10_Introduction to Enterobacteriaceae

flagella
Shigella and Klebsiella are nonmotile
Oxidase-negative facultative anaerobes
Reduce nitrate
Ferment glucose

and other carbohydrates
Many genera
Escherichia, Salmonella, Shigella, Klebsiella, Proteus, Enterobacter, Yersinia, etc.
Some strains opportunistic pathogens
Some strains true pathogens
Salmonella, Shigella, Yersinia, some strains of E. coli

to N2
Oxidase negative
Distinguishing Properties Associated with All Enterobacteriaceae:

A is toxic component

3. Heat stable

4. Antigenic; ??immunogenicity

5. Toxoids cannot be produced

6. Many effects on host

7. Produced by gram-negative organisms only

EXOTOXIN

1. Released from the cell before
or after lysis

2. Protein

3. Heat labile

4. Antigenic and immunogenic
5. Toxoids can be produced

6. Specific in effect on host

7. Produced by gram-positive and gram-negative organisms

core polysaccharide

antigen is often used to serotype

Arrangements of Flagella

flagellum at one
or both ends of the cell
Multitrichous, two

or several flagella at one
or both ends of the cell
Lateral Flagella arise predominantly from the
middle pole of the cell
Monotrichous, one flagellum
Multitrichous, several flagella in the form
of a tuft originating from the midportion
of the cell
Peritrichous Random, haphazard arrangement of
flagella scattered around the bacterial cell
Mixed Two or more flagella exhibiting distinctly
different physical properties in different regions of the bacterial cell

Taxonomic Descriptions of Prokaryotes Based on Numbers and Arrangements of Flagella (cont.)

considered true pathogens

spp.
Medically Important Enterobacteriaceae

to N2
Oxidase negative
Distinguishing Properties Associated with All Enterobacteriaciae:
REVIEW

A is toxic component

3. Heat stable

4. Antigenic; ??immunogenicity

5. Toxoids cannot be produced

6. Many effects on host

7. Produced by gram-negative organisms only

EXOTOXIN

1. Released from the cell before
or after lysis

2. Protein

3. Heat labile

4. Antigenic and immunogenic
5. Toxoids can be produced

6. Specific in effect on host

7. Produced by gram-positive and gram-negative organisms

REVIEW

Arrangements of Flagella
REVIEW

considered true pathogens
REVIEW