www.people.vcu.edu/~elhaij/IntroBioinf/Scenarios/heterocyst2.JPG
The role of bacteria in the Nitrogen cycle