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Flashcards in bacteria: part 2 Deck (20)
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Normal 3 tpes of naceria

Cocci, bacilli, spiral


How does flagella and pili contribute to virulence

Flagella (movement, attachment) Pili (important adherence factors)


How does biofilms contribute to virulence. Examples

(organized agregrates of bacteria embedded in polysaccahride matricesi. e. Pseudomonas aeruginosa i.e. Staphylococcus epidermidis


Outline neurotoxin wiht examples

act on nerves or motor endplate i.e. Tetanus or Botulinum toxins


What is endotoxin released by

Only produced by Gram-negative bacteria


What is endotoxin

Not a protein but it's the the lipid A moiety of LPS


What is haemolytic-uraemic syndrome

triad of acute renal failure, hemolytic anemia and thrombocytopenia


What are E.coli strains which release shiga toxin known as

EHEC enterohemorrhagic E. coli


When does human infection with EHEC often occur

occurs through the inadvertent ingestion of fecal matter and secondary through contact with infected humans


Why can a shiga toxin bacteria infection affect gut microbiota

Bacterial ribosomes are also a substrate for StxA and this will result in decreased proliferation of susceptible bacteria might affect the commensal microflora in the gut


When are shiga toxins highly expressed

Toxins are highly expressed when the lytic cycle of the phage is activated (so that the gene can be taken up by lots of E coli)


What is the impact of AAF bunding to enterocytes with regard to human immune response

AAF stimulate a strong IL-8 response


What type of bacteria are TB and legionella pneumophilia

TB=gram +ve Legionella=gram -ve


List common bacterial STI

Chlamydia trachomatis infection Gonorrhoea Syphilis


What type of bacteria is each of Chlamydia trachomatis Neisseria gonorrhoeae Treponema pallidum

Gram neg


What cells does N gonorrhoeae interact with

Establishes infection in the urogenital tract by interacting with non-ciliated epithelical cells


Virulence factor of Campylobacter sp. mostly C. jejuni

Adhesion and Invasion factors, Flagella motility, Type IV Secretion system, Toxin


Important virulence factor with vibrio cholerae

type IV fimbria cholera toxin carried on a phages


How does the cholera toxin work

Binds to enterocyte Through b pentamer to the GM1 ganglioside receptor on enterocyte A/B cholera toxins cleves A1 domain from A2 domain, activating A1. A1 faragment enters cytosol, activates Gsa, continually stimulating AC to produce cAMP. High cAMP activates CFTR... efflux of ions (esp chloride) and water from infected enterocytes Leads to diarrhoea


How does listeria infect

Listeria can enter non-phagocytic cells and cross three tight barriers Intestinal barrier, Blood / brain barrier and Materno / fetal barrier