1. Spirochetes et.al.
Spirochetes
Mycoplasma
Rickettsia & Chlamydia
Microbiology HTL

2. Spirochetes
x Gram negative, motile, x Heterogenous group
long helical corkscrew of motile organisms
appearance
x Contains one outer
x spirochete flagella - sheath of
endoflagella glycosaminoglycans
x aerobic & facultative x Contains series of
anaerobes cytoplasmic tubules
x reproduce by transverse (body fibrils)
fission
Microbiology HTL

3. Spirochetes
x Family Spirochaaetaceae ( free living, large
spiral organisms )
x Family Treponemataceae
– Genus Treponema – T. pallidum
– Genus Borrelia – B. recurrentis
– Genus Leptospira – L. interrogans
Microbiology HTL

4. Treponema pallidum
Subspecies Disease
Pallidum Syphillis
Pertenue Yaws
Endemicum Endemic syphilis ( Bejel)
Carateum Pinta
Microbiology HTL

5. Characteristics of Treponema
x 0.2 um in diameter up to 15 um in length
x Actively motile, rotating steadily around
their endoflagella even after attaching to
cells
x Spirals are thin and only seen in
immunofluorescent stain or darkfield
microscopy
x Can be stained with silver impregnation mtd
Microbiology HTL

6. Culture
x Has never been cultured continuously on
artificial media, in fertile eggs, or in tissue
culture
x Nonpathogenic treponemes ( Reiter Stain )
can be cultured anaerobically in vitro
x They are saprophytic
Microbiology HTL

7. Growth characteristics
x Microaerophilic organism
x Survives best with 1-4% oxygen
x Grows in a defined medium with 11 amino
acids, vitamins, salts & serum albumin
x Remain motile 3-6 days at 25 degrees, and
in whole blood remain viable for at least 24
hours at 4 degrees  clinical significance
in blood transfusion
Microbiology HTL

8. Reactions & antigens
x Killed by drying or temperature elevation
(42 degrees)
x Immobilized and killed by trivalent arsenic,
mercury & bismuth
x Slow killing time with penicillin, sometimes
tolerance is demonstrated
x Not culturable = hard to characterize
antigens = more than 100 antigens
Microbiology HTL

9. Syphillis
x Acquired Syphillis
x Congenital Syphillis – 10th to 15th fetal week
x Nontreponemal antigen Test – (VDRL)
x Treponemal Antibody test
– Fluorescent Treponemal Antibody (FTA-ABS)
– Particle Agglutination test – TP-PA
Microbiology HTL

10. Trivia
x Most common type of Syphilis is “Rabbit
Syphilis” caused by T.cuniculi
x Natural STD in rabbits producing minor
lesions in the genitalia
x Moral of the story: Doesn’t pay to be too
sexually active like the rabbit! ( Hooray for
bugs bunny )
Microbiology HTL

11. Microbiology HTL

12. Borrelia
x B. reccurrentis causes relapsing fever in
epidemic form
x Transmitted by the human body louse
x Highly flexible and move by rotation &
twisting
x Stain readily with blood stains ( Wright’s &
Giemsa stain )
Microbiology HTL

13. Culture & Growth
x Cultured in media containing blood, serum,
tissue
x Rapidly loses pathogenicity for animal after
repeated culture in vitro
x Multiplication is quick in chick embryo
x Can survive at 4 degrees in infected blood
or culture
Microbiology HTL

14. B. burgdorferi
x Causes lyme disease ( named after the place
Lyme, CT )
x Isolated in children and transmitted thru the
bite of a small ixodes tick
x Characteristic skin lesion, erythema
migrans, along with flu like symptoms with
late manifestations often with arthritis
Microbiology HTL

15. Microbiology HTL

16. Leptospira & leptospirosis
x L. interrogans causes leptospirosis which is
a zoonosis of worldwide distribution
x Contains more than 260 serotypes
x Tightly coiled spirochete and not easily
stainable ( silver impregnation)
x No traditional method of classification due
to high heterogeneity
Microbiology HTL

17. Culture, growth & antigens
x Grow best under aerobic conditions at
28-30 degrees in serum containing semi-
solid media ( Fletcher’s or Stuarts media )
x Derives energy from oxidation of long
chain FA & cannot use aminoacids and
carbohydrates
x Mainstream antigens are called serovars
(many) with rodents & canine urine as main
source
Microbiology HTL

18. Microbiology HTL

19. Mycoplasma
x lack of cell wall x also causes rhinitis -
x obligate intracellular nose of chickens &
parasites & fermenters turkeys
x colonies : fried egg x due to absence of cell
appearance wall can squeeze thru
x long spiral to perfectly small openings ,not
round cocci filterable.
x Mycoplasma pneumoniae – Penicillin &
- atypical Streptomycin Ab
Microbiology HTL

20. Microbiology HTL

21. Rickettsia & Chlamydia: (1)
x Gram(-) bacteria which x R. typhi - endemic
used to be grouped w/ typhus
virus because of its size x R. rickettsi - Rocky
x Chlamydia - 0.2 -0.7 u mountain spotted fever
x Rickettsia - 0.3 - 1.0 u x Coxiella burnetti - Q
x obligate intracellular fever
parasites x Rickettsial diseases are
x R. prowazekii - epidemic all systemic
typhus x C. trachomatis -
Microbiology HTL trachoma ( blindness)

22. Rickettsia & Chlamydia: (2)
x C. psittaci - psittacosis x Chlamydia has 2 cell
(parrot fever) types:
x Rickettsial pathogens are – Chlamydiospore-
carried by arthropods elementary body
(lice, ticks, mites) – Vegetative cell -
x chlamydia are from reticulate body
human to human x most important
x rickettsia reproduce by substance needed by
simple division both from host is
Microbiology HTL
ATP

23. Microbiology HTL

24. Microbiology HTL