Chlamydia Flashcards
To which phylum do Chlamydia and Chlamydophila belong?
Phylum IX (Wall-less Forms)
What family do these genera belong to?
Chlamydiaceae
Are chlamydiae motile or non-motile?
Non-motile
What type of Gram stain result do chlamydiae exhibit?
Gram-negative
What term describes the shape variability of chlamydiae?
Pleomorphic
What kind of parasitic lifestyle do chlamydiae have?
Obligate intracellular parasites
What makes their developmental cycle unique?
They replicate within host cells using a biphasic cycle
Which species causes avian chlamydiosis and psittacosis?
Chlamydophila psittaci
What diseases does C. pecorum cause in cattle?
Sporadic bovine encephalitis, infectious polyarthritis, pneumonia, diarrhea
Which species causes enzootic abortion in sheep?
Chlamydophila abortus
What does C. suis infect in pigs?
Intestinal tract
What condition does C. caviae cause in guinea pigs?
Inclusion conjunctivitis
What is the primary disease caused by C. felis?
Feline pneumonitis (conjunctivitis)
How many serovars does C. trachomatis have?
More than 15 serovars
What mouse pathogen causes respiratory infections?
Chlamydia muridarum
What nucleic acids do chlamydiae possess?
Both RNA and DNA
What three compounds can they metabolize?
Glucose, pyruvate, glutamate
What is their antibiotic susceptibility?
Broad-spectrum antibiotics
What cellular change occurs after phagocytosis?
Forms intracytoplasmic, membrane-limited inclusions
How do reticulate bodies reproduce?
Binary fission
What is the genus-specific antigen of Chlamydia?
LPS with ketodeoxyoctanoic acid
What produces hemagglutinins of Chlamydia?
Elementary bodies only
Where are chlamydiae normally found?
Respiratory and GI mucous membranes
How do elementary bodies persist in the environment?
In soil and feces for long periods
What are the three main virulence factors of Chlamydia
LPS, CPAF protease, Type III secretion system
How does CPAF work?
Degrades host MHC transcription factors
What is a key feature of chlamydial infections?
Latency that can be reactivated
What two staining methods are used for Chlamydia
Giemsa and Gimenez
What brain changes are characteristic?
Purulent meningoencephalitis
What is the human mortality rate if untreated?
Up to 20%
C. psittaci:
Q: What are the avian clinical signs?
Ocular/nasal discharge, sinusitis, conjunctivitis
C. abortus:
Q: What is the incubation period in sheep?
Latent until conception
C. pecorum:
Q: What is the mortality rate in SBE (Sporadic Bovine Encephalomyelitis)?
Up to 50%
C. felis:
Q: What age cats are most affected?
5-12 week old kittens
What is the infectious forms of Chlamydia?
Elementary bodies
What is the Intracytoplasmic form of Chlamydia
Reticulate bodies
All chlamydiae share a genus-specific antigen (T/F)
True
Immunity response for Chlamydia
Both cell-mediated and humoral
What is considered as a putative virulence factor of Chlamydia?
LPS
which allows chlamydia to escape recognition by T-cells, allowing the bacterium to continue its life cycle repeatedly within the host?
CPAF or chlamydial protease or
proteasome-like activity factor
CPAF is unique to and highly conserved among the chlamydiae (T/F)
True
