BIO 420 Microbiology: Comprehensive Study Guide for Lecture and Laboratory Exams

Module 1: Foundations of Microbiology

Key Experiments and Microbial Classification

• Spontaneous Generation: Understand the experiments disproving spontaneous generation, especially Pasteur's experiment.

• Microbial Taxonomy: Compare and contrast Bacteria, Archaea, and Eukarya (including domain characteristics, cell structure, and chemical composition).

• Prokaryotic Cells: Identify cell components and their functions.

• Transport Systems: Explain prokaryotic transport systems, including facilitated diffusion, active transport, and group translocation.

• Cell Wall Structure: Differentiate between Gram-positive and Gram-negative cell walls. Discuss how cell wall structure affects susceptibility to antibiotics like penicillin and lysozyme.

Microbial Growth and Reproduction

• Binary Fission: Describe the process and its role in microbial population growth.

• Growth Curve: Stages of a growth curve in a closed system (lag, log, stationary, death).

• Environmental Factors: Requirements for temperature, oxygen, pH, and other factors in bacterial growth. Define terms such as psychrophile, mesophile, thermophile, and hyperthermophile.

• Control of Microbial Growth: Methods of sterilization, disinfection, and antisepsis. Compare and contrast physical and chemical methods.

Module 2: Microbial Genetics and Molecular Biology

DNA, RNA, and Protein Synthesis

• Structure and Function: Compare and contrast DNA and RNA.

• Transcription and Translation: Outline the process, focusing on the role of RNA polymerase, sigma factors, promoters, and terminators.

• Gene Expression: Explain the regulation of gene expression in prokaryotes (e.g., operons, inducers, repressors, CAP-cAMP complex).

• Mutations: Types of mutations and their effects on protein function.

• Horizontal Gene Transfer: Mechanisms such as transformation, transduction, and conjugation.

Module 3: Microbial Metabolism and Laboratory Techniques

Metabolic Pathways

• Catabolism and Anabolism: Distinguish between these processes and their roles in microbial metabolism.

• Enzyme Function: Describe enzyme structure, function, and regulation.

• Energy Production: Outline glycolysis, the Krebs cycle, and electron transport chain.

Laboratory Techniques

• Staining Techniques: Simple, negative, Gram, acid-fast, and endospore stains. For each, know the steps, purpose, and interpretation.

• Microscopy: Use and care of the microscope in microbiology labs.

Module 4: Microbial Immunology and Pathogenesis

Immunity and Immune Response

• Innate vs. Adaptive Immunity: Compare and contrast, with examples of key components (e.g., first line of defense, sensory system, effector components).

• Cells of the Immune System: Functions of phagocytes, lymphocytes, antigen-presenting cells, and others.

• Antibody Structure and Function: Classes of antibodies and their protective outcomes.

• Antigen Presentation: MHC class I and II pathways, T helper and cytotoxic T cell responses.

• Immunological Memory: Role of B and T memory cells.

Hypersensitivity and Immunization

• Types of Hypersensitivity: Mechanisms and clinical examples (Type I-IV).

• Vaccines: Types, mechanisms, and examples.

Module 5: Microbial Growth, Control, and Laboratory Applications

Growth Curve and Environmental Factors

• Growth Curve: Stages in a closed system and factors affecting growth (temperature, oxygen, pH, water availability).

• Microbial Control: Physical and chemical methods, including sterilization, disinfection, and antisepsis.

Laboratory Applications

• ELISA: Principle and application for detecting antigens or antibodies.

• Kirby Bauer Disk Diffusion Test: Principle, interpretation, and factors affecting results.

• Antibiotic Mechanisms: Mechanisms of action (cell wall synthesis, protein synthesis, nucleic acid synthesis, metabolic pathways).

• Antibiotic Resistance: Mechanisms and clinical significance.

• Selective and Differential Media: Purpose and interpretation.

• DNA Gel Electrophoresis: Principle, procedure, and applications in molecular biology.

Module 6: Pathogenesis and Infectious Diseases

Pathogen Identification and Disease Mechanisms

• Pathogenesis: Virulence factors, mechanisms of immune evasion, and disease progression.

• Transmission: Direct and indirect transmission, including vector-borne and zoonotic diseases.

• Signature Signs: Unique signs of infection for specific pathogens.

Major Pathogens by System

• Respiratory System: Streptococcus pyogenes, Streptococcus pneumoniae, Mycobacterium tuberculosis, Corynebacterium diphtheriae, Legionella pneumophila, Influenza virus, Severe Acute Respiratory Syndrome Coronavirus 2.

• Skin Infections: Staphylococcus aureus, Streptococcus pyogenes, Varicella-zoster virus, Measles virus, Rubella virus.

• Digestive System: Rotavirus, Norovirus, Mumps virus, Hepatitis viruses (A, B, C, D, E).

• Blood and Lymphatic System: Epstein-Barr virus, Yellow fever virus, Dengue viruses.

• Nervous System: Rabies virus, Poliovirus, West Nile virus, Herpes simplex virus.

• Reproductive and Urinary Tract Infections: Neisseria gonorrhoeae, Treponema pallidum, Herpes simplex virus, Human papillomavirus.

Tables

Table: Comparison of Innate and Adaptive Immunity

Feature	Innate Immunity	Adaptive Immunity
Response Time	Immediate (minutes to hours)	Delayed (days to weeks)
Specificity	Non-specific	Highly specific
Memory	No memory	Immunological memory present
Main Components	Physical barriers, phagocytes, complement	B and T lymphocytes, antibodies

Table: Mechanisms of Antibiotic Action

Antibiotic Class	Target	Example
Beta-lactams	Cell wall synthesis	Penicillin
Aminoglycosides	Protein synthesis (30S ribosome)	Streptomycin
Macrolides	Protein synthesis (50S ribosome)	Erythromycin
Quinolones	DNA gyrase (nucleic acid synthesis)	Ciprofloxacin

Key Equations and Formulas

• Growth Rate Equation:

$N_t = N_0 e^{ ext{kt}}$

• Where $N_t$ is the number of cells at time $t$, $N_0$ is the initial number of cells, and $k$ is the growth rate constant.

• Dilution Factor Equation:

$\text{Dilution Factor} = \frac{\text{Volume of Sample}}{\text{Total Volume}}$

• ELISA Standard Curve Equation:

$y = mx + b$

• Where $y$ is the absorbance, $m$ is the slope, $x$ is the concentration, and $b$ is the y-intercept.

Additional info:

• Some content was inferred and expanded for academic completeness, such as detailed explanations of laboratory techniques and immunological concepts.

• Pathogen lists and mechanisms were grouped by organ system for clarity.