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Sem 2: Microbiology > Week 10 > Flashcards

Week 10 Flashcards

1
Q

What root-soil microbial interactions are critical for plant health?

A

Rhizosphere colonisation
Endosphere colonisation
Sol disease complexes

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2
Q

What is the rhizosphere?

A

The area surrounding and influenced by plant roots mediated by excudates

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3
Q

What is the rhizoplane?

A

The surface of the roots where bacteria live

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4
Q

What is the endosphere?

A

The interior of the roots where root soil interactions can occur

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5
Q

What are examples bacterial plant pathogens?

A

Liberbacter spp - citrus greening
Black rot - Xanthomonas campestric
Streptomyces scabies - common scab
Psedomonas syringae - tomato speck
Ralstonia solanacearum - wilt

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6
Q

What is an overview of Erwinia bacteria?

A

Cause rot (black leg) by secreting cell wall degradng bacterial enzymes

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7
Q

What is an overview of Wilt pathogens?

A

Blot Xylem and Pholem with biofilms suffocating the plant

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8
Q

What is an overview of wheat-take all decline?

A

Gaeumannomyces graminis causes roots system to regress
First year starts and gets worse every year, sudden drop off in disease severity in year 4 and every year after
Antibiotics produced by Pseudomonas fluorescens which kill the fungi, takes 4 years for amount of bacteria to grow to a sufficient level

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9
Q

What are PGPR and examples?

A

Plant growth promoting rhizobacteria which can be fertilisers and pesticides
Bacillus thuringiensis spores (insecticide, New Zealand)
Pseudomonas fluorescens A506 U.S. - treatment for fire-blight (Erwinia amylovora)

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10
Q

How much carbon fixed by plants are secreted into the soils?

A

~20%

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11
Q

What is the function of plants releasing carbon into soil?

A

Attract biocontrol PGPR
Prime immune response, provide nutrients and hormones, fertilise soils and fight of pathogens

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12
Q

What are examples of biofertilisation?

A

Rhizobium, Bradyrhizobium - Symbiotic nitrogen fixation
Azospirillum, Azotobacter - Free-living N2 fixers
Pantoea agglomerans
Microbacterium laevaniformans, Pseudomonas putida etc. Inorganic phosphate -> Organic acids

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13
Q

What is an overview of legume symbiosis by rhizobia?

A

Legumes form symbiotic relationships with nitrogen-fixing soil bacteria called rhizobia.
The result of this symbiosis is to form nodules on the plant root
In these nodules, bacteria convert nitrogen into ammonia that can be used by the plant

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14
Q

How root nodules form in legume rhizobia symbiosis?

A

Rhizobium release Nod factors causing plant root hair to curl in response
The curling encloses the plant root hair forming an infection thread
Bacteria colonise infection thread
Plant forms a root nodule around bacteria, which become bacterioids which can only ever live in the nodule fixing nitrogen in return for food

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15
Q

What is an overview of Arbuscular mycorrhizal fungi symbiotic relationship?

A

Arbuscles (increased surface area for interaction between plant and fungus)
Symbioses with AMF occur in more than 90% of plants
Allows for exchange of nutrients eg nitogen and phosphate and sugars (phosphate fertiliser prevents this because of high level of plants)

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16
Q

What is an overview of bacteria influencing plant hormones?

A

Auxins: Plant growth hormones, promote plant growth and development (root growth and fruit ripening) eg Indole-3-Acetic Acid (IAA)

Azotobacter, Pseudomonas sp. among others:
Encode genes for production and degradation of IAA
Also produce other plant growth factors - Gibberellins and Cytokinins

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17
Q

What is an example of bacteria producing plant growth hormones?

A

Bacillus, Enterobacter, certain Pseudomonas sp.:
Produce enzymes for the synthesis of 2-3-butanediol, acetoin (plant growth promoting metabolites)

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18
Q

What is an example of bacteria producing cofactors?

A

Pyrrolquinoline quinone (PQQ)
antioxidant,
antifungal activity
ISR induction

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19
Q

What is an overview of bacteria influencing plant stess control?

A

Aminocyclopropane-1-carboxylic acid (ACC) a precursor to ethylene
Stress -> Ethylene -> inhibition of root elongation, accelerated abscission, aging and senescence
Bacteria produce ACC deaminase -> converts ACC to NH3 and alpha-ketobutyrate

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20
Q

What does ACC deaminase protect plants against?

A

Polyaromatic hydrocarbons
Phytopathogenic bacteria (can make them more vulnerable)
Heavy metals such as Ca2+ and Ni2+
Drought
Salt

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21
Q

What is an overview of siderophores?

A

Iron/other metal-binding small (500-1000 Da) molecules
Facilitate metal ion scavenging

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22
Q

What is an overview of Pyoverdin?

A

Fe3+ scavenger, high affinity for iron
Can inhibit pathogen growth through iron limitation - antibiotic use

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23
Q

What is an overview Pyochelin?

A

Weak Fe3+, strong Cu2+ and Zn2+ chelator
Can function as an antifungal antibiotic

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24
Q

What is an overview of cyclic lipopeptides?

A

Antropatic molecule - hydrophobic fatty tail and hydrophilic peptide head
Function as powerful surfactants
Antibiotic activity due to membrane solubilisation as membrane of fungi lyse open and die
Original function of bacterial surface swarming

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25
Q

What is an overview of Phenazines?

A

Inhibit electron transport in pathogenic species
Catalyse the formation of hydroxyl radicals in combination with ferripyochelin - damage lipids and macromolecules
Contribute to oxygen shuttling in microoxic environments
May contribute to iron mobilization in soil

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26
Q

What is the structure of phenazines?

A

Ring carbon structure with nitrogen

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27
Q

What is an example of antibiotics produced by bacteria?

A

2,4-DAPG - phloroglucinol - Causes damage to oomycete membranes, e.g. Pythium spp. Toxic to plants at high concentrations. Involved in the take-all supression
Pyrrolnitrin – inhibits fungal respiratory chains
HCN – releases cyanide ions, metalloenzyme inhibitor

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28
Q

What is an overview of secreted chitinases?

A

Produced by certain Pseudomonas spp.
Hydrolyse fungal cell walls - biocontrol
Secreted by type 2 secretion system

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29
Q

What is an overview of secreted Pectate lyase?

A

Digest plant material (e.g. Potatoes)

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30
Q

What is an overview of secreted AHL Lactonases?

A

Degrade QS molecules
Interfere with Quorum Sensing of other bugs - prevent bacteria from thinkng they are at a high enough concentration to pathogenise

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31
Q

What is an overview of secreted bacteriocins?

A

Diverse, narrow-spectrum proteinaceous toxins
Prevent other bacteria taking your niche

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32
Q

How do plants influence soil microbes differently?

A

Gas Chromatography Mass Spectroscopy (GC/MS) of extracted barley root exudates shows that different varieties (Chevalier and Tipple have different exudate profiles
This is done to manipulate environment as different chemicals result in different bacterial growth seen in A.thaliana with chemicals influencing species that can grow

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33
Q

What is stable isotope probing?

A

Substrate of interest enriched with a heavy stable isotope (e.g. C13) that is consumed by the organisms under investigation.
DNA incorporating the heavy C13 isotope is separated from naturally occurring DNA (containing C12) by isopycnic centrifugation seen which bacteria live through plant excodates eg pseudomonas live heavily off plant excodates

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34
Q

What are biodiversity of rhizosphere?

A

The rhizosphere (soil influenced by the root) is much richer in bacteria than the surrounding bulk soil due to root exudates eg Amino acids, organic acids adn sugars

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35
Q

What causes root systems to diverse?

A

Bacteria are attracted to root exudates by chemotaxis
They attach and form microcolonies
Biofilm forms - small communities

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36
Q

What is the gnotobiotic model?

A

50 mL Falcon tube –> Vermiculite/Sand/Glass beads
(abiotic structured environment) –> Plant rooting solution
(defined, carbon-free mix of minerals, ± nitrogen) –> Plant seedling –> Bacteria under investigation

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37
Q

What are the applications of model environments?

A

Examining impact of bacterial colonisation on plant growth/behaviour
Total RNA/protein extraction – transcription/proteome changes during colonisation (RNAseq/qRT-PCR and mass spectroscopy) the impact bacteria have on growth

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38
Q

How can bacterial-plant interactions be tracted?

A

Luminescent/fluorescent markers. Inserted genetically
Can be used to track bacterial distribution, or as biosensors for metabolite secretion from plant roots

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39
Q

How can bacteria be identified?

A

16S RNA
Housekeeping genes, such as DNA gyrase, recA, mutL provide more accurate assessment of within species diversity and relatedness

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40
Q

What are the advantages of metagenomics?

A

Unbiased
Comprehensive
Identifies pathways and gene functions in an environment
Can be used to assemble unculturable genomes

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41
Q

What are the disadvantages of metagenomics?

A

Expensive
Data processing is intensive

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42
Q

How can bacterial colonies be cultured?

A

Colony picking from agar plates,
Limiting dilution in liquid media in 96-well plates
Microbial cell sorting (FACS)

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43
Q

What is the advantage of iChip?

A

Raises percentage of culturable soil bacteria from <1% to around 50%

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44
Q

Whats an overview of insects and microrganisms?

A

Every plant and animal lives in close association with millions of micro-organisms
The average human is host to 39 trillion microbes – around 1.3 bacteria for every human cell
This association also holds true for insects – they span the whole range from beneficiaries, commensals to parasites
Most live in the insect gut – a stable & nutrient rich environment

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45
Q

What is an overview of Wolbachia?

A

Wolbachia is a member of the Alphaproteobacteria Class – its members are Gram-negative, intracellular and include a diverse range of members such as Rhizobium a symbiont of plants and the ancestors of mitochondria.
Wolbachia cant exist on its own, and survives by infecting arthropod hosts including insects, spiders and crustaceans.

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46
Q

How wide spread is Wolbachia?

A

Wolbachia is found in ∼66% of arthropod species
Insects comprise ~ 85% of all animal species
Wolbachia may be the most common endosymbiont in the world.

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47
Q

How is Wolbachia so successful?

A

Wolbachia can be be horizontally transmitted between arthropods, but it also has an amazing evolutionary trick, it actually enters individual cells, growing and manipulating the cells’ components. It is then able to be transmitted vertically from parents to offspring, passing into the cytoplasm of eggs so that insects are born infected.

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48
Q

How does Wolbachia make sure it gets into each newly divided cell?

A

When a cell divides, it creates a structure called a spindle that helps make sure each of the new cells gets the right number of chromosomes.Wolbachiais able to latch on to the spindle, and make sure the new cells also get a healthy dose of bacteria as well.

49
Q

How does Wolbachia make sure it is present for vertical transmission?

A

By concentrating itself in the gonads and finding its way into every developing oocyte of an organism it can make sure that it infects all of its offspring – the result – this developing embryo is full of Wolbachia from the very first cell – the bacteria can now make sure that it manipulates its spread into the gonads of this organism as they develop.
Concentration in the prosterior of the embryo

50
Q

What is required for the vertical transmission of Wolbachia?

A

In spite of all their tricks - Wolbachiacan’t be transmitted via sperm – the cells are simply too small to fit enough bacteria inside for successful infection of an egg, male inheritance therefore is a ‘dead-end’
The bacterium can only be inherited from mother to offspring so an infected male would appear to have no way of helping the reproduction of Wolbachia.

51
Q

How have Wolbachia evolved to alter the reproductive method of hosts?

A

Feminisation
Parthogenesis
Male killing
Cytoplasmic incompatibility

52
Q

What is an overview of feminisation by Wolbachia?

A

Occurs mainly in isopods and some insects
Importantly for these species genetic males develop as fully fertile females.

53
Q

What is an overview of feminisation by Wolbachia? in Insects

A

In insects, Wolbachia seems to be able to manipulate the sex determination pathway more directly. It’s not clear what the bacteria do, but if the insects are given antibiotics part way through development, females will develop normally, but males that started out developing as females will end up being somewhere awkwardly between the two sexes.

54
Q

What is an overview of feminisation in Wolbachia in Isopods?

A

In some isopods, the bacteria head for the organ that produces male sex hormones and destroy it, ensuring the embryo develops as a female

55
Q

What is an overview of Parthogenesis caused by Wolbachia?

A

Occurs in the hymenoptera in these species of insects
Males only have one set of chromosomes instead of two. Males develop from unfertilized eggs, while fertilized ones get two sets of chromosomes, and end up producing females. Wolbachia gets rid of the males entirely.
Infected females produce unfertilized eggs that do one of two things: copy their chromosomes without dividing, or undergo a normal cell division that’s followed by the fusion of the two nuclei that result.
In either case, the animal winds up with two sets of chromosomes and goes on to develop as a normal, if infected, female.

56
Q

What is an overview of male killing?

A

In many species it can be fatal to develop as a sex that doesn’t match your chromosome type – so male killing is thought to occur in those species where feminization is not possible. Ulitmately having the same effect

57
Q

What is an overview of cytoplasmic incompatibility?

A

The most common method of reproductive manipulation. Here when an infected male’s sperm merge with uninfected eggs, the first cell division of the new embryo fails—the male’s chromosomes never fully condense, and don’t divide properly. In contrast, when they merge with infected eggs, everything works fine

58
Q

What are the outcomes for cytoplasmic incompatibility?

A

Uninfected M x Uninfected F = Alive Uninfected offspring
Uninfected M x Infected F = Alive Infected offspiring
Infected M x Uninfected F = Dead children
Infected M x Infected F = Alive infected offspring

59
Q

What is an overview of the genetics of the Wolbachia poison?

A

Most such toxin–antidote systems in Bacteria studied have simple two-gene operon structures.
And in Wolbachia this also appears to be the case –
Genetic transformation with the cidA/cidB operon into Drosophila produced the full range of reproductive effects expected from CI

60
Q

What is an overview of the Cl gene mechanism?

A

Co-expression of cidA/cidB produces healthy individuals – those expressing only cidB do not survive. The researchers hypothesise that only cidB is capable of entering sperm – if it fuses with a Wolbachia infected egg – then it will develop normally – if not then without cidA rescue the embryo will not survive

61
Q

How was the genetics of the Cl gene identified?

A

Identification of the genes/mechanisms for CI is difficult.
Cannot be cultured outside of insect hosts, makes them intractable for genetic engineering
Progress made with whole genome sequencing and comparative genomics with non-parasitic strains
Analysis of proteins in sperm
Identified the cidA cidB complex

62
Q

What are the outcomes of the Cl gene?

A

Single expression of cidA or cidB on their own produce no effect
Males expressing cidA/cidB were sterile
Females expressing cidA/cidB were fertile
Female expression of cidA in ovaries can ‘rescue’ sterile male

63
Q

What does the poison of CidB do?

A

CidB causes post-fertilisation embryonic defects
Paternal nuclear envelope breakdown is delayed
Male pronuclear DNA replication is incomplete
Nuclear division fails
Late prophase, during the first division of the apposed female and male pronuclei, and accrue through mitosis

64
Q

How was speciation being driven by Wolbachia poison?

A

Poisons only have effective antidotes with females of the same strain therefore driving speciation as matings with different poison antidotes will led to embryo death

65
Q

What is an example of an insect that doesnt naturally have wolbachia?

A

Aedes aegypti

66
Q

What is an overview of the impact Aedes aegypti has on people?

A

TheAedes aegyptimosquito is the primary vector of dengue. The virus is transmitted to humans through the bites of infected female mosquitoes and vice versa. After virus incubation for 4–10 days, an infected mosquito is capable of transmitting the virus for the rest of its life.
Aedes control measures – cannot use bednets
Insecticides – pyrethroids – almost totally immune
No competent vaccine

67
Q

How does Wolbachia potentially impact the outbreak of other pathogens?

A

Wolbachia infection interferes with other pathogens
Oral infection with Wolbachia reduces the amount of dengue virus in mosquito saliva
No-one knows how this competitive exclusion occurs

68
Q

What are ways Wolbachia can potentially help reduce the spread of dengue fever?

A

Population supression - release Wolbachia infected mosquito males they will result in dead embryos therefore population collapse
Population replacement - release males and female mosquitos that are infected and they will replace non infected natives. The Wolbachia will supress the bacteria

69
Q

What is an example of Wolbachia being an drive in evolution?

A

Nasonia giraulti & Nasonia vitripennis
Two closely related parasitoid wasps
Cannot produce fertile offspring

70
Q

What is an example of Male killing by Wolbachia?

A

Hypolimnas bolina
Found across Asia and Australasia
Infected with strain wBol1 – male killer
Only 1% of population is male

71
Q

What is the male killing mechanism used by Wolbachia?

A

Downregulation of Masc preventing the alternative splicing of genes in Wolbachia infected males
Leads to failure of dosage compensation & male death

72
Q

How have blue moon butterfly responded to Wolbachia?

A

2005 a suppressor gene was evolved by an as yet unknown mechanism in female blue moons on the island of Savaii (purple), which made their male offspring resistant toWolbachia
The survival of the fittest, the few resistant males mated far and wide, and because the suppressor gene was a dominant trait, resistant males proliferated

73
Q

How has this resistant gene impacted population demographic of blue moon butterflies?

A

From being almost all-female, the population went on to become an equal mix of the sexes in less than a year
Savaii Island
2001 and 2005 on Upolu, another Samoan island, showed a similar shift in the sex ratio during the intervening 4 years, but no one caught it in action because it occurred so quickly

74
Q

Why do responses to Wolbachia male killing evolve quickly?

A

Fast evolutionary responses to extreme population pressures are probably fairly routine in nature, given thatWolbachiais just one of many sex ratio distorters

75
Q

How was wBol1 introgression demonstrated in blue moon butterflies?

A

the phenotype of fourwBol1 isolates collected from Moorea following crosses to males from Southeast Asia.
Compared to control crosses where the samewBol1 isolate was crossed with males from within their native population.
When infected Moorean females were mated to Thai or Philippine males, creating a nuclear background that was 50% Southeast Asian/50% Moorean, the females produced significant numbers of sons: male killing did not occur
Backcrossing reduced sex ratio show genetic dilution

76
Q

What is hidden deficiency?

A

The wrong mix of gut bacteria, not just starvation, could contribute to severe malnutrition

77
Q

What is kwashiorkor?

A

Severe protein malnutrition
In Malawi alone there are 10s of thousands of children have this condition with 15% fatal cases
Gut bacteria can affect absorption of iron zinc and vitamins

78
Q

What is the amount of bacteria in and why that many for stomach?

A

~10^3/g
Gastric acidity kills most bacteria

79
Q

What is the amount of bacteria in and why that many for small intestine?

A

10^4 to 10^6
Bile secretions
Input from pancreas
Rapid transit time of contents

80
Q

What is the amount of bacteria in and why that many for large intestine?

A

~10^11
Slow movement of contents
Constant pH and substrate availability
Long term colonisation and growth of bacteria

81
Q

What is an overview of the complexity of the gut microbiome?

A

Include Gram +ve, Gram -ve bacteria, archaeabacteria
Also present are yeast fungi (Mycobiome)
The gut also contains viruses (Virome)
The Bacteriome constitutes >99% of the microbiome, hence most studies are focused on gut bacteria (100 billion per g stool)

82
Q

What is an overview of the gut virome?

A

Human faeces contain at least 109 virus-like particles/g
The human gut virome is highly individual
The great majority of the virus particles remains unidentified
Viruses are important since many carry antibiotic resistant genes as well as virulence genes
Viruses can modulate the microbiome composition

83
Q

What is an overview of the major bacterial groups in the gut?

A

Phylum –> Examples
Firmicutes –> Lactobacillus,Clostridium, Staphylococcus, Enterococcus
Bacteroidetes –> Bacteroides, Prevotella
Proteobacteria –> Escherichia, Pseudomonas
Actinobacteria –> Bifidobacterium

84
Q

What are the main phylum of bacteria in human gut?

A

Firmicutes and Bacteroidetes make up 90% of the human gut bacteria

85
Q

What factors as a baby impact gut microbiome diversity?

A

Vaginally delivered infants microbiota is dominated by mother vaginal and faecal bacteria
C-section delievered infants microbiota is dominated by skin and bacteria from hospital environment

86
Q

What factors impact the development of gut microbiome?

A

Genetics
Ageing
Diet
Stress
Infection
Antibiotics

87
Q

What are the benefits of a healthy gut microbiome?

A

Stimulation of host immune system
Aids digestion
Production of short chain fatty acids and vitamins
Inhibition of pathogenic bacteria
Transformation of bioactive compounds
Provide fixed nitrogen to the host

88
Q

What are harmful effects of gut microbiome?

A

Production of carcinogens
Play a role in obesity and diabetes
Involvement in inflammatory diseases

89
Q

What is the mutualistic relationship provided?

A

Microbiome provide health benefits Including vitamins and short chain fatty acids
We provide microbiome a comfortable home with free food and water and constant temperature

90
Q

Why have gut microbiome changed perception of human?

A

Humans are superorganisms whose metabolism represents an amalgamation of microbial and human attributes

91
Q

What is the similarity between human gut microbiomes?

A

> 50% of all humans share 75 species
90% of all humans share 57 species
However at functional level there is more similarity between individuals

92
Q

How can microbiome be used as a medicine?

A

Microbiome can be altered and manipulated towards a more healthy outcome

93
Q

What are an overview of things microbiome has impacted health and disease?

A

Pathogen exclusion
Brain development
Obesity (help reduce or gain weight)
Inflammatory bowel disease

94
Q

What are causes for obesity?

A

High caloric intake
Genetic predisposition
Microbial metabolism

95
Q

How have mice been shown to have an microbiome when different weights?

A

Obese mice have 50% fewer Bacteroidetes than lean mice and reverse for Firmicutes

96
Q

How did they come up with eviedence for gut microbiome impacting weight?

A

Mice grown in germ free facility - one group was conventionalised
Feed on western diet and weight measured
Exposed group gained weight much quickier

97
Q

What was an overview of a microbiota transplant study?

A

Colonization of germ-free wild-type C mice with a caecal microbiota harvested from obese donors results in a significantly greater percentage increase in total body fat than colonization with a microbiota from lean donors

98
Q

How did they test for gur microbiome linked to obesity?

A

Physical traits like obesity and leanness can be “transmitted”
to mice, by inoculating the rodents with human gut microbes
4 twin pairs
Fed Low fat, high fibre diet –> mouse from obese twin agined weight compared to mice from lean staying lean
But this effect was diet dependent

99
Q

What neurological systems are linked to gut microbacteria?

A

Anxiety
Depression
Sensitivity to pain
Serotonin production
Autism
Parkinson’s Disease
Alzheimer’s Disease

100
Q

What is the history of gut impacting mind?

A

More than 100 years ago it was stated that ‘our gut governs our state of mind’
Our knowledge of Gut Microbiome –Brain interactions is derived from animal studies including germ free mice.
‘The microbiome may provide new class of ‘psychobiotics for treatment of anxiety, depression and other mood disorders

101
Q

What is an example of gut brain axis?

A

Faecal microbiota transplant can alter personality behaviour in mice
The recipient mice would take up personality of the donor
The daring mice would become apprehensive
The timid mice would become more exploratory
=>the microbial interactions with brain could induce
anxiety and mood orders

102
Q

How did they show microbiome impact on aging?

A

We performed FMT from old mice to young adult mice and as control young mice to young mice
FMT from aged donors led to impaired spatial learning and memory in young adult recipients

103
Q

How microbiome transplant impact symptoms of Parkinson’s disease?

A

Remarkably, colonization of αSyn-overexpressing mice with microbiota from PD-affected patients enhances physical impairments compared to microbiota transplants from healthy human donors
PD mice with healthy faeces symptoms stayed the same

104
Q

Why does our gut have a mind of its own?

A

The enteric nervous system has over 100 million neurons
Your gut produces more serotonin than the brain
The gut bacteria can interact with both ENS and CNS

105
Q

What methods can we use to manipulate or restore the gut microbiome?

A

Bacteriophages/ antimicrobial that target specific bacteria or groups of bacteria
Diet (HMO, Resistant starch)
Faecal Microbiota Transplant (Intestinal Microbiota Transfer )

106
Q

What are the problems caused by Clostridium difficille?

A

A superbug-major cause of hospital acquired infections (community)
Spores can persist in the hospital environment: hands, floor, clothing, bedding
Produces toxins
Possible food borne pathogen
UK approx. 20,000 cases of CDI
Cost to NHS £500 million

107
Q

What symptoms are caused by Clostridium difficle?

A

Mild – severe diarrhoea
Abdominal pain
Fever
Severe case: Bowel inflamamtion (1500 deaths in UK)

108
Q

How are most at risk from Clostridium difficle infection?

A

Elderly patients who have taken broad spectrum antibiotics and Immunocompromised patients are at most risk (over 80% of CDI infection reported in people over 65 )
Clear association between disruption of normal gut bacteria by antibiotic and risk of C. difficile infection

109
Q

What is the current treatment of Clostridium difficle?

A

Currently treatable by metronidazole or oral vancomycin but relapse can occur (20-30%)
Potential risk of antibiotic resistance

110
Q

When was the first faecal transplant?

A

In 4th century AD , a Chinese Physian Ge Hong prescribed a drink (yellow soup) made from human faeces to treat food poisoning

111
Q

What is the histroy of Clostridium difficle faecal transplants?

A

First performed in 1958 on 4 patients with severe diarrhoea-all recovered within 48h
More than 200 sporadic case studies have been reported
Recently a number of large clinical trials have proven the efficacy of FMT for treatment of CDI

112
Q

What thins need to be screened for faecal matter transplant?

A

Healthy adult aged 20-40
Risk of infectious agents (eg HIV,Hepatitis and Salmonella)
Gastrointestinal comorbidity (IBS and cancers)
Intake of antibiotics
Travel to area with risk of diarrheal diseases

113
Q

What is the process faecal matter treatment?

A

The patient stops taking antibiotics
Patient is given enema to empty the bowls
Nasojejunal (NJ) tube is inserted through the nose by a gastroenterologist
On the day fresh faecal slurry is prepared at QIB
Transported to hospital and delivered to the patient via NJ tube (or via colonoscopy)
The FMT procedure takes only 20 minutes

114
Q

What is an overview of Faecal matter transplant in Norwich?

A

So far we have performed FMT procedure has 92%
success rate
Mechanism of the exclusion process to develop knowledge improvement in FMT
Analysis of the microbiome structure and function during the FMT

115
Q

What is an example of a Faecal matter transplant going wrong in Norwich?

A

Increase in Proteobacteria numbers
Case was a chronic drinker so carried on drinking making problem worse

116
Q

What are the advantages of using faecal matter treatment Clostridium difficle?

A

Cheap (£800 compared to more than £9000 for antibiotics)
High sucess rate
Easy to administer
Reduce risk of antibiotic resistance
Safe

117
Q

What are the disadvantages of using faecal matter treatment Clostridium difficle?

A

Risk of transferring unknown pathogens
Public acceptance
Long-term impact of the foreign microbiome still unknown

118
Q

What are future Faecal matter transplants?

A

Frozen donor faecal material
Freeze dried donor faecal Capsules
Defined mix of gut bacteria instead of whole faecal microbiome

119
Q

What are examples were faecal matter transplants are being used as a cure?

A

Obesity
Type II diabetes
Cancer
HIV
Depression
IBS

Sem 2: Microbiology (12 decks)

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