-
8/10/2019 Enterotoxins Are Exotoxins That Are Associated With
Diarrhoeal Diseases and Food Poisoning
1/5
Enterotoxins are exotoxins that are associated with
diarrhoeal
diseases and food poisoning, Bacteria Producing enterootoxins
are
V. Cholerae , Enterotoxigenic E. Coli (ETEC), Some strains of
S,
ureus , . Parahaemol!ticus, ". enterolitica, aeromonas
species
and c.p perfringens.
Toxoid, Toxoid is modified exotoxin. n exotoxin has two main
properties
#. Toxicit! and
$. ntigenicit!.
%n Toxoid, the toxicit! of the Toxin is destro!ed &ut its
antigenicit!
is preser'ed. s such toxoids e.g dipetheria toxoid, tetanus
toxoid
can &e safel! used for 'accines. Toxins can &e con'erted
to toxoid
&! different methods e.g. formalin treatment
E*T*+%S
Endotoxins are the integral part of the cell walls of
ram-negati'e
&acteria, and are li&erated when &acteria are
disintegrated
("SE) cell wall of ram negati'e &acteria contain
lipopl!acchaides (PS, endotoxins) which consist of
(#) ioida/ This is the endotoxins and is the core and
($) Pol!saccharide form coat/ This is the * antigen which
caninduce specific immunit!. Pathological and clinical effects
are/
-
8/10/2019 Enterotoxins Are Exotoxins That Are Associated With
Diarrhoeal Diseases and Food Poisoning
2/5
#. Fever: Chill is due to widespread arteriolar and 'enular
constriction.
$. Leucopenia: *ccurs earl! with onset of fe'er. %t ma!
&e
followed &! leucoc!tosis.
0. Hypotension:*ccurs earl! in ram-nageti'e &acteraemia.
1. Shock: Endotoxins or 2septic3 shoc4 ma! de'elop in se'er
ram-negati'e &acteraemia.
5. Death:ma! occur due to shoc4 and 6or %C. 3 n'ria ($778).
Endotoxins
#. 9ormed onl! &! ram-negati'e &acteria
$. lipoppl!saccharides, lipid portion is responsi&le for
toxicit!
0. o specific receptor
1. :odertel! toxic. 9atal to animals in large doses
5. relati'el! heat sta&le. Toxicit! is not destro!ed
a&o'e ;7oC for
hours.
;. usuall! produce fe'er in the host &! release of
interleu4in-# and
other mediators.
. S!nthesis directed &! chromosomal genes
Exotoxins
-
8/10/2019 Enterotoxins Are Exotoxins That Are Associated With
Diarrhoeal Diseases and Food Poisoning
3/5
#. Excreted &! li'ing cells
$. produce &! ram positi'e and ram-negati'e &acteria
0. Pol!peptids
1. ?suall! &ind to specific receptors on cells
5. @ighl! small does
;. relati'el! heat la&ile. Toxicit! destro!ed o'er ;7oC
-
8/10/2019 Enterotoxins Are Exotoxins That Are Associated With
Diarrhoeal Diseases and Food Poisoning
4/5
&acteria &ut is a structural component in the
&acteria which is
released mainl! when &acteria is l!sed.
Their usefulness as antigen .
o Exotoxin / 'er! good, long- lasting immunit! conferred .
o Endotoxin / wea4 , no immunit! conferred .
Lethal dose.
Exotoxin / Small
Endotoxin / arge
onversion to toxiod for!.
Exotoxin / !es &! chemical treatment
Endotoxin / o
haracteristics Exotoxins Endotoxin.
Source li'ing gram l!sed gram
Positi'e and negati'e
ram negati'e &acteria
Bacteria
ocation Deleased from part of
The cell cell
Chemical protein lipopol!saccarid
Composition e .
-
8/10/2019 Enterotoxins Are Exotoxins That Are Associated With
Diarrhoeal Diseases and Food Poisoning
5/5
@eat lia&le sta&le
Sensiti'it! (;7 ;7c) ($57c)
%mmune strong wea4
Deactions
Con'ersion possi&le not possi&le
To toxoids
9e'er no !es
Specificit! specific to non
Particular specific
Bacterial
Strain
ntigenicit! high poor
Examples streptococcus salmonelle
t!phi
