Bacteria Characteristics of LUCA last universal common ancestor

Bacteria


Characteristics of LUCA (last universal common ancestor) Members of all the domains: • Conduct glycolysis • Replicate DNA conservatively • Have DNA that encodes peptides • Produce peptides by transcription and translation using the same genetic code • Have plasma membranes and ribosomes

Structure: Procaryotic. ) Prokaryotic cells differ from eukaryotic cells. Prokaryotes lack a cytoskeleton; divide by binary fission. DNA is not in a membrane-enclosed nucleus. DNA is a single, circular molecule. Prokaryotes have no membrane-enclosed organelles.

Cell wall; unique and varied Gram positive gram negative Lipid bilayer inside( porous) lipid bilayer, glycoprotein Glycoprotein outside outer lipopolysaccharide (impervious) many resistant to antibiotics.

Reproduction: can divide, and can come together and share some genetic information.

Sex is bacteria – haploid (one set of information) ring dna – one dna strand only

Classic view; identified by morphology; Bacillus anthracis; rod shaped

Spirillum : spiral shaped

Merismopedia: cocci. round, and here colonial

Nostoc, cyanobacteria. ; photosynthetic

New view: based on biochemistry. Recognition of tremendous variety in metabolic systems energy carbon source Photoautotroph light CO 2 Photoheterotroph light organic C Chemolithotroph inorg. CO 2 Chemoheterotroph org. C org C both live and dead source of energy Corresponds to plant, animal, fungi Also, some are aerobes, some anaerobes, some can do both.


Distances represent biochemical diversity; Note all eucayotes beyond protozoa are very close! Homo = Human =all animals Coprinus = mushroom Zea = corn, all higher plants Parmecium = eucaryotic protist Porphyra = red algae Costaria = brown algae

Lateral gene transfer and domains Why are three domains oddly different yet similar?

LETTER Nature Genetics 29, 54 - 56 (2001) Published online: 13 August 2001; | doi: 10. 1038/ng 708 Comparable system-level organization of Archaea and Eukaryotes J. Podani 1, 2, Z. N. Oltvai 1, 3, H. Jeong 4, B. Tombor 3, A. -L. Barabási 1, 4 & E. Szathmáry 1, 2 1 Figure 1. Analyses based on information transfer pathways. a−d, NMDS ordinations. e, g, OC classifications. f, h, UPGMA classifications. i, j, unrooted NJ trees. (a, b, e, f, i) represent data based on substrate list; (c, d, g, h, j) are based on enzyme variables. (a, c, e, g) represent ordinal information; (b, d, f, h, i, j) represent P/A information. A, Archaea; B, Bacteria; E, Eukarya.

Figure 2. Analyses based on metabolic pathways. a−d, NMDS ordinations. e, g, OC. f, h, UPGMA classifications. i, j, unrooted NJ trees. (a, b, e, f, i) represent data based on substrate list; (c, d, g, h, j) are based on enzyme variables. (a, c, e, g) represent ordinal information; (b, d, f, h, i, j) represent P/A information. A, Archaea; B, Bacteria; B 1, nonparasitic bacteria; B 2, parasitic bacteria; E, Eukarya. The arrow in (f) indicates the location of the Crenarchae A. pernix.

Possibility of lateral gene transfer between species. Importance: movement of genes from one species to another = gm crops?

• Prokaryotes are the most successful organisms on Earth in terms of number of individuals. • The number of prokaryotes in the ocean is perhaps 100 million times as great as the number of stars in the visible universe. • They are found in every type of habitat on Earth. • Every procaryote is infected by viruses, so a lot more viruses than anything else.

Importance of bacteria. 1. Ocean plankton – photosynthetic - add Iron – reduce C 02 in atmosphere 2. Nitrogen fixation – N 2 – usable forms 3. 3. Decay – breakdown of organic molecules 4. 4. Fermentation – the glory of wine and beer 5. 5. Environmental cleanup – archaea.

6. Disease issues infertility – Chlamidia atherosclerosis – arterial plaque kidney stones stomach ulcers – heliobacter (Barry Marshall) cystic fibrosis – protection against typhoid 7. Bird flu – why worry? 8. Influenza – why will we never eliminate it. 9. When should a bacteria (disease) kill quickly? When slow? 10. Antibiotic resistance




Dental Plaque = colony of bacteria in a biofilm.

Purification of water supply 1. Typhoid – recognition of tainted water transmission 2. What is clean water? Amount of fecal bacteria. 3. Sewage treatment 4. Water treatment – improvement with time until today. 5. Where is the water supply safest and why?

Classic issue of Bad water and disease. London 1854

Solutions ; Sewage Treatment 0. put sewage somewhere else (Chicago solution) 1. Primary treatment – get rid of solids what to do with them? 2. Secondary treatment – bacterial digestion – leaves nutrients reclaimed water for golf courses 3. Tertiary treatment – chemical carbon filter, electrolytes What to do with the water? Costs: primary - $. 05 per 1000 gallon secondary$. 10 per “ “ tertiary $. 50 per 1000 gallons The reason Clean Water Act only went to Secondary treatment.

Problems with water • Non-point sources of pollution dogs, cats, etc. high nutrients = algal growth leads to bacterial growth

How to purify water • 1872 – filter through sand • 1896 – chlorination, chlorine gas now we use ozone, other oxidants • Today – aerate, chlorinate, settle, filter, rechlorinate, etc.

The explanation for ‘swimmer’s or surfer’s ear


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