Non-fermentative Gram Neg Bacilli Glucose Oxidizers

Question 1

Under what condition do these organisms grow?

Answer 1

Obligate aerobe

Question 2

Most of these organisms are oxidase positive. Which are not?

Answer 2

Acinetobacter and Stenoteophomonas

Question 3

What is the most common isolated glucose non-fermenter clinically?

Answer 3

Pseudomonas aeruginosa (rarely normal flora)

Question 4

What is the key pathogen found in patients with cystic fibrosis?

Answer 4

Pseudomonas aeruginosa

Question 5

What is another organism that causes cystic fibrosis?

Answer 5

Burkholderia cepacia

Question 6

causes glanders in horses, mules, etc.

Answer 6

Burkholderia mallei

Question 7

found in soil and rice paddies

Answer 7

Burkholderia pseudomallei

Question 8

this organism is found in hospitalized patients and is the 2nd most common glucose non-fermenter isolated clinically.

Answer 8

Acinetobacter spp.

Question 9

found in respiratory tract of hospital patients and is the 3rd most common glucose non-fermenter isolated clinically.

Answer 9

Stenotrophomonas maltophilia

Question 10

Pseudomonas aeruginosa general info

Answer 10

Glucose oxidizer. oxidase pos. MAC pos. serrated edges and green pigment and metallic sheen. common cause of nosomial infections. TSI Slant- K/K, gas Neg, H2S Neg.

Question 11

list the virulence factors of pseudomonas aeruginosa.

Answer 11

exotoxin A, Alginate, Pyocyanin, Pili, and intrinsic resistance to antimicrobials.

Question 12

Exotoxin A inhibits what?

Answer 12

protein synthesis in host cells

Question 13

what does alginate do?

Answer 13

surface carb that impedes phagocytosis.

Question 14

What does pyocyanin do?

Answer 14

blue pigment produces reactive oxygen species causing tissue damage.

Question 15

What is Pili used for?

Answer 15

for attachment to host cells.

Question 16

list Pseudomonas pigments.

Answer 16

Pyocyanin-blue green (only produced by P. aeruginosa), Pyoverdin- yellow (visualize with UV light), Pyorubin- rust, and Pyomelanin- brown.

Question 17

what is pseudomonas aeruginosa resistant to?

Answer 17

penicillin and ampicillin

Question 18

what is pseudomonas aeruginosa susceptible to?

Answer 18

aminoglycosides, extended spectrum penicillins, carbapenems, and quinolones.

Question 19

what is the most common pathogen for CF in the 1st decade of life?

Answer 19

Staph aureus and Haemophilus influenzae

Question 20

how is burkholderia cepacia spread?

Answer 20

kissing and doorknobs. able to survive on or in medical devices and disinfectants.

Question 21

general info for burkholderia cepacia.

Answer 21

oxidase pos. LDC pos. Polymyxin B resistance.

Question 22

what is media used to help isolate in CF patients.

Answer 22

OFBL and PC

Question 23

general info for burkholderia mallei

Answer 23

MAC pos. Oxidase pos.

Question 24

what do you treat glanders with?

Answer 24

tetracyclines

Question 25

how does glanders transmit?

Answer 25

NO human to human transmission. Contract via cuts and contact with horse tissues/ fluids.

Question 26

general info burkholderia pseudomallei

Answer 26

MAC pos. oxidase pos.

Question 27

how is burkholderia pseudomallei transmitted?

Answer 27

inhalation or inoculation through cuts

Question 28

which organism is the causative agent of Melioidosis (Whitmore's disease)?

Answer 28

burkholderia pseudomallei

Question 29

what is the treatment for melioidosis (Whitmore's disease)?

Answer 29

oral antibiotics (deoxycycline) or intravenous (ceftazidime).

Question 30

general info for Acinetobacter spp.

Answer 30

Oxidase pos. catalase pos. doesn't reduce nitrates to nitrites (P. aeruginosa does). can create a purple hue on MAC though they're NOT lactose fermenters. resistant to many antibiotics.

Question 31

general info for Stenoteophomonas maltophilia.

Answer 31

Strong maltose oxidizer. glucose oxidizer. oxidease NEG. MAC pos. arginine neg. ornithine neg. lysine pos. dnase pos. polymyxin B sensitive.

Question 32

Why do anaerobic organisms use the EMP pathway?

Answer 32

EMP yields more ATP than ED pathway (2 ATP/Glucose)

Question 33

what pathway is seen in more aerobic organisms?

Answer 33

ED pathway

Question 34

why do some organisms use the ED pathway?

Answer 34

ED pathway requires less enzymatic protein to carry out glucose metabolism.

Question 35

what kind of reaction is fermentation?

Answer 35

oxidation-reduction (oxygen is excluded)

Question 36

what reaction does weak acid is formed and no gas produced?

Answer 36

oxidation/oxidative

Question 37

what is the definition of oxidation?

Answer 37

any process in which the oxygen content of a compound is increased; any reaction in which the positive valence of a compound or a radical is increased because of a loss of electrons.

Question 38

what does oxidative of tubes look like?

Answer 38

acid in open tube only