Microbiology FS – Bacterial Anatomy and Physiology Reading Outline

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Bacterial Anatomy and Physiology Reading Outline - Module 2

Textbook readings:

Introduction of Bacterial Anatomy Mullins: Chapter 21, Pages 278-290

Morphology 279-281 Cell Wall and Membrane Structures 281-282 Motility 282-284 Endospores 284-286 Microscopy and Staining 287-288

Bacterial Physiology Mullins: Chapter 22, Pages 291-298

Nutrients 292-293 Oxygen 293 Water 293-294 Temperature 294 pH 295 Light 295 Osmotic Pressure 295-296 Interspecies Relationships 296-297

ANATOMY OF BACTERIA, Chapter 21, Pages 278 – 289

1. Binary Fission (page 279)

A. 20 minutes (a typical “Generation Time”. The Generation time is the amount of time it takes a cell to divide from one cell to two cells) Illustration at right demonstrates bacterial cell number After 24 hours if the generation time is 30 minutes.

0 10.5 21.0 41.5 82.0 162.5 323.0 643.5 1284.0 2564.5 5125.0 1,0245.5 2,0486.0 4,0966.5 8,1927.0 16,3847.5 32,7688.0 65,5368.5 131,0729.0 262,1449.5 524,28810.0 1,048,57610.5 2,097,15211.0 4,194,30411.5 8,388,60812.0 16,777,21612.5 33,554,43213.0 67,108,86413.5 134,217,72814.0 268,435,45614.5 536,870,91215.0 1,073,741,82415.5 2,147,483,64816.0 4,294,967,29616.5 8,589,934,59217.0 17,179,869,18417.5 34,359,738,36818.0 68,719,476,73618.5 137,438,953,47219.0 274,877,906,94419.5 549,755,813,88820.0 1,099,511,627,77620.5 2,199,023,255,55221.0 4,398,046,511,10421.5 8,796,093,022,20822.0 17,592,186,044,41622.5 35,184,372,088,83223.0 70,368,744,177,66423.5 140,737,488,355,32824.0 281,474,976,710,656

BacterialGrowth Potential

(Generation Time = 30 min)(Growth after 24 hours)

Microbiology FS – Bacterial Anatomy and Physiology Reading Outline

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2. Morphology of Bacteria (Pages 279-281)

A. Coccus

i. Coccus

ii. Diplococci

a. Neisseria gonorrhea ( à Gonorrhea)

iii. Streptococci

a. Streptococcus pyogenes ( à Strep Throat)

iv. Staphylococci

a. Staphylococcus aureus ( à Skin Infections)

B. Bacillus

i. Bacillus

a. Bacillus anthracis ( à Anthrax)

ii. Streptobacilli

C. Spiral

i. Vibrios

a. Vibrio cholerae ( à Cholera)

ii. Spirillum

iii. Spirochetes

a. Axial Filament (also called an Endoflagella)

b. Treponema pallidum ( à Syphilis)

c. Borrelia burgdorferi (à Lyme Disease)

Coccus

Diplococcus

Streptococcus

Staphylococcus

Bacillus

Streptobacillus

Vibrio

Spirillum

Spirochete

Microbiology FS – Bacterial Anatomy and Physiology Reading Outline

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3. Cell Wall and Membrane (Pages 281-282)

A. Cellular Organization

i. Cell Membrane

a. Phospholipid Bilayer

i. Cell Wall

a. Resists Osmotic Pressure b. Exception: Mycoplasma pneumoniae

4. Cytoplasm (Pages 282)

A. Organelles

B. DNA

C. Plasmids

Cell Membrane - made of phospholip-ids, it controls what may pass into or out of a cell

Cell Wall - a semi-rigid structure that prevents bacteria from rupturing due to osmotic presure

Capsule (Glycocalyx) - carbohydrate structure that had adhesion function if more “organized” or rigid; or if “unorga-nized” it is referred to as a slime layer and as such resists host immune responses.

Cytoplasm - refers to fluids and contents within the cell

Chromosome - of bacteria is a loop of DNA

Plasmids - additional loops of DNA that provide auxillary funcitons to the bacteria. Are of importance due to some producting toxins or conferring resistance to the bacteria

Flagella - promotes motility.

Fimbriae - promote adhesion to surfaces

Pili - also may promote adhesion, but also promote the passage of DNA from on bacteria to another bacteria

Microbiology FS – Bacterial Anatomy and Physiology Reading Outline

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5. Capsule (Pages 282)

A. Glycocalyx

B. Unorganized Glycocalyx (Slime Layer)

i. Resist Engulfment by Immune System

• Streptococcus pneumoniae ( à Pneumonia)

ii. Adhesion to mucous membrane

• Klebsiella pneumoniae ( à Pneumonia)

C. Organized Glycocalyx (Rigid Layer - Capsule)

i. Adhesion to suitable surface

• Streptococcus mutans ( à Dental Cavities) Adheres to teeth.

6. Flagella (Pages 282 - 284)

A. Function of Flagella in Prokaryotic Cells

B. Divisions (see figure 21-5, page 284)

i. Monotrichous

ii. Amphitrichous

iii. Lophotrichous

iv. Peritrichous

7. Pili and Fimbriae (Page 284)

A. Adhesion Function of Fimbriae

• Example: Neisseria gonorrhoeae

B. Pili Function - DNA transmission

Image Support: See Flagellar Arrangements

Image Support: Bacterial Cell Structure

Monotrichous

Lophotrichous

Amphitrichous

Peritrichous

Microbiology FS – Bacterial Anatomy and Physiology Reading Outline

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8. Endospores (Pages 284-286)

A. What is an endospore

B. ** See Endospore Handout

• Germination

C. Sporulation

D. Endospore resistance

E. Examples of endospore producers

• Bacillus anthracis ( à Anthrax)

• Clostridium tetani ( à Tetanus)

• Clostridium botulinum ( à Botulism)

• Clostridium perfringens ( à Gas gangrene)

F. Importance to Embalmers (Page 286)

9. Microscopy and Staining (Pages 287-289)

A. Gram Stain (Page 288 – 289)

• Gram Positive and Gram Negative Bacteria

PHYSIOLOGY OF BACTERIA, Chapter 22, Pages 291 – 297

10. Nutrition Requirements of Bacteria (Pages 291-293)

A. Autotrophic

B. Heterotrophic

• Example: Pseudomonas sp.

i. Saprophytes

ii. Facultative Bacteria

EnvironmentalStress

Sporulation during

induces Germination

FavorableEnvironmental

Conditions

Endospore

“Vegetative Bacterium”

Microbiology FS – Bacterial Anatomy and Physiology Reading Outline

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11. Oxygen Requirements of Bacteria (Page 293)

A. Obligate Aerobes

(note your text incorrectly identifies E. coli as an obligate aerobe. E. coli

is a facultative anaerobe)

• Pseudomonas sp. – is a particularly important concern for burn victims.

B. Obligate anaerobes

• Clostridium botulinum causes botulism

• Clostridium perfringens saprophytic regarding nonliving tissue

C. Microaerophilic

• Neisseria meningitidis causes meningococcal meningitis

D. Aerotolerant

• Streptococcus pyogenes causes strep throat, scarlet fever, etc.

Heavy Growth

Moderate Growth

Poor/No Growth

ObligateAerobes

ObligateAnaerobes

FacultativeAnaerobes

AerotolerantMicro-Aerophilic

Modified from Microbiology, 9th editionby Tortora, Funkd, and ‘’case

Very High Oxygen Concentration

Moderately High Oxygen Concentration

Moderate Oxygen Concentration

Low Oxygen Concentration

Very Low Oxygen Concentration

No Oxygen

This Illustration will beReviewed in Lecutre

Microbiology FS – Bacterial Anatomy and Physiology Reading Outline

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12. Moisture Requirements of Bacteria (Page 293 -294)

A. Generalization: Bacterial vs Fungal Diseases

13. Temperature Requirements of Bacteria (Page 294)

A. Psychrophiles

B. Mesophiles

C. Thermophiles

OptimumGrowth

TemperatureMinimum

GrowthTemperature

MaximumGrowth

Temperature

NoGrowth

NoGrowth

IncreasingStress

IncreasingStress

GrowthRate

Effect of variations in physiological variables. Examples of such variables are Temperature (shown here) but alsopH, osmotic pressures, oxygen concentrations etc etc.

A General Growth Curve

Psychrophiles0°C - 25°C

Mesophiles25°C - 40°C

Thermophiles40°C-104°C

Temperature as a Physiological Variable

GrowthPotential / Rate

0°C 110°C

This Illustration will beReviewed in Lecutre

Microbiology FS – Bacterial Anatomy and Physiology Reading Outline

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14. pH Requirements of Bacteria (Page 295)

A. Hydrogen Concentration

B. Helicobacter pylori

15. Osmotic Pressure (Page 295 - 296)

A. Osmotic Pressure and salt, sugar etc.

B. Embalming Fluid

1 2 3 4 5 6 7 8 9 10 11 12 13 14

Neutral

Skin Blood BleachAmmoniaStomach

Increasing Acidity(Hydrogen Ion Concentration Increases

(Hydroxyl Ion Concentration Decreases)

(Hydrogen Ion Concentration Decreases(Hydroxyl Ion Concentration Increases)

Increasing Alkalinity