Microbial Flora Of Human
Body External
-
Internal organs are
generally free of microorganisms
•
.
In this context
•
digestive / urinary
etc .
tracts counts as outside the
body .
Surface tissue has lots of
microorganisms
•
.
•
Collectively the microbial community associated with an
organism is called it microbiome .
Distribution of human microbiome
Some are found outside the
body skin ,
nails hair ,
, eyes) others inside
Types of Microbes
•
Most species
of microbe in
the human microbiome are bacteria .
•
These from birth onwards
colonise .
The population over time
changes
•
.
•
Early colonisers are commensal bacteria .
•
Normally mutualistic / symbiotic relationship with the host :
-
Access to nutrients
-
Defence
-
Multiple factors influence early colonisers .
•
However , occasionally there can be infections .
•
Opportunistic organism which can cause problems for the host .
• Some examples may be long-term incubators .
Microbial adhesion and attack
Healthy ( intact) skin to most bacterial attacks
acts reliable barrier
•
as a .
However to the surface of the skin
microbes will adhere
many
•
.
Some bacteria are able to attach to surfaces and
grow (biofilms)
•
.
•
Often involves attachment of bacterial adhesions to the glycoproteins of
the skin surface .
External Microbial Flora -
Skin
skin the distribution
However although bacteria colonise much
of the is not even
•
can ,
.
•
certain areas have more microbes than others .
• Also different species in different places .
Factors distribution
influencing
• :
-
Nutrients -
Skin
shedding
-
Moisture -
Fluid osmolarity
-
Temperature
-
Potential inhibitors
-
pH
•
Largest numbers of bacteria tend to be found in regions
with most apocrine sweat glands .
Body External
-
Internal organs are
generally free of microorganisms
•
.
In this context
•
digestive / urinary
etc .
tracts counts as outside the
body .
Surface tissue has lots of
microorganisms
•
.
•
Collectively the microbial community associated with an
organism is called it microbiome .
Distribution of human microbiome
Some are found outside the
body skin ,
nails hair ,
, eyes) others inside
Types of Microbes
•
Most species
of microbe in
the human microbiome are bacteria .
•
These from birth onwards
colonise .
The population over time
changes
•
.
•
Early colonisers are commensal bacteria .
•
Normally mutualistic / symbiotic relationship with the host :
-
Access to nutrients
-
Defence
-
Multiple factors influence early colonisers .
•
However , occasionally there can be infections .
•
Opportunistic organism which can cause problems for the host .
• Some examples may be long-term incubators .
Microbial adhesion and attack
Healthy ( intact) skin to most bacterial attacks
acts reliable barrier
•
as a .
However to the surface of the skin
microbes will adhere
many
•
.
Some bacteria are able to attach to surfaces and
grow (biofilms)
•
.
•
Often involves attachment of bacterial adhesions to the glycoproteins of
the skin surface .
External Microbial Flora -
Skin
skin the distribution
However although bacteria colonise much
of the is not even
•
can ,
.
•
certain areas have more microbes than others .
• Also different species in different places .
Factors distribution
influencing
• :
-
Nutrients -
Skin
shedding
-
Moisture -
Fluid osmolarity
-
Temperature
-
Potential inhibitors
-
pH
•
Largest numbers of bacteria tend to be found in regions
with most apocrine sweat glands .
