Oral Ecology Flashcards
microbe
tiny living organism, such as bacterium, fungus, protozoan, or virus
microbiome
collectively all the microbes in the human body; a community of microbes
living in synergy or antagonism
changes related to changes in health and disease
biofilm
a community of microbes that live together on a surface
factors which the oral cavity a good incubator for microbes
moist
warm
fed frequently
usually stable - can change due to diet etc
how do bacterial cells outnumber body cells
Bacterial cells outnumber your body cells 10:1 and comprise up to 4-6 lbs of your body mass
We are a vehicle for microorganisms
- They have greater control of us
Live in synergy, they influence us
what does a microbiome include
A microbiome includes all the microorganisms in a particular ecosystem.
The term is sometimes used to describe the community of microorganisms in a particular place.
(If not multiple – gingival crevice, dorsal of tongue, cavity/carious lesion, denture)
Sometimes it is used to describe the total/sum of the genetic material of the microorganisms in a particular ecosystem.
- Genetic material has many sources – inflammatory cells, host cells etc
2 meanings of microbiome
The term is sometimes used to describe the community of microorganisms in a particular place.
(If not multiple – gingival crevice, dorsal of tongue, cavity/carious lesion, denture)
Sometimes it is used to describe the total/sum of the genetic material of the microorganisms in a particular ecosystem.
- Genetic material has many sources – inflammatory cells, host cells etc
what does microorganisms and humans/animals being holobiant imply
Synergy between microorganism plants and simple animals
Evolve convergently not divergently
- Everchanging
2 states microbes can be to the human body
native
introduced
introduced microbes are
Suddenly arriving at a new residence in the body
- With time and age
how does the GIT microbial community assemble
From delivery: The gut flora of vaginally-delivered babies differs from babies delivered by C-section
- The vaginal microbial community of pregnant women contains bacteria involved in digesting milk (Lactobacillus)
From feeding: The nature of the flora colonizing the intestines changes depending on whether the baby is bottle- or breast-fed
The oral cavity, skin, gastrointestinal tract, respiratory, and urogenital system all continue to be colonized as contact with other humans continues
what influences how MO species disperse/established in the body
Species traits can influence the probability of both dispersal/establishment, as well as how they fare in competition and other species interactions.
trait of lactobacillus that favours it
Excludes many pathogens as it metabolises sugar to acid
- Almost protective
what is the main influence on the microbial community in the gut
diet
is the microbial environment same across the body
no
All different compositions
- important changes in compositions at different locations on body
- able to stratify populations
5 benefits of normal flora
Synthesize and excrete vitamins
- Vitamin K and Vitamin B12
Prevent colonization by pathogens
- competing for attachment sites or for essential nutrients
May antagonize other bacteria
- the production of substances which inhibit or kill non-indigenous species (nonspecific fatty acids, peroxides, bacteriocins).
Stimulate the development of certain tissues
- i.e., intestines, certain lymphatic tissues, capillary density
- benefit to immune system and physiology
- —no microorganisms can lead to malnourishment and being sensitive to external stresses
Stimulate the production of cross-reactive antibodies.
- Low levels of antibodies produced against components of the normal flora are known to cross react with certain related pathogens, and thereby prevent infection or invasion.
- Tolerance to immune stimulus is dictated by type you have