View
213
Download
0
Tags:
Embed Size (px)
Citation preview
Bacteria
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
Characteristics of LUCA (last universal common ancestor)
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.
Gram positive gram negative
Lipid bilayer inside( porous) lipid bilayer, glycoprotein
Glycoprotein outside outer lipopolysaccharide (impervious)
many resistant to antibiotics.
Cell wall; unique and varied
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 source
Photoautotroph light CO2
Photoheterotroph light organic C
Chemolithotroph inorg. CO2
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 the three domains oddly different yet similar?
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.
LETTER Nature Genetics 29, 54 - 56 (2001) Published online: 13 August 2001; | doi:10.1038/ng708 Comparable system-level organization of Archaea and EukaryotesJ. Podani1, 2, Z.N. Oltvai1, 3, H. Jeong4, B. Tombor3, A.-L. Barabási1, 4 & E. Szathmáry1, 2 1
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; B1, nonparasitic bacteria; B2, 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 C02 in atmosphere
2. Nitrogen fixation – N2 – usable forms
3. Decay – breakdown of organic molecules
4. Fermentation – the glory of wine and beer
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
Question: who has the purest water, Los Angeles or Aspen, Colorado??