17-19. bacteria and domains and characteristics Flashcards
Is Deinococcus radiodurans aerobic, anaerobic, microaerobic?
aerobic
What makes Deinococcus radiodurans resistant to dessication and radiation?
efficient DNA repair proteins that are activated with DNA repair.
consists of mega- and small plasmid and two circular chromosomes
What is one of the smallest self-reproducing bacteria known?
mycoplasmas
What bacteria is pleomorphic, lacks cell walls, and use sterols to stabilize the PM?
mycoplasmas
What is the general cause for walking pneumonia?
mycoplasma pneumonia. uses adherence factors to bind RT cells (increasing virulence factor). ID50 is 100 cells
What type of mycoplasma is the general cause for UTI, premature birth, neonatal meningitis and pneumonia?
ureaplasma urealyticum
What type of organism is chlamydia class of pathogen?
- obligate intracellular parasite, gram negative
2. lack muramic acid (peptidoglycan) in the cell wall.
When in chlamydia most infectious?
- during dormant stage or EB (elementary body)
What stage is after the elementary body stage?
reticular body (RB), this stage reproduces via binary fission
How does chlamydia exit the cell it infected?
- moves from EB–>RB (multiplies)–> becomes EB. at which point it lyses cells and infects new hosts.
- able to exit the lysosome, therefore does not interact with lysosomes
WHat is the only reservoir for chlamydia?
humans
What features of metabolism contribute chlamydia to being an obligate intracellular parasite?
- unable to generate ATP/NAD+
- require precursor for few biosynthetic product formation
- able to perform ETC, ox phos, substrate phosphorylation
Organisms that fall under spirochetes are generally what?
- gram-negative
- chemoheterophilic
- motile via axial filaments
What are three types of spirochetes?
- treponema
- borrelia
- leptospira
What diseases are associated with spirochetes?
- lyme disease
2. syphilis
Lyme disease is commong from what?
most common tick-borne disease
-transport from animal reservoirs, based on complex maturation pathway of tick
What are the stages of Lyme Disease?
- localized : flu-like symptoms with bull’s-eye rash
- disseminated: wk-mo after infection. neurologic abnormality, carditis, arthritis
- late: years later. neuron demyelination, AD, MS
Serological tests (ELISA, or western blot) spirochete isolation and borrelia detection in a patient is a strong indication for what?
Lyme disease
How is lyme disease treated?
- antibiotics, and tick avoidance
Treponema pallidum cause what infection?
syphilis, invades mucosa or skin breaks
- congenital: in utero acquired
- venereal: STI
What are the three stages of syphilis?
- primary: chancre at infection site
- secondary: variable skin rash with latent period
- tertiary: gumma formation in skin, bone, and nervous system
- -gumma (degernative lesion)
How is syphilis treated?
antibiotics in early stages have best effect, education on sexual hygiene and condoms
Leptospirosis occurs when leptospira interrogans is transferred from dog/rats to skin from urine contaminated water.
True, but must reach a mucosa on host to infect
HA, muscle aches, fever, renal failure are symptoms/signs of leptospirosis
true
What can occur if leptospirosis is not treated?
meningitis, death, liver failure
Doxycycline is commonly used to treat what?
leptospirosis
Alphaproteobacteria is a category of bacteria with what type of characteristics?
- bacteria abundant in oceans
- metabolically diverse function
- oligotrophic bacteria (high oxygen content)
Rickettsia
gram(-), non-flagellated parasite living in blood sucking arthopods
Where can rickettsia grow?
vertebra erythrocytes, macrophages, endothelial cells
What are three features unique to rickettsia metabolism?
- no glucose utilization
- glutamate and TCA intermediate oxidization
- use ATP, and material from host .
Rickettsia is responsible for causing typhus and rocky mountain spotted fever
true
prowazekii/typhi= typhus
rickettsii= rocky mtn spotted fever
What is the difference between epidemic and endemic typhus?
reservoir = rodents for both
causative agent are different and vectors are different
symptoms are the same relatively
What is the cause and vector for epidemic typhus?
prowazekii
and lice respectively
What is the cause and vector for endemic typhus?
typhi and fleas respectively
How does rickettsia reproduce?
enters via phagocytosis, escapes the phagosome and phagolysosome, reproduce in cytoplasm until the host cell burst. process repeats. most common in macrphages or endothelial cells
What is transovarian passage?
passage of bacteria to generation via eggs
What does rocky mountain spotted fever look similar to?
measles like rash, present on palms and soles and rest of body
