LECTURE 2 MARK WAEL
Salmonella Shigella
(Salmonella enterica)
Gram -ve, Motile, Non-capsulated, Gram -ve, non-motile, non-
non-spore forming, facultative capsulated, non-spore forming,
Morphology anaerobe facultative anaerobe.
Due to DNA-DNA hybridization
Classification -
1) S. typhi & S. paratyphi A, B, C 1) Sh. Dysentery (severest) has 13
(enteric fever) serotypes.
2) S. typhimurium & S. enteritidis 2) Sh. Flexerni has 8 serotypes.
(enterocolitis)
Serotypes 3) Sh. Boydii has 18 serotypes.
3) S. choleraesuis (septicemia with
metastatic abscess) 4) Sh. Sonnie (commonest) has 1
type
1) MacConkey 1) MacConkey
2) DCA 2) DCA
3) Simple media
Culture
, LECTURE 2 MARK WAEL
1) Most of them produce H2S. 1) They don’t produce H2S
2) They ferment glucose, maltose & 2) Sh. Dysentery ferment glucose
mannite. producing acid
A- Acid only (S. typhi)
B- Acid + gas (S. paratyphi A) 3) Sh. Boydii, sonnie& flexerni
C- Acid + gas + H2S (S. ferment glucose and mannite
Biochemical paratyphi B) producing acid only.
reaction
3) They don’t ferment sucrose & 4) Sh. Sonnie are late lactose
lactose (So make pale yellow on fermenter.
macCokney)
5) Urease is negative
4) Idole & urease negative
1) Somatic O antigen (divides them They are classified according to
to groups) somatic O antigen only.
Antigens
2) Flagellar H antigen (divides them
to serotypes)
3) Capsular VI antigen
1) Invasiveness of distal ileum and
Virulence colon without reaching blood.
factor -
2) Shiga toxin (by dysentery type 1)
which is heat labile exotoxin act as
A- enterotoxin (diarrhea)
B- Neurotoxin (meningism)
Salmonella Shigella
(Salmonella enterica)
Gram -ve, Motile, Non-capsulated, Gram -ve, non-motile, non-
non-spore forming, facultative capsulated, non-spore forming,
Morphology anaerobe facultative anaerobe.
Due to DNA-DNA hybridization
Classification -
1) S. typhi & S. paratyphi A, B, C 1) Sh. Dysentery (severest) has 13
(enteric fever) serotypes.
2) S. typhimurium & S. enteritidis 2) Sh. Flexerni has 8 serotypes.
(enterocolitis)
Serotypes 3) Sh. Boydii has 18 serotypes.
3) S. choleraesuis (septicemia with
metastatic abscess) 4) Sh. Sonnie (commonest) has 1
type
1) MacConkey 1) MacConkey
2) DCA 2) DCA
3) Simple media
Culture
, LECTURE 2 MARK WAEL
1) Most of them produce H2S. 1) They don’t produce H2S
2) They ferment glucose, maltose & 2) Sh. Dysentery ferment glucose
mannite. producing acid
A- Acid only (S. typhi)
B- Acid + gas (S. paratyphi A) 3) Sh. Boydii, sonnie& flexerni
C- Acid + gas + H2S (S. ferment glucose and mannite
Biochemical paratyphi B) producing acid only.
reaction
3) They don’t ferment sucrose & 4) Sh. Sonnie are late lactose
lactose (So make pale yellow on fermenter.
macCokney)
5) Urease is negative
4) Idole & urease negative
1) Somatic O antigen (divides them They are classified according to
to groups) somatic O antigen only.
Antigens
2) Flagellar H antigen (divides them
to serotypes)
3) Capsular VI antigen
1) Invasiveness of distal ileum and
Virulence colon without reaching blood.
factor -
2) Shiga toxin (by dysentery type 1)
which is heat labile exotoxin act as
A- enterotoxin (diarrhea)
B- Neurotoxin (meningism)
