Module 1: Microbiology, Introduction to Microbiology
➔ The players
Immunology & Infectious Disease ① What is microbiology?
For all of microbiology… Microbiology = the study of microscopic living
1. Investigate: things (most life)
- How micro-organisms invade & establish infect • Bacteria:
in the body - Primitive/prokaryotic simple cells
- How infection can be prevented/ treated - Without a membrane bound nuclei
- Has circular DNA in cytoplasm.
2. Explain:
- The role of inflammation & the immune system
• Fungi:
in specific & non-specific mechanisms of body
- Eukaryotic cells (animal cell structure)
defense (Incl. their role in disease resistance)
- Spore forming (asexual
reproductive cell)
3. Describe:
- Unicellular forms (yeasts)
- Epidemiology, pathology, treatment, & methods
- Multicellular forms (moulds)
of limiting spread of main groups of
- Uni & Multicellular forms of fungi = dimorphic
microorganisms & parasites affecting humans
fungi.
1: Introduction to Microbiology • Parasites:
1. How does microbiology relate to our - Not a ‘taxonomy’ instead it described a
region? – PNG relationship “parasitic relationship”
a. Why is DR-TB (drug resistant tuberculosis) - 1 harms host, (1+..1-)
endemic in PNG & not Australia? - E.g., Helminths, Protozoa
b. Why are case-fatality rates of melioidosis so - Some large - eggs, microscopic still
high in regional endemic areas? - Some small
c. Why rheumatic heart disease in indigenous
communities? • Viruses:
- Very small & simple
2. COVID-19 - Abiotic (non-living), completely dependent on
- Why is it a pandemic? host
- Lockdown vs herd immunity - Change genetic material of host.
- How & why is it pathogenic?
- Vaccines/immunity issues • Prions:
- Is a protein
PNG & Microbiology - Causes protein infection (misfolded protein)
➔ What is the problem? - Molecule/compound NOT infectious particle
- Drug resistant tuberculosis (DR-TB) – endemic in
PNG Responsible for CJD or “kuru”– Creutzfeldt-Jakob
- ↓ access to appropriate healthcare disease = subacute spongiform encephalitis
- Indigenous community = more susceptible & Also causes mad cow disease
vulnerable to same diseases
• BM1011 TERM Property TOPIC TITLE → subtopic ① ② ③ ④ ⑤ ⑥ ⑦ ⑧ ⑨ ↓ ↑ ∴ + = ≈ Mnemonic
, ➔ What is the significance of microbes?
Microbes are ubiquitous
- More in/on our body than our own cells
- Symbiotic relationship btwn. us & them.
Essential in Ecology
- Food production (beer, wine, cheese…)
- Waste management
- Health
Can be pathogenic → our concern
- Prevention
- Management
- Treatment
- Diagnosis of patients with infectious disease Classification of Bacteria
- Directly involved with (infection control,
community medicine, public education) ② How are bacteria & viruses classified?
➔ Linnaean model of classification
➔ Challenges in today’s world
Antibiotic resistance: MRSA, VRE 7 major levels: based on morphological &
physiological characteristics
New emerging patterns: HIV, BLV (cattle), 1. Kingdom
melioidosis, SARSV, H7N9, Sars-cov-2 (COVID) 2. Phylum
3. Class
Old re-emerging patterns: MDR/XDR-TB 4. Order
5. Family
Developing world/ social determinants of health 6. Genus
7. Species
2: Bacteria & Viruses Sometimes sub-/super- levels introduced for
1: Bacteria convenience.
① Structure of bacteria
➔ Naming microbes
a. Main features & unique characteristics
1. Genus names first starting with high case
b. Clinical significance of main features
letter
2. Followed by species names with lower
• Bacteria
case
- Simple, no-defined nucleus, small (1-5um)
- Free-living (mostly), absorb nutrients from the Underline (if handwriting, Italics if word
environment. processor
- Reproduce rapidly via binary fission (1-
Names are
1,000,000 in 6-7 hrs)
either
memorial or a
description
• BM1011 TERM Property TOPIC TITLE → subtopic ① ② ③ ④ ⑤ ⑥ ⑦ ⑧ ⑨ ↓ ↑ ∴ + = ≈ Mnemonic
,➔ Bacterial Classification ➔ Gram stain tells you 4 possible things
Classification criteria of bacteria ①B Clinical significance of the features of
bacteria
1. Cell wall composition (staining
Fundamental
characteristics) What does gram stain tell you?
criteria ①A
2. Shape (morphology) 1. Cell wall composition of bacteria (2 options)
→ clinical significance of bacteria’s main
---- > (Determined by gram stain)
features
3. Physiology (temp, pH, oxygen requirements) a. Antibiotic target:
4. How they utilise various substrates for energy Lots of peptidoglycan ∴ lots of target →
antibiotic kills cell wall more efficiently
5. Pathogenicity
E.g., penicillin ∴ Red stain = penicillin resistant
6. Habitat
Lots of lipid - difficult for antibiotic to get in
Which are determined by the Gram stain
(more resistant to antibiotics)
Gram stains - Lipid acts as endotoxin
Gram positive: Blue Characteristics
LPS (lipopolysaccharide) in cell wall. If antibiotic
Thick releases endotoxic lipid into blood stream by
peptidoglycan liberating bacterial cell = septic shock
∴ important to have correct antibiotic
S-layer proteins
Teichoic acid 2. Its shape (2 options)
4. Round (cocci)
5. Rod shape (bacilli)
Be aware that a few variations exist
E.g., Spirilla (corkscrew)
Gram negative: Red ➔ Endotoxic shock (sepsis)
Characteristics • Endotoxin: toxin in a bacterial cell wall
that is released when the cell wall
Thin disintegrates & is harmful to the body
peptidoglycan
with LPS • Endotoxic shock (sepsis): a huge
Lipid layer is inflammatory response that can lead to organ
barrier to many failure.
antibiotics Septic shock → most severe form of sepsis
(penicillin) causing low blood pressure & thus damage to
multiple organs.
LPS = lipopolysaccharides
• BM1011 TERM Property TOPIC TITLE → subtopic ① ② ③ ④ ⑤ ⑥ ⑦ ⑧ ⑨ ↓ ↑ ∴ + = ≈ Mnemonic
, Different Bacteria - Gram Stains Adherence & Genetic transfer
Gram positive cocci (blue stained, round) • Pill/ Fimbriae: adherence,
genetic transfer. Long
E.g., Staphylococcus
filamentous protein
aureus
structure @ the surface of cells.
Environmental resistance
Gram positive bacilli (blue stained, rod shaped)
• Endospore: bacteria produce this - a
E.g., Clostridium tough, dormant (non-reproductive) outer
perfringens layer that allow the cells to be highly
resistant to environmental stress &
preserves the genetic material of the cell
Gram negative cocci (red (survival mechanism)
stained, round)
E.g., Neisseria meningitides
Gram negative cocci (red
stained, round)
E.g., Escherichia coli
Diseases caused by bacteria
The exception of gram-negative bacteria:
③ What diseases are associated with bacterial
Gram negative spirochetes (red stained, spiral) infection?
E.g., Treponema palladium ➔ Primary vs Secondary Bacterial Infections
- Gram negative cell wall
• Primary infection: initial infection of a
- Doesn’t stain well (too
host by a pathogen that has completed
narrow) – use different stain
the incubation (dormant) period.
• Secondary infection: occurs when a
External structures of bacteria
primary infection has caused a person to
➔ Structure used to enhance virulence be more susceptible to disease, resulting
in another (secondary) infection.
• Virulence: the ability of an organism to
infect the host & cause disease. ➔ Spirochetes
Motility Syphilis
• Flagella: means of motility. Caused by spirochetes
Microscopic hair-like structures (Treponema
involved in locomotion. pallidum).
Antiphagocytic Portal of entry:
Urogenital.
• Capsule: antiphagocytic, stops
white blood cells killing it
• BM1011 TERM Property TOPIC TITLE → subtopic ① ② ③ ④ ⑤ ⑥ ⑦ ⑧ ⑨ ↓ ↑ ∴ + = ≈ Mnemonic
➔ The players
Immunology & Infectious Disease ① What is microbiology?
For all of microbiology… Microbiology = the study of microscopic living
1. Investigate: things (most life)
- How micro-organisms invade & establish infect • Bacteria:
in the body - Primitive/prokaryotic simple cells
- How infection can be prevented/ treated - Without a membrane bound nuclei
- Has circular DNA in cytoplasm.
2. Explain:
- The role of inflammation & the immune system
• Fungi:
in specific & non-specific mechanisms of body
- Eukaryotic cells (animal cell structure)
defense (Incl. their role in disease resistance)
- Spore forming (asexual
reproductive cell)
3. Describe:
- Unicellular forms (yeasts)
- Epidemiology, pathology, treatment, & methods
- Multicellular forms (moulds)
of limiting spread of main groups of
- Uni & Multicellular forms of fungi = dimorphic
microorganisms & parasites affecting humans
fungi.
1: Introduction to Microbiology • Parasites:
1. How does microbiology relate to our - Not a ‘taxonomy’ instead it described a
region? – PNG relationship “parasitic relationship”
a. Why is DR-TB (drug resistant tuberculosis) - 1 harms host, (1+..1-)
endemic in PNG & not Australia? - E.g., Helminths, Protozoa
b. Why are case-fatality rates of melioidosis so - Some large - eggs, microscopic still
high in regional endemic areas? - Some small
c. Why rheumatic heart disease in indigenous
communities? • Viruses:
- Very small & simple
2. COVID-19 - Abiotic (non-living), completely dependent on
- Why is it a pandemic? host
- Lockdown vs herd immunity - Change genetic material of host.
- How & why is it pathogenic?
- Vaccines/immunity issues • Prions:
- Is a protein
PNG & Microbiology - Causes protein infection (misfolded protein)
➔ What is the problem? - Molecule/compound NOT infectious particle
- Drug resistant tuberculosis (DR-TB) – endemic in
PNG Responsible for CJD or “kuru”– Creutzfeldt-Jakob
- ↓ access to appropriate healthcare disease = subacute spongiform encephalitis
- Indigenous community = more susceptible & Also causes mad cow disease
vulnerable to same diseases
• BM1011 TERM Property TOPIC TITLE → subtopic ① ② ③ ④ ⑤ ⑥ ⑦ ⑧ ⑨ ↓ ↑ ∴ + = ≈ Mnemonic
, ➔ What is the significance of microbes?
Microbes are ubiquitous
- More in/on our body than our own cells
- Symbiotic relationship btwn. us & them.
Essential in Ecology
- Food production (beer, wine, cheese…)
- Waste management
- Health
Can be pathogenic → our concern
- Prevention
- Management
- Treatment
- Diagnosis of patients with infectious disease Classification of Bacteria
- Directly involved with (infection control,
community medicine, public education) ② How are bacteria & viruses classified?
➔ Linnaean model of classification
➔ Challenges in today’s world
Antibiotic resistance: MRSA, VRE 7 major levels: based on morphological &
physiological characteristics
New emerging patterns: HIV, BLV (cattle), 1. Kingdom
melioidosis, SARSV, H7N9, Sars-cov-2 (COVID) 2. Phylum
3. Class
Old re-emerging patterns: MDR/XDR-TB 4. Order
5. Family
Developing world/ social determinants of health 6. Genus
7. Species
2: Bacteria & Viruses Sometimes sub-/super- levels introduced for
1: Bacteria convenience.
① Structure of bacteria
➔ Naming microbes
a. Main features & unique characteristics
1. Genus names first starting with high case
b. Clinical significance of main features
letter
2. Followed by species names with lower
• Bacteria
case
- Simple, no-defined nucleus, small (1-5um)
- Free-living (mostly), absorb nutrients from the Underline (if handwriting, Italics if word
environment. processor
- Reproduce rapidly via binary fission (1-
Names are
1,000,000 in 6-7 hrs)
either
memorial or a
description
• BM1011 TERM Property TOPIC TITLE → subtopic ① ② ③ ④ ⑤ ⑥ ⑦ ⑧ ⑨ ↓ ↑ ∴ + = ≈ Mnemonic
,➔ Bacterial Classification ➔ Gram stain tells you 4 possible things
Classification criteria of bacteria ①B Clinical significance of the features of
bacteria
1. Cell wall composition (staining
Fundamental
characteristics) What does gram stain tell you?
criteria ①A
2. Shape (morphology) 1. Cell wall composition of bacteria (2 options)
→ clinical significance of bacteria’s main
---- > (Determined by gram stain)
features
3. Physiology (temp, pH, oxygen requirements) a. Antibiotic target:
4. How they utilise various substrates for energy Lots of peptidoglycan ∴ lots of target →
antibiotic kills cell wall more efficiently
5. Pathogenicity
E.g., penicillin ∴ Red stain = penicillin resistant
6. Habitat
Lots of lipid - difficult for antibiotic to get in
Which are determined by the Gram stain
(more resistant to antibiotics)
Gram stains - Lipid acts as endotoxin
Gram positive: Blue Characteristics
LPS (lipopolysaccharide) in cell wall. If antibiotic
Thick releases endotoxic lipid into blood stream by
peptidoglycan liberating bacterial cell = septic shock
∴ important to have correct antibiotic
S-layer proteins
Teichoic acid 2. Its shape (2 options)
4. Round (cocci)
5. Rod shape (bacilli)
Be aware that a few variations exist
E.g., Spirilla (corkscrew)
Gram negative: Red ➔ Endotoxic shock (sepsis)
Characteristics • Endotoxin: toxin in a bacterial cell wall
that is released when the cell wall
Thin disintegrates & is harmful to the body
peptidoglycan
with LPS • Endotoxic shock (sepsis): a huge
Lipid layer is inflammatory response that can lead to organ
barrier to many failure.
antibiotics Septic shock → most severe form of sepsis
(penicillin) causing low blood pressure & thus damage to
multiple organs.
LPS = lipopolysaccharides
• BM1011 TERM Property TOPIC TITLE → subtopic ① ② ③ ④ ⑤ ⑥ ⑦ ⑧ ⑨ ↓ ↑ ∴ + = ≈ Mnemonic
, Different Bacteria - Gram Stains Adherence & Genetic transfer
Gram positive cocci (blue stained, round) • Pill/ Fimbriae: adherence,
genetic transfer. Long
E.g., Staphylococcus
filamentous protein
aureus
structure @ the surface of cells.
Environmental resistance
Gram positive bacilli (blue stained, rod shaped)
• Endospore: bacteria produce this - a
E.g., Clostridium tough, dormant (non-reproductive) outer
perfringens layer that allow the cells to be highly
resistant to environmental stress &
preserves the genetic material of the cell
Gram negative cocci (red (survival mechanism)
stained, round)
E.g., Neisseria meningitides
Gram negative cocci (red
stained, round)
E.g., Escherichia coli
Diseases caused by bacteria
The exception of gram-negative bacteria:
③ What diseases are associated with bacterial
Gram negative spirochetes (red stained, spiral) infection?
E.g., Treponema palladium ➔ Primary vs Secondary Bacterial Infections
- Gram negative cell wall
• Primary infection: initial infection of a
- Doesn’t stain well (too
host by a pathogen that has completed
narrow) – use different stain
the incubation (dormant) period.
• Secondary infection: occurs when a
External structures of bacteria
primary infection has caused a person to
➔ Structure used to enhance virulence be more susceptible to disease, resulting
in another (secondary) infection.
• Virulence: the ability of an organism to
infect the host & cause disease. ➔ Spirochetes
Motility Syphilis
• Flagella: means of motility. Caused by spirochetes
Microscopic hair-like structures (Treponema
involved in locomotion. pallidum).
Antiphagocytic Portal of entry:
Urogenital.
• Capsule: antiphagocytic, stops
white blood cells killing it
• BM1011 TERM Property TOPIC TITLE → subtopic ① ② ③ ④ ⑤ ⑥ ⑦ ⑧ ⑨ ↓ ↑ ∴ + = ≈ Mnemonic
