I. BacteriaI. BacteriaA. Introduction

B. Various functions/roles of bacteria

C. Diseases caused by bacteria

D. Classification of bacteria

E. Metabolism

F. Structure of bacteria

G. Reproduction

A. Introduction

1. Thought to cause human and animal disease

2. actinomycetes, produce antibiotics such as streptomycin and nocardicin;

3. Some live symbiotically in the guts of animals (including humans-ecoli

Leptospira-disease in livestock

Intro. Cont.

4. Bacteria put the tang in yogurt5. Put the sour in sourdough bread6. break down dead organic matter7. bacteria make up the base of the food web in many

ecosystems8. extreme flexibility, capacity for rapid growth and

reproduction, and great age-they have been around a very long time!

9. nearly 3.5 billion years old-are fossils of bacteria-like organisms.

B. Functions/Roles of Bacteria1.1. Nitrogen fixationNitrogen fixation

a. convert nitrogen into a usable form on the roots of plantsa. convert nitrogen into a usable form on the roots of plants

2.2. Recycling of nutrientsRecycling of nutrients

a. break down dead organic mattera. break down dead organic matter

3.3. FoodsFoods

a. Used in food to put the tang in yogurt and the sour in a. Used in food to put the tang in yogurt and the sour in sourdough breadsourdough bread

4.4. MedicinesMedicines

a. produce antibioticsa. produce antibiotics

5.5. Cause diseaseCause disease

6.6. Genetic Engineering!!!!Genetic Engineering!!!!

C. Diseases Caused by BacteriaC. Diseases Caused by Bacteria

D. Classification of Bacteria

1. Kingdoma. Monera

2. Phylums:

a.a. ArchaebacteriaArchaebacteriab.b. EubacteriaEubacteria

3. Archaebacteria3. Archaebacteria

a)a) Known as the Known as the extremophilesextremophiles

b)b) Live in extreme Live in extreme environments that environments that would kill other would kill other microbesmicrobes

c)c) Also know as the Also know as the ancient bacteriaancient bacteria

4. Extreme 4. Extreme ThermophilesThermophiles

d)d) Extreme Extreme ThermophilesThermophiles

Hot potsHot pots Hydrothermal ventsHydrothermal vents

e)e) High temperaturesHigh temperaturesf)f) SulfurSulfurg)g) Thermus Aquaticus Thermus Aquaticus

–taq polyermase –taq polyermase used in PCRused in PCR

Hot spring (yellow patches are mats of microbial growth)

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d. Examples of Extremophilesd. Examples of Extremophiles

i.i. ThermophilesThermophiles 1)1) high temperature (80 degrees to high temperature (80 degrees to 105 degrees C) for growth105 degrees C) for growth

2)2) Sulfur-oxidizers grow at low pH Sulfur-oxidizers grow at low pH (less than pH 2) because they (less than pH 2) because they acidify their own environment by acidify their own environment by oxidizing S (sulfur) to Hoxidizing S (sulfur) to H22SOSO44

(sulfuric acid).(sulfuric acid).

3) inhabitants of hot, sulfur-rich environments associated with volcanism, such as hot springs, geysers etc.

4) Yellowstone National Park, and thermal vents ("smokers") and cracks in the ocean floor examples

e. Extreme Methanogense. Extreme Methanogensa)a) Methanogens liveMethanogens live

marshes marshes lake sedimentslake sediments digestive tracts digestive tracts

mammals (cows)mammals (cows) sewage disposal sewage disposal

plants.plants.

b)b) Natural GasNatural Gas

e. Extreme Methanogense. Extreme Methanogens

c) methanogens produce methane (CH4)

d) metabolism created most the natural gas (fossil fuel) reserves that are tapped as energy sources for domestic or industrial use

e) can be exploited to produce energy from waste materials

f. Extreme Halophilesf. Extreme Halophiles1)1) locations locations

Dead SeaDead Sea Great Salt LakeGreat Salt Lake Evaporating PondsEvaporating Ponds

2)2) Salt lovingSalt loving3)3) Halobacterium halobiumHalobacterium halobium

Purple membrane bacteriorhodopsin heterotrophs

f. Extreme Halophilesf. Extreme Halophiles

1) Halobacterium halobium, prevalent in the Great Salt Lake, adapts to the high-salt environment by the development of "purple membrane",

2) pigment in the plasma membrane rhodopsin called bacteriorhodopsin reacts with light in a way that forms a proton gradient on the membrane allowing the synthesis of ATP.

3) Absorb green light and reflect red and blue

4) Evolutionary link to photosynthesis

Eubacteria-true Eubacteria-true bacteriabacteria

E. MetabolismE. Metabolism1.1. Obligate aerobesObligate aerobes

a.a. Require oxygenRequire oxygenb.b. Mycobacterium Mycobacterium

tubberculosistubberculosis tuberculosistuberculosis

2.2. Obligate anaerobesObligate anaerobesa.a. Killed by oxygenKilled by oxygenb.b. Treponema pallidiumTreponema pallidium

SyphilisSyphilisc.c. Clostridium botulinumClostridium botulinum

BotulismBotulism3.3. Both with or without oxygen Both with or without oxygen

(facultative)(facultative)a.a. cellular respirationcellular respirationb.b. fermentationfermentation

SyphilisSyphilis

BotulismBotulism

E. MetabolismE. Metabolism

4.4. HeterotrophsHeterotrophsa)a) Use organic molecules as food sourceUse organic molecules as food source

b)b) ParasitesParasites Obtain nutrients from living organismsObtain nutrients from living organisms

a)a) SaprophytesSaprophytes

Feed on dead organismFeed on dead organism organic wastesorganic wastes Recyclers or decomposers-contain Recyclers or decomposers-contain

cellulase enzymescellulase enzymes

E. MetabolismE. Metabolism

5.5. Photosynthetic AutotrophsPhotosynthetic Autotrophsa.a. Use Sunlight to make foodUse Sunlight to make food

Live in Ponds, streams, moist areas of landLive in Ponds, streams, moist areas of land

b.b. CyanobacteriaCyanobacteria

c.c. Blue-green, red or yellowBlue-green, red or yellow

d.d. Chains of independent cells Chains of independent cells

Eubacteria Chemosynthetic AutotrophsEubacteria Chemosynthetic Autotrophs

Make food from chemosynthesisMake food from chemosynthesis SulfurSulfur NitrogenNitrogen

Convert unusable atmospheric nitrogen into nitrogen containing Convert unusable atmospheric nitrogen into nitrogen containing compounds plant can use.compounds plant can use.

nitrogen fixationnitrogen fixation by bacteria such as by bacteria such as RhizobiumRhizobium Convert sulfur to sulfuric acidConvert sulfur to sulfuric acid Sulfur-oxidizers grow at low pH (less than pH 2) because they acidify their

own environment by oxidizing S (sulfur) to H2SO4 (sulfuric acid). Why Yellowstone stinks!

F. Bacterial Structure F. Bacterial Structure

1.1. Very small cellVery small cell

2.2. Lack membrane bound organellesLack membrane bound organelles RibosomesRibosomes

3.3. Lack nuclear membraneLack nuclear membrane DNA circularDNA circular NucleoidNucleoid

4.4. Biochemical processes in cytoplasmBiochemical processes in cytoplasm

5.5. Plasmids –loops of DNAPlasmids –loops of DNA

Typical Bacteria CellTypical Bacteria Cell

Electron Electron MicrographMicrograph

of of E. ColiE. Coli

PlamidsPlamids

G. Reproduction

1. Asexual

2. sexual

1. Asexual1. Asexual

a.a. BINARY FISSIONBINARY FISSIONb.b. Asexual ReproductionAsexual Reproduction

Copies chromosomeCopies chromosome Attach to cell’s plasma Attach to cell’s plasma

membranemembrane

c.c. DOUBLING THEIR DOUBLING THEIR NUMBERS EVERY NUMBERS EVERY 20 MINUTES20 MINUTES

d.d. **favored for genetic **favored for genetic engineering**engineering**

19281928

Fleming Fleming discovers penicillindiscovers penicillin the first antibiotic.the first antibiotic. Inhibits cell wall Inhibits cell wall

growth! growth!

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