The Human Microbiome Flashcards
What is microbiota?
Individual microbial species in a biome - bacteria, fungi, archaea and viruses
What is the most rapidly changing field in human biology?
Human microbiome
What is the aim of the human microbiome project?
To characterise microbial communities found at multiple human body sites and to look for correlations between changes in the microbiome and human health
How long was the HMP?
5 years
When did the HMP start?
2008
How much did the HMP cost?
$150 million
What methods were used by the HMP?
Culture independent methods of microbial community characterisation (16S and meta genomics) as well as whole genome sequencing of individual bacterial species
What did the HMP sample?
The whole body but had emphasis on oral, skin, vaginal, gut and nasal/lung
How many microbial species in the human microbiome?
10,000
How many bacterial species in the gut?
500-1000
What did the HMP aim to develop?
A reference set of microbial genome sequences and to perform preliminary characterisation of the humans microbiome. Also new technologies and tools for computational analysis
What did the HMP aim to explore?
The relationship between disease and changes in the human microbiome
What did the human microbiome aim to establish?
A resource repository (to share information)
What did the HMP aim to study?
The ethical, legal and social implications of human microbiome research
What were the 2 main results of the HMP?
Different sites have different microbes and your microbiome is not my microbiome
What is meant by different sites have different microbes?
Strong niche specialisation both within and among individuals
What is meant by your microbiome is not my microbiome?
Diversity and abundance of each habitats signature microbes vary widely even among healthy subjects
What did HMP document?
81-99% of the genera, enzyme families and community configurations occupied by the healthy western microbiome
What can change?
The community but the function doesn’t (as much)
What was observed in the results of the HMP?
Variations in both pathways and microbes changes with clinical metadata along ethnic/racial differences
How many bacterial groups exist?
More than 92
How many archael groups exist?
26
How many micro flora dominate human microbial communities?
4
Which 4 microbes dominate human microbial communities?
Firmicutes, bacteriodetes, actinobacteria and proteobacteria
How many human associated microbes have eluded colourisation so far?
Estimated 20-80%
What did different sites have?
Different conditions and the differences in microbes reflect this
What portion of decal biomass is bacterial cells?
50%
What are functional foods?
Foods claimed to have a health promoting or disease preventing property beyond the basic function of supplying nutrients
What are probiotics?
Living organisms (fermented foods-yoghurt)
What are the most common microbes used as probiotics?
Lactic acid bacteria (LAB) and bifidobacteria
What do probiotics do?
Survive transit through stomach and duodenum
What are the potential benefits of probiotics?
Chronic intestinal inflammatory diseases, treatment of pathogen induced diarrhoea and urogenital infections
What are probiotics?
An ingredient that beneficially nourishes the good bacteria already in the large bowel or colon
What do prebiotic do?
Stimulate the growth of probiotics
What do the prebiotic fibres do?
They are not themselves digested by the body, instead, the fibres act as a fertiliser to promote the growth of many of the good bacteria in the gut. These, in turn, provide many digestive and general health benefits
What do some prebiotic target?
Bifidobacteria and lactobacilli (probiotics stimulate the growth of probiotics)
How are probiotics obtained?
Mostly from a type of carbohydrate fibre called an oligosaccharide
What are good sources of prebiotic?
Whole grains, bananas, onions, garlic, honey and artichokes
What is used when communities in the human gut go away?
Fecal matter transplants
What is fecal matter transplantation used for?
Multiple recurrences of clostridium difficult infection
