Lecture 9 - Neisseria Flashcards
name the neisseria species commonly associated with human disease
neisseria meningitidis
neisseria gonorrhoeae
give a major difference between neisseria meningitidis and neisseria gonorrhoeae
meningitidis has a polysaccharide capsule and gonorrhoeae does not
what about the 2 neisseria species makes it so difficult for the immune system to keep up?
their pilli are antigenically diverse
how is neisseria meningitidis transmitted?
through inhalation of respiratory droplets
how is neisseria gonorrheae transmitted?
sexual contact of mucosal surfaces
what are the diseases caused by neisseria meningitidis
meningitis and septic shock
what are the diseases caused by neisseria gonorrhoeae
urethritis, cervicitis, and pelvic inflammatory disease
neisseria bacteria are gram _____
negative
are any of the neisseria bacteria we’re studying commensal?
meningitis colonizes the nasopharynx, while gonorrheae is not commensal
explain the shape of neisseria bacteria
gram negative, flat sided, diplococci
neisseria are ____(aerobic, facultative, or anaerobic), oxidase _____ and most are catalse ______
AEROBIC, oxidase positive, and most are catalse positive
does neisseria undergo oxidation or fermentation?
oxidation
neisseria meningitis produces _____ through oxidation while neisseria gonorrhoeae produce ____ through oxidation
neisseria meningitidis — glucose and maltose
neisseria gonorrhoeae – glucose
differentiate between the capsules of neisseria meningitidis and neisseria gonorrheae
meningitisi — has 13 serogroups of its capsule, with the most infectious being A,B,C,Y, and W135
Gonorrheae does not have a capsul
explain the pilli of neisseria bacteria
composed of pilin subunits. the expression is regulated by a pil gene complex – which gives antigenic diversity
the pili regulate attachment, transfer of genetic material, and give some motility
true or false
a mutation in neisseria bacteria gives it the ability to express antigenic diversity in its pili
FALSE – its not a mutation
its a normal pil gene complex
where does neisseria meningitidis colonize
the nasopharynx
neisseria competes with the host cell for WHAT and HOW
for iron
through transferrin, lactoferrin, and hemoglobin binding proteins
true or false
neisseria has endotoxin activity
TRUE – has LOS (lipoligosaccharide)
contains the lipid A and core oligosaccharide portion of LPS
endotoxin
explain the virulence factors that neisseria has to evade the immune system
igA proteases – cleave hinge region of IGA (neisseria colonizes in nasopharynx, and neisseria gonorrheae is transmitted via sexual mucosal contact)
beta lactamases to degrade penicillin and other beta lactams
what does neisseria have that enables it to facilitate invasion into epithelial cells?
porin proteins
they interfere with neutrophil degranulation
explain the pathogenesis of neisseria gonorrheae
attaches and penetrates host mucosal cells via their pilli and Porin B protein
multiply INTRACELLULARLY and establish infection in the sub epithelial space
promote inflammation via LOS and TNF alpha
where does neisseria gonorrhea multiply ?
intracellularly
where does neisseria gonorrhea establish the infection?
in the subepithelial space
can neisseria gonorrhoeae get into the bloodstream?
NO – they lack a capsule and are thus engulfed by neutrophils before they reach the bloodstream
however, neisseria meningitidis is encapsulated and can get into the blood
name the diseases caused by neisseria meningitidis
meningitis
septicemia
pneumonia
arthritis
