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 N-fixers Agrobacterium, crown gall Acetobacter and Gluconobacter Legionella, Neisseria Rickettsia obligate parasite, Rocky mountain spotted fever