Microbiology 205 Gary W. Childers Biology BLD 238 (old Building) Ph Introduction to Microbiology

What is Microbiology? What are they? How we classify Microorganisms What do they do? Importance to earth, ecology, and humans Where do they do it? Niche / environment / tolerances How we study Microorganisms Tools and techniques to study microbiology

Bacteria Archaea Algae Protozoa Fungi Viruses Prokaryotes Eukaryotes ? Protista Definition of Microbiology Study of microorganisms and their interactions

Tree of Life Tree of life consists of 3 Domains 2 of the 3 are exclusively microorganisms 1 (Eucarya) is both micro and macroscopic

Tree of Life based on comparison of Ribosomal nucleotide sequences

Figure 1.4 Diagram of Stanley Miller’s apparatus

500 ml water (Ocean) Gases (CH4, NH4, H2) ATM Condenser (rain) 60,000 volt spark (Lightning) Continuous recycling Tarry liquid AA, acetate, formate

Comparison of Prokaryotes and Eukaryotes: Feature:ProkaryotesEukaryotes SizeSmall ( µM)Large (5-20 µM) OrganellesNOYes DNACircular/haploidLinear/diploid Ribosomes70S 50S 30S80S 60S 40S (RNA)5S 23S 16S5.5S 5S & 28S 18S Morphologysingle cellsingle/multicellular Cell WallYesyes/no FlagellaYes/no-one fibrilyes/no- 9+2 centrioles Cell Membrane bilayer/monlayerbilayer ester/etheresterFA/glycerol

Prokaryote vs Eukaryote

Contrast Bacteria Archaea Morphology rods/cocci/spirals/filaments SizeµM µM Cell wallPeptidoglycanNo PTG Ribosomes70s70s PolymeraseProkaryotesEukaryotes ReproductionBinary fissionBinary Fission FeedingSaprotrophicallySaprotrophically

Classification of Microorganisms By Nutrition Chemotrophs Acquire Energy (E) from Chemical Compounds Chemoheterotrophs E for organic Compounds (Glucose) Carbon (C) for synthesis from organic Compounds Chemoautotrophs (chemolithotrophs E from inorganic compounds (Hydrogen) C for synthesis from Carbon Dioxide (CO2) Phototrophs: Acquire E from sunlight Photoheterotrophs E from Sunlight C for synthesis from organic substrates Photoautotrophs (Photolithotrophs) E from sunlight C for synthesis from CO2

Hallmarks of Bacteria Small size Single celled Asexual reproduction Unrestricted growth Metabolic diversity

Common morphologies of microorganisms

Size of microorganisms

100 microns ~ 100 E.coli lined up end to end

100 microns ~ 100 E.coli lined up end to end

Large surface area facilitates transport of nutrients

Microbes are efficient “machines”

What do microorganisms do? What are their role in the Biosphere 1.Disease- 5% of described microorganisms 2.Biogeochemical Reactions-Nutrient cycles C, N, S 3.Symbionts Plants Rhizophere/bacteria Mycorrhizae/fungi Animals bacteria/archaea Ruminants (ex: cow) and ruminant microorganisms (ex: Fibrobacter) also: termites/spirochetes, humans/gut bacteria 4. Food/Agriculture Nitrogen fixing bacteria (Rhizobium spp., Azotobacter spp., Nostoc spp.) Dairy/Bread/Alcohol/Solvents (fermenters, yeast, lactic acid bacteria, clostridium) (Glucose  acetic acid, lactic acid, citric acid, ethanol, carbon dioxide) 5. Sewage treatment 100% 6. Research Biotechnology (large scale bioreactors, acid mining, biofuels) Recombinant DNA (cloning, drug discovery) Bioremediation (oil spill remediation, explosives degradation)

Symbiosis ex: Photobacterium spp.

+VFA’s

Unique Metabolic Diversity 1. Fix atmospheric nitrogen 2. Synthesize Vitamin B Use inorganic energy sources: NH 4,H 2 S, H 2, Fe +2, SO 4, S° 4. Photosynthesize without chlorophyll/bacterial rhodopsin 5. Utilize inorganic and organic Terminal Electron Acceptors as an alternate to Oxygen CO 2, NO 3, SO 4,Mn +4, Fe +3, Fumarate, humic acids 6. Extensive capacity for Anaerobic growth 7. Use H 2 S, H 2 or organic compounds as electron donors for photosynthesis 8. Growth at high temperatures/salt/pressure

Where Microorganism do it 1. Micro site / Niche: Place of Business / Their profession Environmental Tolerances Range of Activity Cardinal Points Minimum/Optimum/Maximum Substrate Limitations Range of Substrates Affinity Growth Rate

Terms used to describe microbial niche, or environment 1.Tolerant/Facultative/Obligate 2.pH : Acidophile/neutrophile/Basophile 3.Oxygen: Aerobic/Anaerobic/facultative 4.Temperature: Psychrophile/Mesophile/Thermophile 5.Osmotic: Halophile/Osmophilic/ Xerophile 6.Substrate: Oleogotrophic/Capiotrophic

How Do We Study Microorganisms? 1.Parameters Growth Rate (GT, µ) Enumerations Measure Substrate Disappearance/Product Formation) 2. Scientific Method Controls variables Optimum Conditions 3. Equipment Molecular Techniques Microscopes Gas Chromatographs

How do we study Microorganism? Substrate + oxidant--  Product + Cells + Waste Electron Donor (ED) + Terminal Electron Acceptor (TEA)-  (reduced)(oxidized) oxidized product + REDUCED oxidant + CELLS + ATP Heterotrophic aerobic respiration: C 6 H 12 O 6 + 6O 2  6CO 2 + 6H 2 O + release of energy (glucose) Fire: CH 4 + O 2  H 2 O + CO 2 + release of energy