ch 5 Neisseria Flashcards
Neisseria spp gram stain
Gram negative, diplococci (kidney shaped).
Growth temp for Pathogens and Commensals
37°C
20-42°C Optimal temp. 37°C
CO2 requirement
pathogenes: 5-10% CO2
Commensals : Do not need
media for pathogenes
Grow on chocolate chocolate agar
agar
media Commensals
Can grow on nutrient agar, blood agar, chocolate agar, Muller-Hinton agar
TM medium
Pathogens : can grow
Commensals : Cannot grow except Neisseria lactamica
Chocolate Agar + 5-10% CO2 for ______ e.g.
for sterile samples
g. blood culture
and CSF)
Thayer Martin Agar (TM) + 5-10% CO2 (for ____
e.g.)
for unsterile samples
e.g. urethral swab and Cervical swab
Colony:
small colorless or grey colonies.
Source of 5-10% CO2
- CO2 incubator 2. Jar + CO2 gas pack 3. Candle jar
Biochemical Reactions
• Catalase positive
• Oxidase positive
is used to identify bacteria containing the respiratory
enzyme
The oxidase test
Positive result in Oxidase Test
à purple color in 15 seconds.
Sugar fermentation test
• Indicator:
phenol red
N. gonorrhoeae ferments
glucose only.
N. meningitidis ferments
glucose and maltose.
N. lactamica ferments
glucose, maltose and lactose.
Neisseria gonorrhoeae cause
Causes gonorrhea
It has vaccine because the virulence factor for it is the pili صح او خطا
خطا
What are the complications of gonorrhea?
infertility
Virulence factors of N. gonorrhoeae:
Polyphosphates
Pili
IgA protease
Specimens Neisseria gonorrhoeae
Urethral swab
Cervical swab
Rectal swab
Throat swab
Blood culture
Neisseria meningitidis cause
It causes meningococcal meningitis and acute purulent meningitis
Sources of infection Neisseria meningitidis
Case
Carrier