Midterm 1 Flashcards
Goals of molecular typing
- identify the MICROBIAL CAUSE of disease
- identify RELATIONSHIPS between Bacteria
- identify how population of bacteria change with changing conditions
Uses of 16S rDNA Sequencing
❤types of microbes present( single or multiple species)
❤compare strains of bacteria-in an outbreak can be used to determine how isolated relate to one another
❤study complex microbial populations-in a microbial community can determine what species are present and how they change under certain conditions.
Infection
Colonization of the body by a bacterium CAPABLE of causing ⚡️⚡️DISEASE⚡️⚡️⚡️
Disease
Infection that produces 💥💥💥💥💥💥SYMPTOMES💥💥💥
Colonization
Bacterium OCCUPIES and MULTIPLIES in a particular area of the body.
This is our microbiota
A symptomatic carrier
An INFECTED person who does not have symptoms
Symptoms
Effects of bacterial infection apparent in an infected individual
Virulence/pathogenicity
Ability of a bacterium to cause disease
Virulence factors
Bacterial PRODUCTS or STRATEGIES that contribute to virulence/pathogenicity
Opportunist
Bacteria that normally do not cause disease in healthy people but can cause disease in people with impaired defences
Pathogen
An ORGANISM with a reputation of causing infectious disease
New disease caused by newly identified bacterial species
Legionnaire’s disease
Lyme disease
Old disease that were thought to be under control
Tuberculosis
MRSA
Old disease that are now know to have bacterial causes
Gastric ulcers and
Helicobacter pylori
Old disease with known causes that are getting more attention from the public and media
Gonorrhea
Chlamydia trachomatis
Periodontal disease
Porphyromonas gingivalis
Atherosclerosis
Chlamydophila pneumonia
An example of a bacteria that uses INVASION as a way to evade the host immune response
AND
Can escape the phagosome and live in the cytoplasm of phagocytic cells
Listeria Monocytogenes
2 bacteria that inhibit phagosome-lysosome fusion
Legionella
M. tuberculosis
Some bacteria change their surface antigens to keep one step ahead of the antibody response
Gonococci
Cause of Buruli ulcer
Mycobacterium ulcerans
—-passed by plasmid
An exotoxin not part of the bacterial genome passed by bacteriophage
Diphtheria toxin
An exotoxin not part of the bacterial genome passed by plasmid
Type G botulinum toxin
Who releases lecithinase
Which is a phospholipase that hydrolyzes the lipid lecithin in cell membrane
Clostridium perfringens
Who releases botulinum toxin
Clostridium botulinum
Toxic shock shock syndrome toxin-1
Staphylococcus aureus
This bacteria also has an alpha toxin which is a pore forming toxin
Streptococcal superantigen
Streptococcus pyrogens
Causes Lyme disease
Borrelia burdorferi
This one used manganese instead of iron
Gonocci
❤❤Adds sialic acid to its LPS to prevent C3 convertase formation
❤❤ some bacteria change their surface antigens to keep one step ahead of the antibody response
What bacteria inhibit phagosome-lysosome fusion
Legionella
M. Tuberculosis
What bacteria escapes the phagosome and lived in the cytoplasm of phagocytic cells
Listeria monocytogenes
Whah bacteria cannot be cultivated? It is the causative agent of syphilis
Treponema pallidum
Kochs #1 postulate
Bacteria must be associated with symptomes and present at the site of infection
Limitations of organ culture
❤They don’t last very long in vitro, they cannot be split & maintained
❤they don’t have intact circulation & lymphatic supply to take the immune response into account
Molecular kochs Postulate
1: the gene or its product should only be found in strains of bacteria that cause disease.
Limitation: virulence is multifactorial
Steps in IVET
1) creat plasmids in E.coli that have Salmonella sequences upstream of promoterless purA/lacZ genes
Septic shock symptoms
Vs
Toxic shock
Septic shock 💥hypotension 💥DIC 💥internal hemorrhages Causes by too much bacteria in our system --------------------------------------------- Toxic shock 💥 fever 💥 malaise 💥nausea 💥 vomiting
