L30 Flashcards
What does penicillin target
The transpeptidase that forms the cross links in the peptidoglycan cell wall of bacteria
What do bacteria provide us with
Vitamins
Ratio of bacteria to our mammalian cells
1:1
What are the goals of the microbiome project?
to understand the different types of bacteria on our skin, changes in the microbiome and changes in our health
Microbiome
The complete collection of microorganisms and genes within a particular envionrment
Microbiota
Individual species in the biome - bacteria, fungi, archaea and viruses
Imp parts of the heirarchy
Domain. genus, class, strain
How many bacteria and archaeal phyla
92 bac and 26 archaeal
Goals of the HMT
- To develop a reference set of
microbial genome sequences and
to perform preliminary
characterization of the human
microbiome - To explore the relationship
between disease and changes in
the human microbiome - To develop new technologies and
tools for computational analysis - To establish a resource repository
- To study the ethical, legal, and
social implications of human
microbiome research
How many species of microbes in the Human microbiome
10,000
How many species found in the gut
500-1000
Strong niche specialisation
Microbes found in the mouth are specialised to live in that envir
What is different about the microbiomes from person to person
Each person has their own unique microbiome
Correlation between strains and function
Different strains in different individuals but the metabolic function is consistent across individuals i.e the functions of the strains are similar
What does the microbiome do for us?
a) Preventing pathogens from being successful
b) Block colonization niches
c) Competing for nutrients
d) Modifying environment to change virulence factor expression
e) Making environment actively hostile: Producing bacteroicins
(antimicrobial) & short chain fatty acids (SCFA)
f) Lowering pH
g) Cause host to thicken mucus layer
h) Cause host to upregulate antimicrobial peptides (defensin, IgA)
i) Primes host neutrophils and macrophages
Which bacteria protect us from pathogens
Commensal bacteria as pathogens cant compete
What do broad spec antibiotics do?
They destroy all bacteria - good and bad and our commensal bacteria may be affected
Which bacteria dominate our body
*Firmicutes
* Bacteroidetes
* Actinobacteria
* Proteobacteria
We all have the same bacteria groups but different strains
Why are there different organisms throughout the gut
Due to differences in pH, O2 levels which selects for different types of bacteria
SCFAs
Short chain fatty acids, they regulate our and the bacteria’s metabolism and ward off pathogens
How do the microbes in our gut help us?
Break down the indigestible stuff into endpros –> used by other bacteria to extract every last bit of E –> Endpros
What can the microbiome influence
v synthesise vitamins including:
v B Vitamins: B1, B6, B5 [pantothenic acid], B7 [biotin], B9 [folic acid], B12
[cobalamin]
v Vitamin K
v modulate the immune response
v alter drug delivery
What is a functional food
Does something besides provide energy that help our microbiome to combat disease
What are probiotics
Live organisms eg LAB and Bifidobacteria that survive transit through the stomach and duodenum and could influence the microflora in the gut, mostly placebo effect because our microbiome is very specific so can outside bacteria influence
What are prebiotics
Nutrients for the probiotics, fertiliser for them
