Gram-negative bacteria

Question 1

What are virulence factors?

Answer 1

Any product or strategy that contributes to pathogenicity

Question 2

Name some colonisation factors

Answer 2

adhesins, invasins, nutrient acquisitio

Question 3

What shape are coliforms?

Answer 3

Rod-shaped

Question 4

Are coliforms motile?

Answer 4

Most are due to peritrichous flagella

Question 5

What do coliforms colonise?

Answer 5

The intestinal tract

Question 6

True or false: negative bacteria are facultatively anaerobic

Answer 6

True

Question 7

Enterobacteriaceae consists of multiple gram negative ___-shaped bacterial species

Answer 7

rod

Question 8

Lactose fermentation produces ____

Answer 8

acid (used to distinguish between bacteria)

Question 9

Which 2 bacteria show lactose use (ferment it to make acid) on appearance on MacConkey?

Answer 9

Escherichia coli and Klebsiella pneumoniae

Question 10

MacConkey-lactose agar shows lactose fermenters in what colour?

Answer 10

Red (due to acid)

Question 11

What colour do lactose fermenters turn phenol red in media?

Answer 11

Yellow

Question 12

Do either salmonella or shigella ferment lactose?

Answer 12

No, neither

Question 13

What are the flagellum made of?

Answer 13

Protein

Question 14

What are the principal infections caused by pathogenic E. coli

Answer 14

Wound infections, UTIs, Gastroenteritis, Travellers’ diarrhoea, bacteraemia, meningitis (infants)

Question 15

ETEC stimulates a chlorine transporter in the intestinal lumen to release i___ and w___ through toxins which leads to watery diarrhoea

Answer 15

ions and water

Question 16

What does shigellosis cause?

Answer 16

Severe bloody diarrhoea

Question 17

Where is shigella common?

Answer 17

In developing countries where sanitation is poor

Question 18

True of false: Shigella is acid-tolerant

Answer 18

True

Question 19

How does shigella spread?

Answer 19

Person-to-person, contaminated water and food

Question 20

Shigella enters through colonic _ cells which overlie lymphoid follicles and deliver antigens to underlying immune cells

Answer 20

M

Question 21

How does the shiga toxin in shigella cause cell death?

Answer 21

inhibits protein synthesis

Question 22

What are the 2 species of salmonella?

Answer 22

S. enterica and S. bongori (rare - contact with reptiles)

Question 23

What are the 3 forms of salmoellosis caused by S. enterica

Answer 23

Gastroenteritis
Enteric fever - typhoid
Bacteraemia

Question 24

How does salmonellosis occur?

Answer 24

invades gut epithelium
Transcytosed to basolateral membrane
Enters submucosal macrophages
Intracellular survival

Question 25

Pseudomonas aeruginosa

Answer 25

Ubiquitous (found everywhere), free-living, motile, rod-shaped, opportunistic, resistant to multiple antibiotics

Question 26

Thick mucus in cystic fibrosis increases risk of infection via m____ version of P. aeruginosa

Answer 26

mucoidal

Question 27

Vibrio Cholerae

Answer 27

Facultative anaerobe (makes ATP by aerobic respiration if oxygen is present, but is capable of switching to fermentation), saline environments

Question 28

True of false: Cholera is the most severe diarrhoeal disease

Answer 28

True

Question 29

How is V. cholerae spread?

Answer 29

Faecal-oral (not person-to-person)

Question 30

Most cases of V. cholerae can be treated with ___

Answer 30

ORT (oral rehydration therapy)

Question 31

Campylobacter shape

Answer 31

Spiral rods

Question 32

The flagella of campylobacter are either u_____ or b___

Answer 32

unipolar or bipolar

Question 33

Symptoms of campylobacter

Answer 33

Mild to severe diarrhoea, often with blood

Question 34

True or false: salmonella is the most common cause of food poisoning in UK and US?

Answer 34

False - campylobacter is

Question 35

Helicobacter pylori shape

Answer 35

Spiral-shaped

Question 36

Helicobacter pylori plays a major role in gastritis and p__ u___ disease

Answer 36

peptic ulcer

Question 37

Haemophilus influenzae is an opportunistic injection seen mainly in young children and adult _____

Answer 37

smokers

Question 38

H. influenzae can penetrate the n__________ epithelium

Answer 38

nasopharyngeal

Question 39

H. influenzae has built resistance to phagocytosis and c_____ system

Answer 39

complement

Question 40

Bordetella pertussis

Answer 40

Short rods, fastidious (depends on cleanliness)

Question 41

What is pertussis also known as

Answer 41

Whooping cough

Question 42

True or false: Bordetella pertussis is highly contagious through aerosol transmission

Answer 42

true

Question 43

Legionella pneumophila

Answer 43

Immunocompromised, causes severe inflammatory pneumonia, infection from man-made aquatic environments

Question 44

Can legionella pneumophila replicate within alveolar macrophages

Answer 44

Yes

Question 45

Legionella pneumophila r______ within freshwater protosoa (intracellular parasite of amoeba)

Answer 45

replicates

Question 46

Bacteroides

Answer 46

Non-motile rods, commensal flora *large intestine), opportunistic

Question 47

What is the most frequent cause of anaerobic infections?

Answer 47

Bacteroides (B. fragilis)

Question 48

Bacteroides is often present in polymicrobial infections with e_______

Answer 48

enterobacteria (Presence of facultative anaerobes depletes O2, allowing anaerobes such as Bacteroides to proliferate)

Question 49

Neisseria is a non-flagellated d_____

Answer 49

diplococci

Question 50

What does neisseria meningitidis cause?

Question 51

Neisseria gonorrhoeae causes

Answer 51

Gonorrhoea (second most common STD worldwide)

Question 52

Can gonorrhoea be asymptomatic?

Answer 52

Yes

Question 53

Gonococci are non-c____

Answer 53

capsulated

Question 54

Spirochaetes are longer, slender, h_____ and highly flexible

Answer 54

helical

Question 55

Borrelia burgdorferi causes what disease?

Answer 55

Lyme disease