Prokaryotes: Eubacteria & Archaea PDF

The Prokaryotes Eubacteria & Archaea  Bacterial Diseases in History… Tuberculosis (TB) Coughing, chest pain, fever, fatigue Was called consumption (weight loss) Found in Egyptian mummies Cure found in 1940s  Bacterial Diseases in History… Cholera Se...

The Prokaryotes Eubacteria & Archaea  Bacterial Diseases in History… Tuberculosis (TB) Coughing, chest pain, fever, fatigue Was called consumption (weight loss) Found in Egyptian mummies Cure found in 1940s  Bacterial Diseases in History… Cholera Several epidemics/pandemics Vomiting, diarrhea, deyration Due to limited access to clean water 3-5 million affected worldwide 58 000 – 130 000 deaths/year  Bacterial Diseases in History… Syphilis (“Great Pox”) First European outbreak in 1494 in Italy Recent outbreaks in Canada 1943  discovery of penicillin  Bacterial Diseases in History… Bubonic Plague (“Black Death”) Fever, painful lymph nodes 1330s  outbreak in China 1347  In Italy (spread through trade) In Europe, 25 million died (1/3 of population Greatly reduced with the introduction of antibiotics (1930s)  Bacterial Diseases in History… Anthrax Flu like symptoms Coughing up blood People can get sick with anthrax if they come in contact with infected animals or contaminated animal products. Can be used as a weapon of bioterrorism Bacterial Once upon a time, there were only 5 Kingdoms…  …and then in 1977 Carl Woese is a microbiologist credited with discovering archaea He determined that they weren’t just another taxon of the Kingdom Monera, but a new third domain  Kingdom Monera was split into two different kingdoms: Monera Archaea Eubacteria Cells are prokaryotic All cells are single-celled Cells do not contain membrane-bound organelles Cells have a single chromosome Cells reproduce asexually by binary fission  Archaea chemistry of cell membrane and cell wall very different from Eubacteria genetic information distinct from Eubacteria and eukaryotes Phylogeny of 3 Domains of Life  Archaea Methanogens – Microorganisms that produce methane as a metabolic by-product in anoxic (low oxygen) conditions – Found in wetlands, digestive tracts of animals Halophiles – Live in environments with very high salt concentrations  Extreme Thermophiles ‒ Prokaryotes that live in extreme environments. ‒ They can be found in high temperatures such as hot springs and hydrothermal vents. Psychrophiles ‒ Cold loving, live in temperatures below 15 degrees celsius  Prokaryotes single-celled organisms no membrane-bound organelles  Importance of Prokaryotes Pathogens: infectious bacteria that are responsible for many diseases in organisms Helpful roles in ecosystems and organisms: decomposers, producers, recycle nutrients and involved in biogeochemical cycles Commercial uses: used to make cheese, soy sauce, yogourt and chocolate!  Bacterial Diseases scarlet fever (Streptococcus pyogenes) tetanus (Clostridium tetani) botulism (Clostridium botulinum) anthrax (Bacillus anthracis) cholera (Vibrio cholerae) etc. Eubacteria  Eubacteria Common characteristics: single loop of DNA + plasmids (a single loop of DNA with a small number of genes, not essential for cellular function) ribosomes one or more flagella, small hairlike pili complex cell walls with peptidoglycan Extremely diverse domain… Shapes  Metabolism obligate aerobes: require oxygen facultative aerobes: aerobic respiration when oxygen is present and anaerobic respiration or fermentation when oxygen is absent obligate anaerobes: cannot live where oxygen is present  Reproduction BOTH eubacteria and archaea reproduce by BINARY FISSION: the single strand of bacterial DNA replicates the bacterium produces a cross wall the newly reproduced DNA is transferred to the new cell and the bacterium divides into two identical cells  Reproduction binary fission is an example of vertical gene transfer: genetic information is transferred from parent to daughter cell bacteria also share information via horizontal gene transfer: genetic information is transferred from a donor to recipient cell  Reproduction examples of horizontal gene transfer include: o transformation  when a bacterial cell takes in and uses pieces of DNA from its environment o transduction  when a virus transfers DNA from one bacterium to another o conjugation  sexual reproduction in which two cells join to exchange genetic information Antibiotics & Resistance ABCTV Catalyst: Antibiotic Resistance