science A based largely on an artifact.
Over one hundred years ago Robert Koch made one of the most important conceptual and technological breakthroughs in the history of microbiology with the discovery of methods for the production of solid nutrient media and the ability to isolate pure cultures of microorganisms. The importance of this discovery to advances in medical, agricultural and industrial microbiology would be hard to overestimate. The dividends these techniques returned have positively affected the lives of nearly everyone on the planet. The training of generations of microbiologists has been based, to a significant degree, on the investigation of the properties of pure cultures and the elucidation of the properties of these organisms one at a time. As productive as this strategy has been it perpetuates an astonishingly erroneous conception. In fact, pure cultures are absent or virtually so in nature.
Photo Courtesy of the National Library of Medicine.
Announcments
Review session tonight in room 1040 Plant Sciences
Goals
Understanding the role of microorganisms in the Environment. Knowing the types of ecosystems that are present on this planet. Knowing what types of microorganisms would be found in the various ecosystems. How do bacteria compete with each other? Being able to describe how a sewage treatment facility works. Understanding the relationship between bacterial metabolism and the environment What metabolic pathways would you expect to be utilized by microorganisms growing in the various ecosystems found on this planet? It is essential that each microorganism possess a complete metabolic pathway? How can microorganism cooperate in bioremediation? How does bioaugmentation facilitate bioremediation?
Mutualistic re lationship be e bacte twe n ria and e ukaryote s
n Nitroge fixation ym lationship be e bacte spe s and twe n rial cie S biotic re plants ss n Allow theplant acce to utilizablenitroge s ria nts Plant provide bacte with nutrie
What happens in a cell when one of the enzymes in a metabolic pathway is absent?
What cellular structures could bacteria use to begin a biofilm?
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1. 2. 3. 4. 5. 6.
LPS. Flagella. Pili. Capsule. All of the above. I dont know.
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Nutrients are limiting
In the Lab in BATCH culture under optimal conditions the population doubling time for E. coli is 20 minutes! How long is the population doubling time for E.coli in its natural habitat?? The Intestine?
12 hours!
Changes in environment will effect bacterial growth! AND the environment (remember Biosphere 2)
http://www.pbs.org/opb/intimatestrangers/about.html
What phase of growth do industrial microbiologists collect primary metabolite products?
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1. 2. 3. 4.
Lag phase Exponential phase Stationary phase Death phase
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Environmental Microbiology
Microbes are nature's decomposers. Environmental Microbiologists study ways to maximize the efficiency of microbes in helping to remove various kinds of wastes (bioremediation) Environmental Microbiology brings together engineers, geologists and hydrologists, and microbiologists, public health officials.
What happens after you Flush?
The toilet. The commode. The john. The loo. The porcelain throne. No matter what you call it, every home has at least one. But more importantly, how is the waste generated rendered safe.
Why do we need a sewer system?
Sewage
Components
Wastewater Organic matter Chemicals Bacteria Viruses
Goals of S wagetre e e atm nt
duction of biological oxyge de and (BOD) nm Re
ount of O2 re quire to e inateorganic m r in a d lim atte Am sam ple wagecontains organic m r, bacte can utilizeit atte ria I f se f or m tabolism e
WhatWhat wagebefe ofe ofrobic re Caretheproducts anae ae an S aretheproducts d? robic spiration? e rm nte re spiration
Bacterial growth
Aerobic respiration
Reduction of NADH via the Electron transport chain Utilizes O2 as a terminal electron acceptor
Anaerobic respiration
Reduction of NADH via Electron transport chain Utilizes something other than O2 as a terminal electron acceptor
Fermentation
no electron transport chain Operates in the presence or absence of Oxygen Uses organic molecule as the terminal electron acceptor
Why are manhole covers round?
Because it avoids accidents. Since manhole covers are round, it is impossible for a cover to fall down the manhole. If they were square or rectangular, they could.
Kimchee Production
Kimchee is a popular Korean food produced by pickling Chinese cabbage (Brassica pe nsis) in thepre nceof ce kine se rtain spice s. 1. C thele s of half a he (500 g) of Chine cabbageinto 5-7 m chunks, chop 1/2 re chili ut ave ad se m d pe r, thinly slice1 cloveof garlic ppe 2. Add m ixturewith 10 g of salt (non-iodize to a 2-lite plastic soda bottle cut just be the d) r , low t op of thebottle . 3. Forma sliding se by placing a Pe dish lid, rimup, on top of theingre nts. al tri die 4. C pre theingre nts to 2/3 to 1/2 thevolum of thebottleby pre om ss die e ssing down on thesliding se e ry 15 m al ve inute for an hour or two. As thesalt "draws" liquid fromthece of the s lls cabbage fluid will appe in thebottle as you com ss theingre nts, this fluid will flow , ar ; pre die ove thetop of thelid and air will bubbleout around thee . r dge 5. I nse thetop of thesoda bottle(scre cap "up") into thebottleabovethesliding se rt w al. 6. Le se , undisturbe for 7 days tt d
Food fermentation does all of the following except
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a. b. c. d.
give foods a characteristic taste. lower the risk of food spoilage. sterilize foods. increase the shelf life of the food
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Industrial fermentation
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a. always involves alcohol production. b. involves the large-scale production of any beneficial -compound. c. refers to the oxidation of sugars using organic electron -acceptors. d. is any desirable change to food by microbial metabolism.
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Industrial Microbiology
Bioremediation
Uses organisms to clean up toxic, hazardous, or recalcitrant compounds by degrading them to harmless compounds Most widely known application is the use of bacteria, such as Pseudomonas, to clean oil spills