BOLOGY 107 Lecture 34Outline of Last Lecture I. Bacteria and Archaeaa. Genetic transfer in bacteriab. Antibiotic resistanceRapid adaptation Outline of Current Lecture II. Bacteria and Archaeaa. Why is resistance spreading?b. Prokaryotic metabolismc. Archaead. Roles of bacteriaIII. Viruses Current LectureBacteria and Archaea1) Why is resistance spreading?a) Overuse and incorrect use of antibioticsi) Clinical, agricultural, householdb) Antibiotics select for resistant bacteriai) Resistant cells can pass their resistance to other bacteria via conjugation or transformation2) Prokaryotic Metabolisma) Divided by energy sourcei) Phototrophs- energy from lightii) Chemotrophs- energy from chemicalsb) Divided by carbon sourcei) Autotrophs- don’t need a carbon sourceii) Heterotrophs- need an organic carbon source(1) Expressed in combos of the two divisions – chemoautotropsc) Oxygen metabolismi) Obligate aerobes – require oxygen ii) Obligate anaerobes – poisoned by oxygeniii) Facilitative aerobes – can live in either environmentd) Nitrogen fixationi) Conversion of N2 to NH3These notes represent a detailed interpretation of the professor’s lecture. GradeBuddy is best used as a supplement to your own notes, not as a substitute.(1) Used in amino acid synthesis and DNAii) Nitrogen fixing bacteria can make nitrogen available for plants(1) Allows them to grow in low-nitrogen soilse) Metabolic cooperationi) Colonies help each other(1) Some cells can specialize(2) Channels allow an exchange of materials(3) Chemical signals are released for communication and recruitmentii) Can cooperate with other organisms(1) Humans and the bacteria in the gut3) Archaea a) First discovered in “extreme” environmentsi) Dubbed ‘extremeopiles’ii) Excellent at adaptingb) They are prokaryotes with similar characteristics to both eukaryotes and bacteriac) Divisions i) Halophiles – very high salt environmentsii) Thermophiles – very high temperature environmentsiii) Methanogens – produce methane4) Roles of bacteriaa) Decomposersi) Break dead organisms, make nutrients availableb) Pathogens i) Cause half of human diseases(1) Most symptoms caused by bacterial toxins(a) Exotoxins – proteins secreted by live bacteria(b) Endotoxins – release of toxins from dead bacteriac) Research and technologyi) Molecular biology – manipulate DNAii) Pharmaceuticals – produce drugsiii) Bioremediation – remove pollutantsiv) Polymer synthesis – create natural plasticsViruses5) Obligate intercellular parasitesa) Consist of DNA or RNA genome and protein coatb) Large diversity of structure and genetic materialc) Cannot replicate on their
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