Bacterial taxonomy

Question 1

Define a prokaryote

Answer 1

A cell with no membrane bound organelles i.e. bacteria

Question 2

Define a facultative anaerobe

Answer 2

A cell capable of aerobic and anaerobic respiration

Question 3

Define an obligate anaerobe

Answer 3

Cells which die in the presence of oxygen

Question 4

Define an obligate aerobe

Answer 4

Cells which die without the presence of oxygen

Question 5

Enterococcus (stain, shape, oxygen, disease)

Answer 5

Gram positive cocci, facultative aerobes, UTI

Question 6

Difference between enterobacter and enterococcus

Answer 6

Both are faculatative aerobes
EnterobBactEr - gram nEgative Bacillis
EnteroCOccus- gram pOsitive Coccus

Question 7

Moraxella Catarrhalis (stain, shape, oxygen, disease)

Answer 7

Gram negative, coccus, obligate aerobe, associated with respiratory, ear and sinus infections

Question 8

Legionella (stain, shape, oxygen, disease)

Answer 8

Gram negative, bacillus, obligate aerobe, pneumonia

Question 9

Klebsiella (stain, shape, oxygen, disease)

Answer 9

Gram negative, bacillus, facultative anaerobe, pneumonia in the immunosuppressed

Question 10

Bacillus (stain, shape, oxygen, disease)

Answer 10

Gram positive, bacillus, facultative or obligate aerobe, B. anthracis causes anthrax, B. cereus causes food poisoning

Question 11

Corynebacterium (stain, shape, oxygen, disease)

Answer 11

Gram positive, bacillus, facultative anaerobe, diphtheria (upper respiratory tract infection)

Question 12

Listeria (stain, shape, oxygen, disease)

Answer 12

Gram positive, bacillus, facultative anaerobe, infection in pregnancy(stillbirth, preterm labour), neonates (sepsis, meningitis)

Question 13

Clostridium (stain, shape, oxygen, disease)

Answer 13

Gram positive, bacillus, obligate anaerobe, c. tetani - tetanus, c. difficile-gastroenteritis, c.botulinum - botox

Question 14

Actinomyces (Stain, shape, oxygen, disease)

Answer 14

Gram positive, bacillus, facultative anaerobe, intrauterine devices, dental infections

Question 15

Campylobacter (Stain, shape oxygen, disease)

Answer 15

Gram negative, bacillus/s-shaped, facultative anaerobe, gastroenteritis

Question 16

Haemophilus influenza (stain, shape, oxygen, disease)

Answer 16

Gram negative, bacillus, facultative anaerobe, pneumonia

Question 17

Difference between campylobacter and clostridium in terms of taxonomy

Answer 17

CampylobactEr - gram nEgative, s shaped rod, facultative aerobe, causes gastroenteritis
ClOStrIdium- gram pOSItive, rod, obligate anaerobe, c. tetani/difficile/botulinum

Question 18

Proteus (stain, shape, oxygen, disease)

Answer 18

Gram negative, bacillus, facultative anaerobe, wound and urine infections

Question 19

Helicobacter Pylori (stain, shape, oxygen, disease)

Answer 19

Gram negative, bacillus, facultative anaerobe, stomach ulcer

Question 20

Salmonella (stain, shape, oxygen, disease)

Answer 20

Gram negative, bacillus, facultative anaerobe, gastroenteritis

Question 21

Escherichia Coli (stain, shape, oxygen, disease)

Answer 21

Gram negative, bacillus, facultative anaerobe, uti, gastroenteritis

Question 22

Pseudomonas aeroginosa (Stain, shape, oxygen, disease)

Answer 22

Gram negative, bacillus, obligate aerobe, hospital acquired pneumonia

Question 23

Bordetella Pertussis (Stain shape, oxygen, disease)

Answer 23

Gram negative bacillus, obligate aerobe, upper respiratory tract infection

Question 24

What is MacConkey agar?

Answer 24

A growth medium used to identify gram negative bacteria (it kills gram positive bacteria) and to differentiate between lactose fermenting and non-lactose fermenting gram negative rods

Question 25

Give 3 examples of lactose fermenting bacilli

Answer 25

E. coli, klebsiella, enterobacter

Question 26

Give 5 examples of non-lactose fermenting bacilli

Answer 26

Proteus, salmonella, pseudomonas, shigella, h. pylori

Question 27

Give 2 examples of obligate anaerobes

Answer 27

Clostridium (gram positive rod), bacteroides (gram negative rod)

Question 28

Give 3 examples of gram negative obligate aerobic cocci

Answer 28

3 cocci: Neisseria gonorrhoea, Neisseria menigitides, Moraxella catarrhalis

Question 29

What is the catalase test used for?

Answer 29

To differentiate between enterococcus and streptococcus (streptococcae are catalase negative because they cannot hydrolyse hydrogren peroxide to water and oxygen)

Question 30

Which bacteria cannot be differentiated with gram staining?

Answer 30

Chlamydia, mycoplasma and ureaplasm - these bacteria do not have a normal bacterial cell wall, they lack peptidoglycans

Question 31

Bacteroides (stain, shape, oxygen, disease)

Answer 31

Gram negative, rod, obligate anaerobe, GI infection including appendicitis/abscesses

Question 32

What is the purpose of the aesculin test?

Answer 32

Aesculin (from horse chesnuts) with bile salts in agar - aesculin hydrolyses to aesculitin. Aesculitin forms a dark brown/black complex on the agar. Enterococcus (gram positive coccus) - forms black rings in aesculin agar = aesculin positive

Question 33

Which bacteria is aesculin positive?

Answer 33

enterococcus

Question 34

Which bacteria is catalase negative?

Answer 34

Streptococci

Question 35

Gardnerella vaginalis (stain, shape, oxygen, disease)

Answer 35

Gram variable, rod, facultative anaerobe, bacterial vaginosis

Question 36

What does sulphur granules indicate?

Answer 36

Actinomyces

Question 37

Give 3 examoles of gram negative obligate aerobic baccili

Answer 37

3 rods: legionella, pseudomonas, bortadella