Microbiome Flashcards
Define Human Microbiota (-ome)
Collection of bacteria, archaea, and eukaryotic microbes usually coloring the body
True or false: There are half of the microbial cells vs human cells within the body
False: there are approximately equal numbers of microbial and human cells within human body
~____ trillion human and microbial cells in body (write in scientific notation)
~30 trillion
(3x10^13)
Bacteria weigh ~___-___ lbs
~ 2-5 lbs
Establishment of microbiome
Previously believed rebar fetus grew in ______ environment
What is the first stool passed by baby before first feeding called?
Placenta may have its own micro biome
Sterile environment
Meconium (contains bacteria)
True or false: Babies delivered by C section may have different bacteria compared to vaginally delivered
True
Delivery by C-section may be associated with increase risk for what 4 things?
Obesity
Celiac disease
Asthma
Allergies
Breast Mille contains ________ __________ (HMOs) that feed specific bacteria
Name the species:
Indigestible oligosaccharides
Bifidobacterium longum infantis
There is evidence linked between microbiome and asthma
Give examples:
– Breast-fed babies have less asthma than formula-fed babies
– Vaginal birth babies have less asthma than C-section babies
– Antibiotic use in babies’ first year linked to increased risk of
asthma
Babies that lack four specific bacteria are much more likely to develop asthma. What are they?
Four microbes: Lachnospira, Veillonella, Faecalibacterium, Rothia
Resident microbial community is dynamic - changes in what?
Age, diet, hormonal state, antibiotic use, and stress
~ _____ billion to ____ trillion (10^12) bacteria on skin
~100 billion to 1 trillion
Describe three types of Microhabitats
- Oily (behind ear, between eyebrows)
- moist (belly button between toes, armpits bends)
-Dry (forearm)
What species is a normal resident on skin?
Staphylococcus epidermidis
Curibacterium acnes
gram (+) or (-)?
Digests _____
Causes what?
Gram positive
Digests sebum
Causes acne
Nose - protects against respiratory pathogen
What are two pathogens found in your nose?
And what do they do?
Staphylococcus epidermidis (Forms biofilm)
Staphylococcus aureus (controlled by protease produced by S. epidermidis, if not controlled can become pathogenic and cause infection)
Mouth
What is the fungus that is an opportunistic that can cause oral infection (thrush)?
Candida albicans
Streptococcus mutant
Gram (+) or (-)?
Facultative _____
Forms a ____ on the hard enamel surfaces of teeth
If gums become inflamed S mutants can enter bloodstream and cause what?
Gram (+)
Facultative anaerobe
Forms biofilm
Causes infection, including endocarditis
S mutants is significant cause of tooth decay Sugar (sucrose) fermentation produces _____ ____. Which does what to pH in mouth and did what to teeth?
Fluoride inhibits _____ synthesis and can inhibit ______ growth
Produces lactic acid
Lovers pH in mouth and demineralization of teeth
Inhibits ATP synthesis and microbial growth
GI tract
_______ _______ produces enzymes urease, hydrolysis urea, produces _____ and neutralizes stomach acid
Helicobacter pylori
Produces ammonia
_______ _______ which causes cholera, is very sensitive to ____ pH and cannot survive passage through stomach.
Vibrio cholerae
Helicobacter pylori
Gram (+) or (-)?
Gram negative: proteobacteria
Vibrio cholerae
Produces what?
Reservoir?
Mode of transmission?
Treatment?
Prevention?
Cholerae toxin that causes host cells to secrete electrolytes and water
Humans
Indirect (vehicle): contaminated water
Treatment: rehydration and doxycycline
Prevention: clean water
Intestines
Estimated __-___ trillion bacteria in intestines
~__-__ million unique bacterial genes
10-30 trillion
~ 8-9 million
Bacteria in intestines do good things, such as: protect you from pathogenic bacteria
Digest food (what bacteria does this?)
And produces vitals (what bacteria produces vitamin b12?)
Bactericides thetaiotamicron digest food
E. Coli produces vitamin b12
Bacteriodes
Major inhabitants of the human _______
Ferment a wide range of _____ indigestible by humans
-break down potential ______ in plant food/products
Can cause what if they escape intestines?
Human intestine
Sugars
Potential toxins
Cause infections if they escape
Benefits of bacteria
Break down ______ that humans cannot digest
Produces ____
Train _____ system
Regulate development of ____
Carbohydrates
Produces vitamins
Train immune system
Regulate development of gut
Benefits of bacteria
Protects against pathogenic bacteria
Produces ______ (toxins produces by bacteria to inhibit growth)
Alter local _____ and produce acid
Compete for resources and location
Bacteriocins
Alter Local habitat
E. Cool produces bacteriocins that can kill what two species?
Shigella and salmonella
What is the vaginal ph?
~4
Hygiene hypothesis suggests that changes in human behavior has led to food of diversity in the human microbiota, such as:
Overuse of antimicrobials
Dietary changes
Cesarean birth
Absence of breastfeeding
Loss of diversity impacts homeostasis
