Bacterial Anatomy and Physiology - Noel Ways FS/Lectures/02...Microbiology FS – Bacterial Anatomy...
Transcript of Bacterial Anatomy and Physiology - Noel Ways FS/Lectures/02...Microbiology FS – Bacterial Anatomy...
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