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Chemolithotrophic proteobacteria S and Iron oxidizing • • • • • (SCIENCE 284: 16 April 1999) Thiomargarita namibiensis Beggiatoa (Winogradsky column) Thiothrix/Thioplaca Thiobacillus endosymbionts of deep-sea vent invertebrates Quiz 1. Why is 16S rRNA such a good molecule for making phylogenetic trees (give 2 good reasons). (3) 2. What is the evolutionary distance between these two sequences. You may define it as a %. GGCCCTATATAC GCGCCTTTATAC (2) 3. Chloroplasts were originally _______, and are proof for theory of ________ (2) 4. Name three different ways to define a bacterial species (3) Nitrifiers • Nitrosonomas and Nitrobacter • Winogradsky Hydrogen oxidizers • Alcaligenes ”Knallgas reaction“ • 2 H2 + O2 ---- 2 H2O Methanotrophs and Methylotrophs • Not all methylotrophs are methanotrophs • Use methanol, methylamine, formate and (methane) • Type 1 (ribulose monophosphate pathway) and II (serine pathway), membranes differ too – Type 1 membranes are throughout cell – Type II on periphery of cell • Endosymbionts in deep-sea vent mussels Photosynthetic proteobacteria • Purple phototrophic proteobacteria (bacteriochlorophylls and photophosphorylation) • Purple sulfur, eg. Chromatium • Below is Chromatium tempedium from Yellowstone, that grows above 50C. Notice the phase-bright sulfur granules • Purple non-sulfur (photoheterotrophs) • (other groups in the Bacteria that photosynthesize?, green sulfur, green filamentous, cyanobacteria) Spirilla: • Spirillum _some magnetotactic e.g. Magnetospirillum p 487 • Bdellovibrio, attack gram – bacteria, see developmental cycle Sulfate/sulfur reducers • Desulfurovibrio, Desulfuromonoas, anoxic habitats, compete with methanogens • use, H2, lactate as e'donors and sulfate or sulfur as e'acceptor. What is the product? Budding and stalked • Hyphomicrobium (methylotroph), budding • Caulobacter, stalked, see cycle Sheathed Proteobacteria: • e.g Leptothrix • Mn 2+ + 0.5 O2 + H2O --- Mn O2 + 2H+ delta G –68kJ Fermentative rods and vibrios 1.Enterics (gamma) • Gram -, nonsporulating, facultative aerobes, fermentative, opportunistic pathogens • 2 types: mixed acid fermenters (produce acid) E. coli OR 2,3-butanediol fermenters (produce neutral products) Enterobacter aerogenes/Erwinia Escherichia Salmonella typhi- typhoid fever Serratia marcescens (Bright red pigment- prodigiosin) Xenorhabdus (bioluminescence) Klebsiella pneumoniae (not normally pathogenic) Vibrio, Photobacterium • V. cholerae • Photobacterium – O2 required for luciferase activity – Quorum sensing – FMNH2 + O2 +RCHO ---- FMN +RCOOH + H2O + hv – Need flavin mononucleotide, aliphatic aldehyde, O2, and enzyme. E- donor is NADH Oxidative rods and cocci • Pseudomonads (human pathogens, biodegraders, plant pathogens) • Azotobacter and free-living N-fixers • Rhizobium and Bradyrhizobium: symbiotic Nfixers • Agrobacterium, crown gall • Acetobacter and Gluconobacter • Legionella, • Neisseria • Rickettsia obligate parasite, Rocky mountain spotted fever