Microorganisms found across all three domains of life Bacteria Archaea Eukarya The Biology of Microorganisms Eukarya Although we typically think of members of the domain Eukarya as being large multicelled organisms there are in fact many eukaryotic microbes ID: 784936
Download The PPT/PDF document "The Human Microbiome The Biology of Mic..." is the property of its rightful owner. Permission is granted to download and print the materials on this web site for personal, non-commercial use only, and to display it on your personal computer provided you do not modify the materials and that you retain all copyright notices contained in the materials. By downloading content from our website, you accept the terms of this agreement.
Slide1
The Human
Microbiome
Slide2The Biology of Microorganisms
Microorganisms found across all three domains of life
Bacteria
ArchaeaEukarya
Slide3The Biology of Microorganisms-
Eukarya
Although we typically think of members of the domain
Eukarya as being large, multi-celled organisms, there are in fact many eukaryotic microbes
Eukaryotic cells have membrane bound structures called organelles
Ex. nucleus, mitochondria, chloroplasts
Mitochondria and chloroplasts may have originally been symbiotic bacteriaMicroorganisms: protists, algae, fungi
Slide4The Biology of Microorganisms – Bacteria
Bacteria +
archaea
= prokaryotes Most prokaryotes lack membrane bound organellesMost prokaryotes and a have circular chromosome (and occasionally small circular plasmids)
Prokaryotes use cytoplasmic membrane to generate energy
Bacteria have diverse metabolism:
Respire on oxygen, nitrate, sulfate, iron and many other compoundsCan obtain energy from organic carbon, nitrite, ammonia, hydrogen, methane, sulfur, etc.
Some are photosynthetic
Slide5The Biology of Microorganisms-
Archaea
Many are extremophiles pHTemperature
Salinity
Pressure
Some live under non-extreme conditionsStructurally different from bacteria:Cell membrane lipid contentCell wall structureFlagella structure
Archaea
are found in extreme places such as: (a) swamps and sewage plants (b) salt lakes (c) deep sea hydrothermal vents (d) hot springs
Slide6The Biology of Microorganisms - Viruses
Not living organisms but often still labeled as “microorganisms”
Have their own genome
Unable to synthesize their own proteins, replicate themselves independently and have no metabolic capabilities
Require the machinery of the cell that they are infecting to replicate themselves.
Slide7The Human Microbiome
For the past 500 million years animals have hosted microbes in and on their bodies
Microbes are often harmless and even cooperative
Microbes help us in defending against pathogens and help boost our metabolism. In return we provide them with nutrients and a home
Human
microbiome
– collection of microbes within and on the human bodyHuman microbiome varies across different body sites and from person to person
Slide8Questions
Describe the differences in metabolism and structure between bacteria,
archaea
, and eukaryotes Why are viruses not considered to be living organisms?
Why do you think that the human
microbiome
varies across different body sites?
Slide9The Human Microbiome
Project- History
Human Genome Project (HGP) complete in 2006
Led to advances in DNA sequencing technologies and
bioinformatic
methods
Human Microbiome
Project (HMP) grew from the HGP and began in 2007
Main funding from the National Institutes of Health
Slide10The Human Microbiome
Project - Goals
Develop a set of reference microbial genome sequences from the human
microbiome and begin the preliminary
characterzation
of the healthy human
microbiome Explore the relationship between disease and changes in the human microbiome
Develop new tools and technology to analyze all the DNA sequences
Create a place to store and share data with others
Create a place to store physical samples of DNA and microorganisms that can be accessed by other researchers
Consider the ethical, legal, and social implications of the research
Slide11The Human Microbiome
Project – Methods
Challenges with sequencing the human
microbiomeThousands of different species of microorganisms Many of these bacteria are unable to be grown in a laboratory
Slide12The Human Microbiome
Project – Methods
16S
rRNA gene sequencing The 16S rRNA is a component of the 30S subunit of prokaryotic ribosomes
Gene encoding the 16S
rRNA
is often used in phylogenetic studies in order to identify bacteria present in a community and to map their relationship to each other
Slide13The Human Microbiome
Project – Methods
16S
rRNA
sequencing
Slide14The Human Microbiome
Project – Methods
16S
rRNA gene sequencing provides a good estimate of who is there; however, this data does not tell scientists about what the microbes could be doing inside our bodies
In order to get a better idea of how these microbes live their lives inside our bodies, scientists had to turn to
metagenomic
sequencing.Metagenomics- the study of the total DNA extracted from an environmental sample
Slide15The Human Microbiome
Project – Methods
Metagenomics
Slide16Map of the Human Microbiome
Sites of the body with their own unique
microbiomes SkinMouth
Gastrointestinal tract
Urogenital tract
Slide17Questions
1. What are the two methods that scientists use to explore the human
microbiome
? What information do these methods give us?2.If you were a scientist working on the Human Microbiome Project, what questions would you try to address about the human
microbiome
?
Slide18What Your Microbes do for You
Fighting off pathogens
-
Lactobacillus reuteri RC-14 produces one or more molecules that is capable of inhibiting toxin synthesis by
Staphylococcus
aureus
.Iron absorption - studies on mice that that lack gut microbes suggest that there is a link between the gut microbiota
and the development of iron deficiency.
Vitamin production –
Gut microbes produce vitamin B12, vitamin B6, vitamin B5, vitamin B3, biotin,
tetrahydrofolate
, and vitamin K.
Antooxidant
production
- Indole-3-propionic acid is a powerful antioxidant found in the human body. A group of GI tract bacteria have been implicated in the transformation of
indole
to indole-3-propionic acid.
Slide19Questions
Why do you think that people take probiotics? Do you think that they are beneficial?
What might happen to a person who has taken antibiotics?
Slide20Your Microbiome
and Your Health
Studies focus on observing how the microbial communities of healthy and diseased individuals differ and how the
microbiome fluctuates over the course of a disease so that a "disease microbiome
" can be established for different complex conditions
For many complex diseases it is believed that a community of microorganisms, rather than one pathogen, may lead to the development of disease
Slide21Your Microbiome
and Your Health
Diseases associated with an unhealthy
microbiome Psoriasis
Skin ulcers
Inflammatory bowel disease
ObesityAnxiety and depressionColorectal cancer
Slide22Your Microbiome
and Your Health
Microbes may effect how your body metabolizes
drugesExample: paracetamol and health supplement metabolism
Slide23Questions
How do scientists figure out if disease development is triggered by the
microbiome
?What are some ways that doctors could treat diseases that are known to be associated with an unhealthy human
microbiome
?
Slide24Personalized Medicine
Personalized medicine
- a branch of healthcare that utilizes a patient's unique clinical, genomic, historical, and environmental information to inform both the treatment of disease in that individual but also to maintain a state of wellness. The goal of personalized medicine is to optimize healthcare for each individual rather than the average person.
Slide25Personalized medicine
Slide26Personalized medicine
The bacterial communities within you play a major role in your body's day-to-day functioning (or malfunctioning, in some cases).
The information known about the interactions between the
microbiome and disease development and drug metabolism can help doctors personalize healthcare to not to an individual but also their microbes.
Slide27Questions
How does personalized medicine differ from medical practice currently?
How can a person’s
microbiome information be used to personalize their healthcare?