What is the bacterial structure that is a potent activator of innate host response?
LPS
What is the antiphagocytic bacterial structure?
Capsule
What kind of peptidoglycan have a Gram-Positive bacteria?
Thick and Layered
What is the common biochemical pathway for the pyruvate in the bacteria without oxygen?
Fermentation, pyruvate reduced to lactic acid by lactate dehydrogenase, regenerating NAD+ in the process.
What structure is a protection of colony from environmental, antimicrobials, and host response?
Biofilm
Which virulence mechanisms attach the bacteria to the host?
Adhesions
Which mechanisms of virulence occurs when the bacterium enters the host?
Invasions
Which bacterial products are that harm tissue or destroyed biological activities?
Endotoxins, but products depend on the bacteria (Exotoxins)
Which mechanisms of antibiotic action interference with bacterial cell wall?
Many of them inhibit peptidoglycan formation of layers or its synthesis completely
Which mechanisms of antibiotic action stop the protein production?
1. Prevent release of peptide chains, elongation, initiation and binding in 30s ribosome
2. Prevent initiation of synthesis and elongation in 50s ribosome
Which mechanisms of antibiotic action stop the genetic material production?
- Bind subunit of DNA gyrase
- Prevent transcription by binding RNA polymerase
- Disrupts bacteria DNA
Which mechanisms of antibiotic action stops the bacterial production of what it needs?
- Inhibits dihydropteroate synthase & reductase
- Disrupts folic acid synthesis
(Sulfonamides, Dapsone, Trimethoprim)
Which bacteria can act in different tissues?
S. aureus
Which bacteria has factors that need to be internalized into the host to become activated?
B. anthracis
Which bacteria comes to present as a symptom cough and sometimes with blood?
m. tuberculosis???
Which bacteria can’t be cultured on artificial media?
Mycobacterium Leprae
Which bacteria have a very specific shape that you can recognize in the microscope?
v. cholerae???
Which bacteria can produce abortion and diphteria?
Corynebacterium diphtheriae
Which bacteria uses holey's agar to detection?
Listeria and Related Gram-Positive Bacteria
Which bacteria can produce Gonorrhea?
Neisseria gonorrhoeae
Which bacteria has capsular polysaccharides?
Haemphilus (5 types, influenzae, aegyptius, ducreyl, actinomycetemcomitans, multocida)
Which virulence factors are associated with Enterobacteriaceae family?
Endotoxin, Capsule, Antigenic phase, Type 3 secretions, Sequestration of growth factors, Resistance to serum killing, and Antimicrobial resistance. LPS
E. coli --> Adhesions & Exotoxins.
Which bacteria is confirmed with TCBS agar?
Vibrio cholerae
Which bacteria is the most common opportunistic?
Anaerobic, Non-spore-forming, Gram-positive rods
ex. Lactobacillus spp. & Bifidobacterium spp.
Which bacteria produces Pertussis?
Bordetella pertussis
Which bacteria produces Brucellosis?
Brucella
Which bacteria produces Tularemia?
francisella tularensis???
Which bacteria produces Syphillis?
Treponema pallidum
Which bacteria produces Botulism?
Clostridium botulinum
Which bacteria is anaerobic and although it is part of commercial
probiotics for children and is
considered good for health, it
can cause diseases if it is found in places such as the heart?
lactobacillus???
Which bacteria produces Lyme disease?
Spirochaetaceae BORRELIA???
Which bacteria doesn’t have cell wall?
MYCOPLASMA
Are edema factor and lethal factor toxic by themselves?
NO??
What is the main property in isolated culture of Clostridium perfringens?
Form endospores (gas production & double zone hemolysis)
Why do mycobacterial infections have to be treated with multiple drugs for 6 months or more?
Lipid rich cell wall makes it resistant to traditional common antibacterial antibiotics. It is slowly growing.
What virulence factors have been associated with Neisseriaceae family?
- Pilin
- Por
- Opa
- Rmp
- LOS
- IgA1
- Beta-Lactamase
- transferrin- / lactoferrin- / hemoglobin- binding proteins
What are the most common virulence factors?
Capsule, adhesions, invasion
Which bacteria produces Gastritis?
Helicobacter pylori
Which bacteria is an obligatory intracellular parasite?
Chlamydia, or Chlamydiaceae
Which bacteria produces Rocky Mountain fever?
Rickettsia rickettsii
1546 Fracastoro
Early version of Germ Theory
1665 Hooke
Observes cork cells under microscope
1674 Van Leeuwenhoek
Observes single celled organisms
1847 Semmelweis
Hand washing reduces puerperal infections
1854 Snow
cholera bacteria transmitted in contaminated water
1856 Pasteur
discovers microbial fermentation while studying beer/wine
1862 Pasteur
DISPROVES spontaneous generation with swan neck flask
1867 Lister
begins using carbolic acid as a disinfectant during surgery
1876-1906 Koch
determined causative agents for many bacterial infections
- most common
- white light
- needs staining
- cell structures, tissues, and microorganisms
- limited contrast for transparent and unstained
- 40x-1000x
Brightfield Microscope
- uses condensor
- uses oblique light but its scattered
- background is dark
- no staining needed
- less effective with thick specimens
- 40x-1000x
Darkfield Microscope
- uses rings
- enhances contrast in transparent and unstained organisms
- produces high contrast images
- living cells, tissue cultures, and internal cell structures
- more complex and expensive
- 40x-1000x
Phase-Contrast Microscope
- use fluorescence to visualize specimens.
- Use high-intensity light, typically ultraviolet (UV), to excite fluorescent dyes
- form a brightly colored image against a dark background.
- for studying proteins, nucleic acids, and other biomolecules
- fluorescent dyes or genetically
encoded fluorophores; photobleaching and autofluorescence can
limit image quality and duration - Magnification: 40x to 1000x
Fluorescent Microscope
- Utilize an electron beam to illuminate the specimen, which allows for imaging at the nanometer scale
- Transmission Electron Microscopes (TEM) and Scanning Electron Microscopes (SEM)
- Used to view viruses, cell organelles, and
nanoparticles. - Extremely high resolution (up to atomic level)
- Expensive, large, and complex; requires vacuum environment and extensive sample preparation
- TEM- 1,000,000x or more SEM- 20x to 300,000x
Electron Microscope
ANAEROBICBACTERIA
What are the two agars?
What are the three main types? (Hint: B..., C..., A....)
How can you confirm?
Anaerobic culture (semisolidagar or Brucella agar)
Bacteroides
Clostridium
Actinomycetes
PCR
AEROBICBACTERIA
Wet mount and Gram stain (motility, shape, +/-)
What are the three shapes that able to be identified?
- Vibrio
- Spirillos
- Spiroquetas
How are Vibrios differentiated? What test is it? What are the three types?
TCBS test.
V. cholerae, V. parahaemolyticus, V. vulnificus
How are Spirilla and Speriquets differentiated? What are the three examples given? Hint: Syphillis & Fever, headache, bone pain & Tick or luose-borne relapsing fever.
Stain & Immunohistochemistry.
Treponema Pallidum, Leptospira interrongans, Borrelia recurrentis
What is the next step after determining they are aerobic bacteria, and it is none of the other shapes? From there what is determined?
GRAM STAIN. Positive or Negative. Cocci or Bacilli.
If you have a Gram-Positive Cocci, what test do you perform next? What results do you get from those tests? Are there any additional tests? What is the specific bacteria that is mentioned?
The CATALASE test.
Positive results in Staph. Additional test: COAGULASE test. Positive S. aureus, Negative others.
Negative results in Strep. Additional test HEMOLYSIS
If you have Gram-Positive Bacilli, what are the options? Hint: there are 4
Bacillus, Lactobacillus, Corynebacterium, Listeria
If you have Gram-Negative Cocci, what are the options? Hint: there are 3
Neisseria, Eikenella, Kingella
If you have Gram-Negative Bacilli, what tests need to be done? Hint: there are 7
- Catalase
- Oxidase
- Coagulase
- Sugar or TSI
- Indole
- Citrate
- Urease
Lactose Test (Mac Conkey agar) - positive? negative?
Positive Pink. Negative Yellow.
Citrate Test - positive? negative?
Positive Blue. Negative Green.
Indole - positive? negative?
Positive Pink. Negative Yellow.
Urease Test -positive? negative?
Positive Pink. Negative Yellow.