"Microbiomes: Microbial Systems in & Around Us"

What is a microbiome?

The community of microbes and all their genes living in a specific environment.

Where are microbiomes located?

Microbes are everywhere. (Gut, soil, ocean, skin)

What are the five types of microbes?

Bacteria, Archaea, Protists, Fungi, Viruses.

Why are microbiomes considered complex systems?

They behave like ecosystems due to species interactions, environmental influences, community changes over time, and functional redundancy.

What is culture-free microbiology?

A method of studying entire microbial communities without culturing, using DNA.

What does rRNA (16S) sequencing identify?

Major microbial groups and their relative abundance.

What is the main focus of metagenomics?

To identify genes for metabolism, toxins, and resistance, revealing functional potential. Also to sequence all DNA in a sample.

What does DNA indicate in microbiome studies?

What's present in the microbial community.

What does RNA indicate in microbiome studies?

What's being actively used in the microbial community.

What do proteins and metabolites tell us?

What's actually happening in the microbial community.

In which physical systems can microbial communities exist?

Soil, oceans, freshwater, atmosphere, ice, and extreme environments.

How can microbes act as environmental sensors?

By detecting pollution and tracking harmful microbes or toxins.

What are four ways hosts acquire their microbiomes?

Birth or hatching, diet, environment, social interactions.

What are some benefits of host-microbiome associations?

Aid digestion, protect against pathogens, shape immune systems, help plants absorb nutrients.

How can microbiomes be engineered?

To improve nutrient uptake in plants, feed conversion in cattle, increase disease resistance, or increase susceptibility for research.

What connects the gut and brain?

Neural pathways, immune pathways, and hormonal pathways.

What neuroactive compounds do gut microbes produce?

Serotonin, dopamine, GABA.

What is the link between dysbiosis and mental health?

Dysbiosis is linked to depression, anxiety, and autism spectrum disorder.

How is brain-gut communication altered by stress?

Stress changes gut permeability & microbial balance.

How can gut-brain communication affect mood?

Microbial metabolites influence mood, cognition, and behavior.

What is fecal microbiota transplant (FMT)?

Transfer of healthy donor fecal material into a recipient's GI tract to restore microbial diversity.

What is a proven use of FMT?

Treatment of recurrent Clostridium difficile infection with over 90% success.

What are some experimental uses of FMT?

Major depressive disorder, anxiety, autism spectrum disorder, Parkinson's, Alzheimer's.