6) Human-microbe interactions Flashcards
Ecological relationships [interaction]
- COMMENSALISM
- MUTUALISM [symbiosis]
- PARASITISM
{+/0} Two species one benefits other not affected
COMMENSALISM
[symbiosis] {+/+} Two species (microbe and host ) both benefit
E.g =
MUTUALISM
E. coli in intestine
{+/-} Two species one benefits (parasite) from the other (host)
Two species ( Infection/disease) اللي يترجم قالها
PARASITISM
the colonization and/or invasion and multiplication of pathogenic microrganisms in the host
INFECTION
an abnormal condition of body functions or structure produce by Microbial factors (virulence) and Host defenses
DISEASE (infectious)
= ability of infectious agent to overcome host defenses mainly by Toxins and
Invasion of tissue (enzymes)
Virulence
ENDOTOXINS
- Lipopolysaccharides (LPS)
- Part of outer membrane
- Do not denatured by boiling
- Poor antigen
- Do not form toxoid
EXOTOXINS
-Proteins - Secreted - Denatured by boiling - Good antigen - form toxoid
Endotoxins
Gram negative bacteria
lipopolysaccharide (LPS ) binds to CD14 and TLR4 then triggering them to secrete pro-inflammatory
{ cytokines and nitric oxide }
that lead to
“endotoxic shock”
Example of enzymes (invasions) ? ممكن مقالي
مثال على الانزيمات * الغزوات*
= Clostridium perfringens
? Relationships of infections at cellular level
Extracellular.
Facultative intracellular
Obligate intracellular
most bacteria,
, fungi, parasites
Extracellular
Mycobacterium,
Brucella, Legionella,,
Dimorphic fungi
Facultative intracellular
Chlamydia, Rickettsia, Toxoplasma, Ehrlichia, Anaplasma
Obligate intracellular
