Human microbiome part 1

Question 1

Human genome HOW MANY GENES DO WE HAVE

Answer 1

23,000

Question 2

What do we think we know about the microbiome

Answer 2

everyone has their own microbiome, even identical twins

this is acquired in early life, can be different in environments and can persist for years

Question 3

Host–microbiota interactions

Answer 3

Microbiome and their host constitute a highly integrated system
holobiont (benefits come from microbiome)

Undergoes dynamic changes through time as it processes and responds to signals from the environment.

Commensal actively modulate development, nutrient absorption, and disease onset

Question 4

Human Microbiome Project

Answer 4

we use molecular techniques because less than 1% of bacteria are culturable

Question 5

The 16s rRNA Gene
what does it code for?
why it it used?

Answer 5

it codes for a ribosomal RNA
it’s used as a bar code for microbial identification

Why?
Universal
Conserved
Long enough to discriminate between species
Databases available.

Question 6

The Integrative Human Microbiome Project - 10 year initiative divided into 2 phases

Answer 6

HMP1 focused on mapping microbial communities from various body sites (e.g., gut, skin, mouth) in healthy adults, with some disease-focused projects.

HMP2 studied how the microbiome and host biology change over time in specific conditions—pregnancy, inflammatory bowel disease, and prediabetes—using advanced multi-omic analyses (e.g., gene expression, metabolites, proteins, immune markers).

Question 7

Normal Microbiota

Answer 7

Transient flora may be present for days, weeks, or months.
Not permanent
Form of contamination
Potential infection risk
Removed by washing

Resident microbiota permanently colonise the host.
Not removed by washing

Question 8

HOW LONG CAN BACTERIA STAY IN BODY?

RESIDENT AND TRANSIENT

Answer 8

resident = is when there is a fixed type of microorganism found in a given area at a given time

Transient = nonpathogenic or potentially pathogenic microorganisms that inhibit area for a short period

Question 9

Normal microbiota

Answer 9

Range of microorganisms
Evolves throughout life
In a dynamic but stable balance
Balance can be disrupted

Question 10

normal microbiota depends on

Answer 10

health
age
diet
climate conditions

Question 11

dominant phyla - how many are they JUST NAME THEM

Answer 11

4 dominant phyla

1) actinobacteria
2) bacteriodetes
3) firmicutes
4) proteobacteria

Question 12

dominant phyla NAME AND EXAMPLES

Answer 12

1) actinobacteria - gram positive
bifdiobacterium, mycobacterium, corynebacterum

2) bacteroidetes - gram negative
bacteriodes and provotella

3) firmicutes - gram positive
staphylococcus, streptococcus and

4) proteobacteria - gram negative which is e coli