Lecture 3: maurice Flashcards
1
Q
humans are made up of what
A
-eukaryotes
-bacteria
-archaeabacteria
-viruses
-parasites
2
Q
what is commensalism
A
one organism benefits and the other is unaffected
3
Q
what is mutualism
A
both organisms benefit
4
Q
what is parasitm
A
one organism benefits at the expense of the other
5
Q
true or false: interactions between microbes and humans can fall anywhere on the symbiosis spectrum between beneficial and neutral
A
false it is beteween beneficial and harmful
6
Q
genome: who’s there. what is the tool?
A
amplicon sequencing/16 s rDNA sequencing
7
Q
genome: what can happen. what is the tool?
A
metagenomics/shotgun sequencing
8
Q
transcriptome: what is happening/what are they doing: what is the tool?
A
metatranscriptomics
9
Q
proteome: what makes it happen/how does it happen?: what is the tool
A
metaproteomics
10
Q
metabolome: what has and is still happening?: what is the tool
A
metabolomics
11
Q
how many phyla exist
A
more than 5o
12
Q
the human microbiota is dominated by how many phyla
A
3-5
13
Q
true or false: microbial communities are site specific
A
true
14
Q
70% of total microbiome is in the….
A
colon…..
15
Q
which bacteria dominate the stomach
A
-lactobacillus
-veillonella
-helicobacter
16
Q
True or false: microbiota composition is highly variable between individuals, the functional gene profiles are similar
A
true
17
Q
Oral and fecal communities analyzed by
A
16S rna seq
18
Q
Bacteroidota formely known as
A
Bacteroidetes
19
Q
how many species in Bacteroidota
A
70000
20
Q
Most common genera are….
A
Bacteroides, Prevotella, Porphyromonas,
and Xilanibacter
21
Q
what is the shape of the Bacteroidota
A
-gram -, anaerobic and rod shaped bacteria
22
Q
which bacteria is known to degrade a variety of complex glycans (polysaccharide utilization loci, starch utilization system)
A
Bacteroidota
23
Q
what is the most gram - bacteria of the gut microbiota
A
Bacteroides
24
Q
true or false: bacteroides are non-flagellated and non-fimbriated bacteria
A
true
25
give the % of Bacteroides vulgatus
31%
26
give the % Bacteroides thetaiotaomicron
12%
27
give the % Bacteroides fragilis
5%
28
Bacillota is formely known as the...
Firmicutes
29
is Bacillota gram + or -
mostly gram +
30
is Bacillota spore forming
yeah
31
are Bacillota anaerobe
nah they are obligate anaerobes
32
which species does Bacillota contain
Clostridium
Ruminococcus
Lactococcus
Lactobacillus
Eubacterium
Roseburia (butyrate-producing)
Faecalibacterium (butyrateproducing)
Veillonella (Gram-negative).
33
Pseudomonadota (form. Proteobacteria) in clude what...
Escherichia and Desulfovibrio (sulfate-reducing bacteria)
34
Actinomycetota (form. Actinobacteria): includes .....
Collinsella species and Bifidobacterium species (probiotics)
35
Verrucomicrobiota (form. Verrucomicrobia): includes....
the species Akkermansia muciniphila, specialized in mucus degradation
36
Main Functions of the Human Microbiome
ü Colonization resistance.
ü Production of vitamins.
ü Metabolism of xenobiotics.
ü Generation of metabolites.
ü Digestion of dietary fibers and generation of shortchain fatty acids.
ü Development of the immune system.
37
Bacterial metabolite production
ü Dietary phosphatidylcholine is hydrolyzed in the intestine by lipases to generate choline.
ü In the colon, the microbial choline utilization (cut) gene cluster is responsible for the formation of trimethylamine (TMA).
ü TMA is absorbed and oxydized in the liver into TMA N-oxide (TMAO), which is linked to higher risk of cardiovascular disease.
ü The cut gene cluster was identified in 20 members of the human gut microbiota, including members of the Bacillota, Pseudomonadota and Actinomycetota phyla.
38
Primary bile acids (e.g. cholic acid) are synthesized in the....
liver from cholesterol and excreted in bile
39
some of the primary bile acids the large intestine, where several species of....
Bacillota (e.g. Clostridial species from cluster XI, Clostridium scindens and Clostridium hylemonae) generate secondary bile acid using the bai genes
40
These secondary bile acids (e.g. deoxycholic acid) inhibit the growth of....
C. difficile, but were shown to mediate tumor development in a mouse model of
liver cancer
41
The gut microbiota degrades indigestible dietary....
carbohydrates from plants (pectin, cellulose, xilan, and starch)
42
Bacterial metabolism of plant carbohydrates generates...
short-chain fatty acids (acetate, propionate and butyrate) that account for over 10% of our daily calories
43
name microbiota scfas
-acetate
-propionate
-butyrate
44
Short chain fatty acids (SCFAs) are the fermentation end products of...
dietary carbohydrates
45
what is the concentration of scfa's
can reach up to 100 mM in the distal colon
46
Although all SCFAs influence colonic health, .... appears to have important specific functions.
butyrate
47
what is the role of butyrate
-acts as an energy source for enterocytes
-Butyrate inhibits histone deacetylases (HDAC), leading to increased histone acetylation and epigenetic modification of gene expression.
-Butyrate induces TGF-b secretion by epithelial cells
-stimulates dendritic cells and macrophages to produce IL-10 and retinoic acids
48
Butyrate-producing bacteria are widely distributed in the .... class
Clostridia
49
butyrate inhibits what?
histone deacetylases (HDAC), leading to increased histone acetylation and epigenetic modification of gene expression.
50
Butyrate and niacin bind ....
GPR109a on epithelial cells to trigger production of the cytokine IL-18.
51
Low-fiber diet promotes
expansion of....
colonic mucus-degrading bacteria (Akkermansia muciniphila)
52
Low-fiber diet increases the susceptibility of mice to
colitis caused by the enteric pathogen citrobacter rodentium
53
Bacteriocins produced by the microbiota
Consist of lantibiotics, thiopeptides, microcins,
54
true or false: bacteriocins are toxic for a specific set of bacterial species, excluding the producer
true
55
Mutacin 1140 is one of the 4 lantibiotics produced by.....
Streptococcus
mutans, active against other Streptococci
56
This mutacin undergoes post-translational modifications. Eleven genes are required for its biosynthesis
mutacin 1140
57
Disease can result from loss of ..
beneficial functions or new maladapted functions.
58
what can cause ibs, psoriasis and acne
microbial imbalance: dysbiosis
59
The vagus nerve, which connects the
CNS to the ENS, has both ... and
... neurons
afferent and efferent
60
Production of bacterial metabolites that access the bloodstream and cross the BBB can directly regulate
neurological functions (e.g. SCFAs and
neurotransmitters).
61
Immune cells and cytokines, which cross the BBB, can regulate
neurological functions, including thev hypothalamic-pituitary-adrenal axis (HPA)
62
which neurotransmitters does bacillus produce?
Dopamine, norepinephrine
63
which neurotransmitters does Bifidobacterium produce?
GABA (gamma-aminobutyric acid)
64
which neurotransmitters does Enterococcus produce?
serotonin
65
which neurotransmitters does Escherichia produce?
Norepinephrine, serotonin
66
which neurotransmitters does Lactobacillus produce?
Acetylcholine, GABA
67
which neurotransmitters does Streptococcus produce?
Serotonin
68
ASD is a neurodevelopmental disease diagnosed by
behavior impairments, deficits in language and social interactions
69
true or false: people with asd have gastrointestibnal probles
yeah
altered GI mobility and increased gut permeabilityy
70
Gut microbial dysbiosis is often observed in individuals with....
ASD
71
Large epidemiological studies linked maternal infection to increased
autism risk in the kid
72
WHAT is maternal immune activation
-mouse model: Pregnant females are treated with poly(I:C) to mimic viral infection.
-resulted in TLR3 activation and inflammation.
-offspring showed some symptoms of ASD (increased gut permeability and behavior impairments
73
MIA offspring had lower levels of .....
bacteroides fragilis
74
True or false: Feeding B. fragilis to the mice induced ASD symptoms
false it reversed the symptoms
75
MIA offspring also displayed an altered profile of serum
MIA offspring also displayed an altered
profile of serum metabolites with
increased levels of the metabolite 4-
ethylphenylsulfate (4EPS).
76
true or false: injection of 4EPS into normal mice caused the same behavioral problems
true
77
4eps is most likely a ... metabolite since gf mice don't produce it
bacterial
78
ü 4EPS is related to p-cresol, a tyrosine ...
metabolite found in urine of children
with ASD.
79
Maternal high-fat diet (MHFD)
induces.....
behavioral alretarions inb kids
80
MHFD causes alterations in....
in gut microbiota, reduction of oxytocin production, and deficient
synaptic plasticity
81
ü Presence of Lactobacillus reuteri
was reduced by ...fold in the
MHFD offspring gut microbiota
>9
82
L. reuteri treatment restores
oxytocin levels,... and ....
synaptic plasticity and social behaviors
83
name types of IBD in their respective spots
ü Crohn’s disease (mainly ileum).
ü Ulcerative colitis (colon).
ü Multifactorial diseases, with known
genetic component (NOD2)
84
what are the changes in microbiota composition in ibd
increase Bacteroides, adherent-invasive E. coli (AIEC), Helicobacter hepaticus,
85
Overall a decrease in gut microbial diversity and an ...... in the
numbers of pathobionts are observed
increase
86
true or false: IL-10-/- SPF mice are susceptible to IBD ad why
true
Susceptible germ-free IL-10-/- mice do not develop IBD
87
true or false: Susceptible IL-10-/- mice that lack TLRs or MYD88 do not develop IBD
true
88
what is important for the devlopment of tbd
Recognition of commensal bacteria by the innate immune system
89
what is: Faecalibacterium prausnitzii
-butyrate-producing Gram-positive
bacterium part of the Bacillota phylum
90
whichis: One of the most abundant bacterium in the human gut microbiota representing up to 5% of the total bacterial population
Faecalibacterium prausnitzii
91
Oral administration of live F. prausnitzii or culture supernatants .... the severity of trinitrobenzenesulfonic acid (TNBS)-induced colitis in mice
reduced
92
what could be used as a probiotic to prevent IB?
Together with Bacteroides fragilis and other butyrate-producing bacteria, F.
prausnitzii
93
Probiotic colonization is ....c
site-specific
94
Probiotics colonization is ...
person-specific`
95
Probiotic colonization is predictable by.....
host features (pathways associated with anti-bacterial defense, antigen presentation, etc
96
which is the second mpst common cancer
colorectal
97
Specific species of the gut microbiota have been linked to CRC:
* Streptococcus gallolyticus
* Enterotoxigenic Bacteroides fragilis.
* Colibactin-producing Escherichia coli.
* Fusobacterium nucleatum (Fn).
98
Fn is.... detected in stool. However, it is ..... in colorectal cancer tissues
rarely and abundant
99
what does fn do
ü Fn adheres to and invades intestinal cells through its FadA surface adhesin.
ü FadA binds to the EC5 domain of E-cadherin and activates β-catenin signaling.
100
what does fada do.
ü Fn adheres to and invades intestinal cells through its FadA surface adhesin.
ü FadA binds to the EC5 domain of E-cadherin and activates β-catenin signaling
101
what does fap2 adhesin do
ü Fn adheres to and invades intestinal cells through its FadA surface adhesin.
ü FadA binds to the EC5 domain of E-cadherin and activates β-catenin signaling
102
103
104
true or falce: ü Gal-GalNAc is highly expressed in adenomas and adenocarcinomas, but not in normal tissues.
true: This explains the abundance of F.
nucleatum in malignant tissues
105
ü Fn was abundant in CRC tissues in
patients with.....
recurrence post chemotherapy
106
true or false: fn decreased crc resistance tio chemi
false: it promoted
107
Fn .... the autophagy
pathway in a TLR4-dependent
manner and, in turn, ....
chemotherapy-induced apoptosis
Fn activated the autophagy
pathway in a TLR4-dependent
manner and, in turn, inhibited
chemotherapy-induced apoptosis
108
