Concept Map

Created by Lauren Blaes

Enterotoxin

Subset of exotoxin that specifically affects the small intestine.

Helper T-Cell

Helper T-cells play a crucial role in activating other immune cells

B-Cell

The B-cells will secrete lots of antibodies that will then disseminate throughout the body, including to the original site of infection to help control the infection

Bacteriophage

*Viruses that infect bacteria

Exotoxin

A toxin that is secreted form the cell

Cells of the Immune System (L16)

Antibodies

Protein produced by B cells to neutralize pathogens (bacteria and viruses) and pathogen proteins (toxins).

Virus Structure

Immunity

Immunity: ability to ward off disease
Susceptibility: lack of resistance to a disease

Toxin

A biologically produced poison that aids in pathogenicity.

Epitope

An epitope is the specific molecular

structure on an antigen that an

immune cell receptor binds and

responds to.

Damage to Host

Immune Response

Antigen (L17)

An antigen molecule capable of inducing an immune response. A molecule that our immune system can detect as foreign (non-self)

Psychrophile

low temperatures

Mesophile (Streptococcus)

midrange temperature around 37 degrees celcius (thrives in human body temperature)

Virus (L15)

genetic element that cannot replicate independently of a living (host) cell.

Glycolysis

Energy Yield = 2 ATP/glucose

- Breaks down glucose to pyruvate

Thermophile

high temperature

Colonization (colonize the throat, skin, or nasopharynx w/o causing disease)

When a microorangism is established and growing in a host, but not harming the host.

Target Alteration/Mutation

-Mutation that results in change in host protein

structure where the antibiotic is no longer able

to interact with its target.

-Mutation can be as little as one

base/nucleotide change resulting in a different

amino acid (missense mutation)

Membrane Impermeability

Some antibiotics are too bulky, or are highly charged, inhibiting them from crossing the cell membrane or outer membrane.

Temperature

Hyperthermophile

very high temperature

Pathogen (Streptococcus)

Microbial parasite that causes disease (damage to host)

Oxygen

Mechanisms of Antibiotic Resistance

Antibiotic Efflux

Protein pumps that export antibiotics out of the cell.
The antibiotic enters the cell but will be pumped out before acting upon its target

Fermentation (Since Streptococcus lacks ETC) (L8)

NAD+ is regenerated to continue glycloysis (NO OXIDATIVE PHOSPHORYLATION)

Metabolic Pathways (L7)

Unlike aerobic bacteria streptococcus does not use the electron transport chain and also lacks TCA/Krebs/Citric Acid Cycle

Growth Requirements (L5)

Obligate Aerobes

Require oxygen to grow

Infection (streptococcus actively grows in tissues, triggering an immune response)

When a microorganism penetrates host defenses to actively grow within a host and cause damage or impair host cell processes and functions.

Growth

Growth: Increase In the number of cells (not cell size).

Media/ Food and Nutrients

Streptococcus prefers a more acidic environment and can tolerate moderate salt concentrations but is not halophilic.

Obligate Anaerobes

Do not require oxygen, oxygen is toxic.

Host and Microbial Interactions (L14)

Disease (Strep Throat)

Damage or injury to the host that impairs host function.

Narrow Spectrum

Targets specific bacteria (e.g. gram + or gram -, but not both)

Antibiotic Inactivation

Antibiotic is inactivated by cellular enzymes.
beta-lactam Antibiotics: inhibit peptidoglycan cell wall synthesis
-Block amino acid crosslinking enzymes
β-lactamases hydrolyze the β-lactam ring

Facultative Anaerobe (Streptococcus)

Oxygen is not essential but can use it.

Microaerophiles

Require oxygen for respiration but at lower levels.

No Antibiotic

Negative regulation - polymerase binds

Binanary Fission (L4)

Asexual cell division, parent cell sprits into two. For cell division to occur pre-exisiting peptidoglycan needs to be cut for new sythesis.

Min Proteins

Ensures cell divison occurs at the middle of the cell.

Antibiotics (L18)

Kills or inhibits the growth of bacteria

+ Antibiotic

binds to promoter region → positive regulation

Microbiology Concept Map for Streptococcus

Cellular Division and Multiplication

Streptococcus is spread through respritory droplets (coughing and sneezing).

Lac Operon (L12)

glucose then lactose consumption

Broad Spectrum

Works against a wide range of bacteria (e.g. both Gram +/-)

FtsZ Protein

Makes a ring for division around the center of the cell.

Microbial Population Growth

Control of Microbial Growth

Swimming

Operon Regulation

Streptococcus regulates operons to express factors like toxins and immune evasion proteins.

Point Mutations

Immune detection

Robert Hooke

The first to describe microbes.

Fundamental and Introduction

Cell Structure and Function

Movement (L3)

Streptococcus attaches to the host cell using proteins in the membrane to propel itself.

Gliding

Transcriptional Regulation

Streptococcus uses transcriptional regulation to adapt to hosts environment.

Sterilization

Often confused with sterilization which is killing every living thing.

Twitching

Genetic Regulation

Mutations (L13)

Occurs spontaneously due to DNA replication erros → from antibiotics

Insertions/Deletions

Enhancing invasiveness

Development of the Microscope (L2)

Microscopy

Structure

Streptococcus Shape: Cocci or chains of cocci

Anton Van Leeuwenhoek

First to describe bacteria.

History of Microbiology

Bright Field

PROS: easy can see live cells

CONS: finite resolution : 0.2 mm

Electron Microscope

Uses electrons Instead of photons (visible light).

Cytoplasmic Membrane

Barrier that separates the Inside ofthe cell from the outside environment.

Microbial Genetics

Fanny Hesse

Solid Media, Designed and Developed Agar

Cytoplasm

Aqueous mixture of macromolecules, ions and ribosomes.

Petri Dishes Used

Serile Method for Experiments

Griffith's Experiment (L9)

Proved that cells transform. Strep is naturally competent: uptake DNA from environment and insert that DNA into own chromosome.

Replication (L11)

DNA reads 3'-5'
DNA makes 5'-3'
Leading strand is continuous
Lagging strand - okazaki fragments

Francesco Redi

Worked towards disproving theory of spontaneous generation.

Theory of Spontaneous Generation

Hypothesis that living organisms arise spontaneously from non-living matter.

Fluorescence Microscopy

Fluorescence: absorbs certain wavelength emits a different one

autofluorescence : naturally occuring

- example: Chlorophyll

artificial fluorescence: man made

- example: Stains and GFP

Cell Wall

Present in most microbes; confers structural strengths.

Chromosome

Single piece of the genome.

DNA

Chromosomes packaged into DNA.

Transcription

DNA → RNA (T → U)

Germ Theory of Disease

Pure Culture

One strain/species of one organism and nothing else (genetically Identical) - needed to isolate to prove why x does y.

Genome (L10)

All genetic information.

Translation

Initiation: small subunit binds to mRNA and finds AUG start codon
Elongation: another tRNA enters A-site
Termination: stop codon is recognized, translation is terminated

John Needham

Lazzaro Spallanzani

Robert Koch

Demonstrated link between microbes infectious diseases, and developed techniques for obtaining pure cultures of microbes.

Simple Stain

kills sell but can contrast better

Simple Stain (methylene blue)

Gram Negative

Purple stain and for Gram-negative cell wall: two layers - outer membrane & peptidoglycan.

Single Peptide Bond

Louis Pasteur

Disproved the theory of spontaneous generation.

Koch's Postulates (L1)

Koch's postulates were used to prove a specific organism is responsible for a specific disease.

Agar

Stains

kills sell but can contrast better

Pasteurization

Invented pasteurization. Pasteurization is decreasing microbial amount but not killing all.

Gram Positive (STREPTOCOCCUS)

Pink stain and for Gram-positive cell wall: one layer of peptidoglycan.

Amino Acid Interbridge

Vaccinology

Pasteur - Rabies Vaccine, lots of ethical issues though.

MacConkey Agar (Streptococcus - No Growth)

Selects for Gram Negative Bacteria
Does not allow growth of Gram-positive Bacteria

Peptidoglycan

composed of layers of Polysaccharides:

N-acetylglucosamine and N-acetylmuramicacid amino acids (NAG-NAM)

Methods of Assaying Microbial Growth (L6)

Edward Jenner

Pioneer of Vaccinology

Making Peptidoglycan

Transglycosylases: enzymes that form the beta (1,4) linkages btw NAG-NAM sugars

Transpeptidases: enzymes that form amino acids link between NAM Sugars of different layers.