E.coli, Klebsiella, Proteus

Question 1

What kind of bacteria re E.coli, Klebsiella and Proteus?

Answer 1

Facultative pathogenic enteric bacteria

Question 2

What does facultative bacteria mean?

Answer 2

Aerobes or anaerobes that can respire using oxygen or ferment when oxygen is absent

Question 3

To what family does E.coli, Klebsiella and Proteus belong to?

Answer 3

Enterobactericae

Question 4

Outline the species of enterobactericae

Answer 4

E.Coli (escherichia coli)
Klebsiella
Proteus

Question 5

To what groups are the family of enterobactericae split into? Explain what they are.

Answer 5

1) Primary Pathogens:
> organisms that can cause disease in anyone

2) Opertunistic Pathogens
> organism that can only cause disease under certain conditions or certain hosts

Question 6

Give examples of primary pathogens of enterobactericae

Answer 6

> salmonella
shigella
Yersimia

Question 7

Give examples of opportunistic pathogens of enterobactericae

Answer 7

> proteus

> enterobacter

Question 8

Which species share primary pathogenic and opportunistic pathogenic characteristic

Answer 8

> escherichia coli

> klebsiella pneumonia

Question 9

Outline features of all enterbactericae

Answer 9

> facultative anaerobes
oxidase negative - no cytochrome oxidase
reduce nitrates > nitrites
all ferment glucose

Question 10

Is enterbactericae gram negative or gram positive?

Answer 10

Gram negative
> thin peptidoglycan
> NO purple stain
> stain pink - safari/ fuchsin

Question 11

What shape are enterobactericae?

Answer 11

rod shape

Question 12

Do all or some enterobactericae have flagella? what type of flagella and what does it mean?

Answer 12

> some have petrichious flagella&raquo_space; means all around surface
motile function

Question 13

Do all or some enterobactericae have a capsule, outline function if they do?

Answer 13

> some have capsule

> protective function

Question 14

Do all or some enterobactericae have endotoxins? Outline function of endotoxin

Answer 14

> ALL have endotoxins
lipopolysaccharide in gram negative bacteria
molecule initiates inflammatory response in host

Question 15

Do all or some enterbactericae have enterotoxins? Outline function of enterotoxins and give examples

Answer 15

> some have enterotoxins

> protein exotoxin mainly targeting intestines

Question 16

How often does plasmid and DNA exchange take place in enterbactericae and why?

Answer 16

> frequent exchange

> can develop antibiotic resistance

Question 17

Which species of enterobactericae causes urinary tract infection (UTI), travellers diarrhoea and neonatal meningitis ?

Answer 17

Escherchiae Coli enterobactericae

Question 18

What diseases does escherchia coli enterobactericae cause?

Answer 18

> urinary tract infection (UTI)
neonatal meningitis
travellers diarrhoea

Question 19

What is travellers diarrhoea? Which species causes it?

Answer 19

> digestive disorder
due to contaminated food/ drinks
not very serious
caused by escherichia coli (E.coli)

Question 20

What is neonatal meningitis? Which species causes it? How is it treated?

Answer 20

> inflammation of meninges during first 28 days of life
bacteria enter bloodstream and reach brain
treated with antibiotics, given through IV

Question 21

What diseases does shigella cause?

Answer 21

Dysentery: infection of intestines&raquo_space; causing diarrhoea with blood/ mucus

Question 22

Which enterobactericae causes dysentery?

Answer 22

> shigella

Question 23

Which diseases does Salmonella cause?

Answer 23

> typhoid fever

> enterocolitis

Question 24

Which species causes typhoid fever and enterocolitis?

Answer 24

> salmonella

Question 25

What is typhoid fever? Which species causes it? How is it treated?

Answer 25

> bacterial infection caused by salmonella > spread through body + affect many organs > caused by drinking contaminated water or food washes in contaminated water > treated with antibiotics

Question 26

What is enterocolitis and which species causes it?

Answer 26

> inflammation of digestive tract > bacteria: salmonella > enteritis of intestines > colitis of colon (inflammation of inner lining of colon)

Question 27

What diseases are caused by klebsiella?

Answer 27

> pneumonia | > UTI

Question 28

Which species causes UTI and pneumonia?

Answer 28

klebsiella

Question 29

What disease is caused by proteus?

Answer 29

UTI

Question 30

Outline the species which can cause UTI

Answer 30

klebsiella proteus enterobacter escherechia coli

Question 31

Describe the typical colonies of enterobactericae?

Answer 31

> circular > convex > glistering (S) or mucoid (M)

Question 32

Describe colonies of enterbactericae with the loss of capsule?

Answer 32

> rough (R) colonies > flat irregular > granular in appearance

Question 33

Describe colonies of highly motile species: proteus

Answer 33

> unique swarming pattern

Question 34

Which species forms inquire swarming pattern on agars?

Answer 34

> highly motile: proteus

Question 35

What colour pigment of colonies do some strains of enterobactericae produce?

Answer 35

> red > yellow > blue

Question 36

What determines pathogenicity of enterobactericae species?

Answer 36

> Major antigens | > Virulent factors

Question 37

Outline all different major antigens

Answer 37

O-somatic Ag = all K-capsule Ag = some H-flagellar Ag = most F-fimbriae Ag = some

Question 38

For each Ag, outline its type: | O, K, H, F antigens

Answer 38

> O = somatic > K = capsule > H = flagella > F = fimbriae

Question 39

Which species has more than 160 O Antigens?

Answer 39

Escherichia coli

Question 40

What happens when O Ag are lost?

Answer 40

transform colonies from S to R

Question 41

R colonies are known as what bacteria?

Answer 41

Avirulent - not virulent or pathogenic - doesn't cause infection

Question 42

What do K-Ag consist of and what do they cover?

Answer 42

> consists of polysaccharide | > cover O-Ag

Question 43

How are K-Ag destroyed?

Answer 43

> with boiling water

Question 44

How do K-Ag block agglutination?

Answer 44

> they cover O-Ag | > block agglutination of O-specific antiserum

Question 45

What are H-Ag known as and what is it useful for?

Answer 45

flagellar protein antigens

Question 46

Which species is non motile and therefore what does it mean about their Ag?

Answer 46

Klebsiella | > NO H-Ag

Question 47

How many phases of H-Ag does Salmonella species have? Which are they and what do they depend on?

Answer 47

> 2 phases of H-Ag - H1 phase - H2 phase > depends on gene expression of bacteria

Question 48

Which species has 2 phases of H-Ag?

Answer 48

Salmonella species | > H1 + H2 phase

Question 49

What kind of test can be used for identification for the three Ag (O,K,H)?

Answer 49

> serological strain identification made with specific antisera for the 3 Ag >> O,K,H antigens

Question 50

Outline the virulent factors which determine the pathogenicity of enterbactericae?

Answer 50

> endotoxins (LPS) > exotoxins (enterotoxins) > fimbriae (adhesion) > capsule + other protective surface Ag)

Question 51

What happens when enterobacteria LPS are released in host body?

Answer 51

endotoxin shock in humans

Question 52

Outline the effects of LPS?

Answer 52

> small dose: toxic effect > large dose: lethal effect > fever within 30min of exposure > hypotension within 30min > intravascular coagulation (localised + generalised) >> clotting factor >> bleeding > neutropenia = low levels of neutrophils >> monoblasts appear in circulation

Question 53

What are monoblasts?

Answer 53

> bone marrow origin | > mature into monocytes which develop into macrophages

Question 54

Is LPS endotoxin or exotoxin?

Answer 54

endotoxin

Question 55

To which cell does LPS cause stimulation and proliferation?

Answer 55

> B-lymphocytes

Question 56

LPS cause macrophages to release what?

Answer 56

> interleukin 1 (IL1) | > lysosomal enzymes

Question 57

Which pathways are activated and what is stimulated?

Answer 57

> complement and alternative pathways activated | > stimulate interferon activity

Question 58

How does LPS affect metabolism? What does it cause?

Answer 58

causes: > hypoglycemia > hypoferremia (low iron blood)

Question 59

Describe LPS effect in pregnancy?

Answer 59

> placental haemorrhage because it stimulates release of serotonin

Question 60

What are the 5 genre of tribe escherichia?

Answer 60

facultative pathogenic flora: > escherichia > edwardsiella > citrobacter enteric pathogens: > salmonella > shigella

Question 61

Where is E.coli found in humans?

Answer 61

large bowel

Question 62

What type of contamination is it when E.coli is found in drinking water?

Answer 62

fecal contamination

Question 63

Is E.coli hemolytic or non haemolytic?

Answer 63

> haemolytic = specifically in urine isolates | > cause gastroenteritis