Kingdom Archaebacteria Ancient organismsAncient organisms Cell wall lacks peptidoglycanCell wall lacks peptidoglycan –A protein-carbohydrate wall Found in extreme environmentsFound in extreme environments –i.e. swamps, salt lakes, & hot springs Filamentous cyanobacterium, Anabaena sp.
Methanogens Unique method of harvesting energy by converting H 2 and CO 2 into methane gasUnique method of harvesting energy by converting H 2 and CO 2 into methane gas Live in anaerobic (no oxygen) environment like swamps and human intestinesLive in anaerobic (no oxygen) environment like swamps and human intestines Source of swamp gasSource of swamp gas A. Methanosarcina (cocci) and Methanosaetacocci
Extreme halophiles Salt-loving archaebacteriaSalt-loving archaebacteria Live in high salt concentrationsLive in high salt concentrations –i.e. Great Salt Lake & Dead Sea Use salt to generate ATPUse salt to generate ATP treiben-floating-swimming-in-on-salt-lake-city-utah-usa-dscn6689.jpg
Most extreme halophiles discovered (Nov 19, 2003) The world's most alkaline life forms are living in contaminated water in the US. Scientists found microbial communities thriving in the slag dumps of the Lake Calumet region of southeast Chicago where the water can reach a pH of Living in this extreme environment is comparable to swimming in caustic soda or floor stripper, the researchers say. They found the microbes while studying contaminated groundwater created by more than a century of industrial iron slag tipping in Illinois and Indiana. Picture: A phase-contrast microscope view of the newly-found halophiles.
Thermoacidophiles Live in extremely acidic & high temperaturesLive in extremely acidic & high temperatures –i.e. hot springs, volcanic vents or hydrothermal vents
Kingdom Eubacteria ProkaryoteProkaryote Cell wall has peptidoglycanCell wall has peptidoglycan UnicellularUnicellular Anthrax
cocci Streptococci – chains of cocci Staphylococci – grape-like clusters of cocci
How to differentiate bacteria? Staining reveals the difference in cell wallStaining reveals the difference in cell wall Gram-positive stays purpleGram-positive stays purple Gram-negative becomes pinkGram-negative becomes pink
Comparing gram-neg & gram-pos
Gram-pos has thicker layer of peptidoglycan so retain stain (purple) which means that: -they have different susceptibilities to antibacterial drugs -they produce different toxic materials -they react differently to disinfectants
Phylum Cyanobacteria Some are photosyntheticSome are photosynthetic Once known as blue-green algaeOnce known as blue-green algae Eutrophication or population bloom – sudden increase in cyanobacteria due to nutrients in waterEutrophication or population bloom – sudden increase in cyanobacteria due to nutrients in water Cyanobacteria die and decompose by heterotrophic bacteria Heterotrophic bacteria consume all oxygen Causes organisms i.e. fish to die from lack of oxygen
A worldwide study in 2005 noted an increase in eutrophication, which was blamed for the death of these fish in a lake near Bangalore, India. Alabama Oklahoma
What's at stake - extensive eutrophication (algal growth fueled by nutrients running off agricultural fields and from urban areas) spreading into the Gulf of Mexico off the coast of Florida. Intact ecosystems, including mangrove swamps, help prevent eutrophication and the problems it caused.
Phylum Spirochetes Gram-negativeGram-negative Spiral-shapedSpiral-shaped HeterotrophicHeterotrophic Causes syphilis (STD)Causes syphilis (STD) >36,000 cases in US in 1999 (increasing)
Phylum Gram-Positive Bacteria milk becomes yogurt when bacilli are addedmilk becomes yogurt when bacilli are added Found in – oral cavity & intestinal tractFound in – oral cavity & intestinal tract –Some cause tooth decay or strep throat
Phylum Proteobacteria Largest, most diverse group of bacteriaLargest, most diverse group of bacteria Enteric bacteria – E. coli – lives in human intestines – produces vit.K and assists breakdown of foodEnteric bacteria – E. coli – lives in human intestines – produces vit.K and assists breakdown of food Chemoautotrophs – use chemicals to get energyChemoautotrophs – use chemicals to get energy Nitrogen-fixing bacteria – symbiotic relationship with plants – plant needs nitrogen, bacteria needs plantNitrogen-fixing bacteria – symbiotic relationship with plants – plant needs nitrogen, bacteria needs plant –Rhizobium
Bacterium remembered NO membrane bound organellesNO membrane bound organelles NO true nucleusNO true nucleus