harder clinical micro Flashcards
what do paneth cells shed, as part of their protection against infection
cryptins and hydrolysing enzymes (target bacteria cell wall)
what prevents the action of antibiotic in M.tb
mycelia acid in cell membrane
what anchors the LPS of gram negative bacteria
Lipid A
when Lipid A lets go of LPS
heightened immune reponse- acts as an endotoxin
which proteins in the plasma membrane is targeted by antibiotics
colistin and polymyxin
defensins are rich in
arginine and cystein and highly amphiphatic. The disulphide links mean it has a quaternary sturcture
3 examples of antimicrobial peptides (part of the innate immune system)
defensins, cationic peptides, bacteriocins
cationic peptides EXAMPLE
Cathelicidin- produced by neutrophils and respiratory epithelial cells
are bacteriocins produced by humans
no, by bacteria, including normal microbiota- lethal to closely related species- reduce competition
examples of bacteriocins
Colicins and sakacins
colicins are produced by
ecoli
sakacins are produced by
lactobacilli
antimicrobials are much more attracted to
bacteria membrane due to there being a stronger electrostatic and hydrophobic interaction
name two secreted enzyme defences
Leukocidins and Coagulase
what do bacteria secrete to get iron from host cells
sederphore- rips iron away
exotoxins are
produced by gram positive bacteria- extracellular
endotoxins are
produced by gram negative bacteria - found n cell wall- released when cell dies
stain used for TB
acid fast
acid fast stain used for tb
ziehl neelson stain- added to sputum
stain used for fungi
PAS- periodic acid shift
which medium used to isolate staphylococci
mannitol salt agar
clinical microbio in looking at antibiotic resistance
can use molecular and mass spec methods
molecular methods of determining antibiotic resistance
PCR methods: Nucleic acid base and Next generation sequencing
mass spec methods of deterring antibiotic resistance
MALDI-TOF and ESI, reliant on a data base of town patterns
in next generation sequencing, whichh areas of DNA are looked t and why
16s rRNA- hypervariable and diff in every species
which test is used frequently in establishment of viral infections
agglutination assays
what is M protein
a virulence factor on streptococci that is necessary for the bacteria’s ability to cause strep throat.
Agglutination assays process
-lates beads are artificially coated with antibodies specific to the antigen of interest. Then drop of sample added and if the mixture agglutinates it will clump together–> antibody/antigen complex
