17-19. bacteria and domains and characteristics

Question 1

Is Deinococcus radiodurans aerobic, anaerobic, microaerobic?

Answer 1

aerobic

Question 2

What makes Deinococcus radiodurans resistant to dessication and radiation?

Answer 2

efficient DNA repair proteins that are activated with DNA repair.
consists of mega- and small plasmid and two circular chromosomes

Question 3

What is one of the smallest self-reproducing bacteria known?

Answer 3

mycoplasmas

Question 4

What bacteria is pleomorphic, lacks cell walls, and use sterols to stabilize the PM?

Answer 4

mycoplasmas

Question 5

What is the general cause for walking pneumonia?

Answer 5

mycoplasma pneumonia. uses adherence factors to bind RT cells (increasing virulence factor). ID50 is 100 cells

Question 6

What type of mycoplasma is the general cause for UTI, premature birth, neonatal meningitis and pneumonia?

Answer 6

ureaplasma urealyticum

Question 7

What type of organism is chlamydia class of pathogen?

Answer 7

1. obligate intracellular parasite, gram negative

2. lack muramic acid (peptidoglycan) in the cell wall.

Question 8

When in chlamydia most infectious?

Answer 8

1. during dormant stage or EB (elementary body)

Question 9

What stage is after the elementary body stage?

Answer 9

reticular body (RB), this stage reproduces via binary fission

Question 10

How does chlamydia exit the cell it infected?

Answer 10

1. moves from EB–>RB (multiplies)–> becomes EB. at which point it lyses cells and infects new hosts.
2. able to exit the lysosome, therefore does not interact with lysosomes

Question 11

WHat is the only reservoir for chlamydia?

Answer 11

humans

Question 12

What features of metabolism contribute chlamydia to being an obligate intracellular parasite?

Answer 12

1. unable to generate ATP/NAD+
2. require precursor for few biosynthetic product formation
3. able to perform ETC, ox phos, substrate phosphorylation

Question 13

Organisms that fall under spirochetes are generally what?

Answer 13

1. gram-negative
2. chemoheterophilic
3. motile via axial filaments

Question 14

What are three types of spirochetes?

Answer 14

1. treponema
2. borrelia
3. leptospira

Question 15

What diseases are associated with spirochetes?

Answer 15

1. lyme disease

2. syphilis

Question 16

Lyme disease is commong from what?

Answer 16

most common tick-borne disease

-transport from animal reservoirs, based on complex maturation pathway of tick

Question 17

What are the stages of Lyme Disease?

Answer 17

1. localized : flu-like symptoms with bull’s-eye rash
2. disseminated: wk-mo after infection. neurologic abnormality, carditis, arthritis
3. late: years later. neuron demyelination, AD, MS

Question 18

Serological tests (ELISA, or western blot) spirochete isolation and borrelia detection in a patient is a strong indication for what?

Answer 18

Lyme disease

Question 19

How is lyme disease treated?

Answer 19

1. antibiotics, and tick avoidance

Question 20

Treponema pallidum cause what infection?

Answer 20

syphilis, invades mucosa or skin breaks

• congenital: in utero acquired
• venereal: STI

Question 21

What are the three stages of syphilis?

Answer 21

1. primary: chancre at infection site
2. secondary: variable skin rash with latent period
3. tertiary: gumma formation in skin, bone, and nervous system
   - -gumma (degernative lesion)

Question 22

How is syphilis treated?

Answer 22

antibiotics in early stages have best effect, education on sexual hygiene and condoms

Question 23

Leptospirosis occurs when leptospira interrogans is transferred from dog/rats to skin from urine contaminated water.

Answer 23

True, but must reach a mucosa on host to infect

Question 24

HA, muscle aches, fever, renal failure are symptoms/signs of leptospirosis

Answer 24

true

Question 25

What can occur if leptospirosis is not treated?

Answer 25

meningitis, death, liver failure

Question 26

Doxycycline is commonly used to treat what?

Answer 26

leptospirosis

Question 27

Alphaproteobacteria is a category of bacteria with what type of characteristics?

Answer 27

1. bacteria abundant in oceans
2. metabolically diverse function
3. oligotrophic bacteria (high oxygen content)

Question 28

Rickettsia

Answer 28

gram(-), non-flagellated parasite living in blood sucking arthopods

Question 29

Where can rickettsia grow?

Answer 29

vertebra erythrocytes, macrophages, endothelial cells

Question 30

What are three features unique to rickettsia metabolism?

Answer 30

1. no glucose utilization
2. glutamate and TCA intermediate oxidization
3. use ATP, and material from host .

Question 31

Rickettsia is responsible for causing typhus and rocky mountain spotted fever

Answer 31

true
prowazekii/typhi= typhus
rickettsii= rocky mtn spotted fever

Question 32

What is the difference between epidemic and endemic typhus?

Answer 32

reservoir = rodents for both
causative agent are different and vectors are different
symptoms are the same relatively

Question 33

What is the cause and vector for epidemic typhus?

Answer 33

prowazekii

and lice respectively

Question 34

What is the cause and vector for endemic typhus?

Answer 34

typhi and fleas respectively

Question 35

How does rickettsia reproduce?

Answer 35

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

Question 36

What is transovarian passage?

Answer 36

passage of bacteria to generation via eggs

Question 37

What does rocky mountain spotted fever look similar to?

Answer 37

measles like rash, present on palms and soles and rest of body