Mycoplasma Flashcards
Nickname of Mycoplasma
Pleuropneumonia-Like Organisms = PPLO
Morphology of Mycoplasma
1. ____________ shape because of lack of _____ _________
2. An __________-dense core
3. Terminal _______/____ at one end for:
1. ________/_______ onto host cell
surface receptors
2. ______ motility
3. cell _______
Pleomorphic, cell wall, electron, organelle, disc, adherence, attachment, gliding, division
- What bacterium is pictured here?
- What is the arrow pointing to?
- Mycoplasma
- an electron-dense core terminal organelle/disc
- What bacterium is pictured here?
- What is the arrow pointing to?
- Mycoplasma
- an electron-dense core terminal organelle/disc
other image
- Describe the cell structure of Mycoplasma
- What drugs won’t work as a result of these structures?
- no cell wall, so beta-lactams R won’t work
- no flagella,
- no fimbriae,
- no lipopolysaccharide so polymixins/colistin R won’t work
“Christine Will Fuck For Lavashak”
Describe the toxins Mycoplasma possesses
- no/rare toxins,
- no/rare cytolysins,
- no/rare invasins
- Describe the Enzymes Mycoplasma uses?
- What drugs won’t work as a result of these structures?
- no/rare catalase
- no/rare superoxide dismutase
- no tricarboxylic acid cycle, no quinones, no cytochromes = reduced capacities for ATP synthesis
- no folic acid synthesis so Sulfa/trimethoprim R won’t work
- RNA polymerase gene, prone to mutation. rifampin R won’t work
naturally RNA poly is multidrug resistant
CRRFT
The cell surface of Mycoplasma is coated with?
- glycolipids –> antigen mimicry (authoimmunity)
- Lipoglycans –> antigen mimicry (authoimmunity)
- lipoprotein –> Switch ON/OFF regularly & changes its coat
- capsular polysaccharide,
- host-derived cholesterol,
- adhesins. …………………………………………..for attachment to diverse host epithelial cells and compounds
Mycoplasma secretes?
- hydrogen peroxide –> kill host cells by oxidizing their lipids, proteins, DNA, RNA by free radicals
- superoxide (O2–) –> kill host cells by oxidizing their lipids, proteins, DNA, RNA by free radicals
- nuclease –> degrade host nucleic acids
- immunoglobulin proteases –> degrade proteins including antibodies
- antioxidant enzymes –> detoxify free radicals
- sialidases –> degrade mucus
- hyaluronidases –> degrade hyaluronate
“HHIASSIN” aka “Hiya, sin!”
What Culture media & growth is needed for Mycoplasma?
- Highly fastidious
- Slow grower
Mycoplasma are ______ (i.e. difficult to _____) and therefore require ______ nutrient media that
includes Mycoplasma agar containing:
1. _______ _____ infusion
2. ________
3. 5% _____ autolysate
4. ________ ______ precursors
5. _______ (200 IU/ml) –> ?
6. _________ ______ (0.125 mg/ml)
7. 20% _______ or ______ serum…
fastidious, isolate, complex, beef heart, peptone, yeast, Nucleic acid, penicillin, thallium acetate, equine, human
- To prevent gram-positive
- To prevent gram-negative
- Serum provides cholesterol, amino acids &
fatty acids for synthesis of its cell membrane since they cannot produce them
On culture media, Mycoplasma is ______ growing (__-__ _____ of incubation) before colonies are apparent on agar which is what contributes to them causing _______ diseases.
slow, 1-2 weeks, chronic
Mycoplasma possess a unique ______ motility using _______ dense core. Have a “______ ______” appearance on agar media.
gliding, electron fried egg
M. mycoides subsp. mycoides, affects ________ and is a ______ colony
cattle, small
M. mycoides subsp. mycoides, affects _______ and is a _______ colony.
goat, large
List and explain the virulence factors of Mycoplasma
- Its cell surface molecules
a. Antigenic variation = which protein is responsible? Lipoprotein
b. Antigenic mimicry = which protein is responsible? lipoglycans and glycolipids - Secreted enzymes
- Its ability to manipulate host cells, internalization, and host genome
- Its ability to live inside and outside host cells to compete for nutrients (parasitism)
What organism is pictured here?
Mycoplasma
List the virulence factors of Mycoplasma
- Biofilms
- Capsule
- Adhesins
- Enzymes
- Toxins (free radicals)
- Antigenic variability
- Antigens mimicry (glycolipid)
- Incorporation of host antigens into Mycoplasma (i.e. capping)
- Intracellular life
Mycoplasma’s capsule contains?
Polysaccharides
What enzymes does Mycoplasma produce?
- Lipase
- Nuclease
- Ig protease
- Sialidase & hyaluronidase
- Antioxidant enzymes
NAILS
Antioxidant enzymes function to ensure bacterial ___________. The antioxidant enzymes that Mycoplasma produces are:
- __________ sulfoxide reductase
- organic ________ reductase
- osmotically inducible ___________ ____.
- ___________ dismutase
- ________
- ___________ reductase,
- _______ peroxidase,
- ______________
survival
methionine, hydroperoxide, protein C, superoxide, catalase, thioredoxin, thiol, peroxiredoxin
What toxins (free radicals) does Mycoplasma produce?
- H2O2
- O2-
- Community- acquired
respiratory distress syndrome toxin
What provides Mycoplasma with antigenic variability?
Lipoprotein