Microbiome 8.1 Flashcards
Microbiome are composed of?
bacteria, archaea, eukarya, viruses
What is a microbiome?
a population of mirobes in an environment (which could be anywhere, skin, hair, table, apple, air, water, stomach, carpet)
What do you look at to determine if a microbiome is DIFFERENT?
Sequencing of the DNA sequence for 16S ribosomal RNA
- If they are exactly the same= same organism
- they one nucleotide is different, they are different
Over _____ of ____ are known to exist based on 16s ribosomal RNA gene sequence information
80 phyla of bacteria
**90% of the characterized bacterial species are in what 4 phyla?
Proteobacteria, Actinobacteria, Firmicutes, and Bacteroidetes
Fewer than ____ of all bacterial species have been characterized
fewer than half
~10,000 species are characterized
What is the species we know exists but cannot grow and learn about them?
Zeta-
caldisercia
elusimincrobia
gemmatimonadetes
Proteobacteria are a diverse phyla of Gram____ bacteria? found where?
negative
*several classes, some of which contain bacteria that live in or on humans
Where are the classes of proteobacteria? Which one is a main focus?
**gamma is main one
Classes: gamma, beta, alpha, zeta, epsilon, delta
Firmicutes contain?
Lactic acid producing bacteria
Firmicutes are or are not fermentative?
they ARE fermentative
In regards to air/oxygen, Firmicutes are?
aerotolerant anaerobes
Do Firmicutes produce energy through oxidative phosphorylation?
NO
Firmicutes contain what species?
Streptococcus species
Firmicutes are catalase negative or positive?
catalase negative
In regards to air/oxygen, Bacteroidetes are?
obligate anaerobes
Bacteroidetes are spore forming or non-spore forming?
non-spore forming
*thus some of them are part of the anaerobic environments of the human body
Porphyromonas gingivalis is in what phylum?
Bacteroidetes
What are the lactobacillales organisms?
Streptococcus, Lactobacillus, and Leucronostoc species
Is Porphyromonas gingivalis important for denstistry? Why or why not?
cause the development of periodontal disease
Human Microbiome Project is based on what gene?
16S ribosomal RNA gene
point of Human Microbiome Project ?
To figure out what bacteria are colonizing at different locations in and on the body and how they are different
What is a Core microbiome?
arbitrarily defined as the species that are present at a specific site in 95% or more of individuals
Secondary microbiome
Microbial species that contribute to the unique diversity of individuals at specific body sites
Dysbiosis
disruption of the normal microbiome that can lead to disease by the elimination of microbiome organisms allowing growth of inappropriate bacteria
EVERYONE has which microbiome and which one is unique: Secondary microbiome or Core microbiome?
Core microbiome= everyone has it
Secondary microbiome= UNIQUE to each person
The human microbiome begins when?
babies are “painted” with microbes as they pass through the birth canal
Passage through the birth canal helps ensure that a baby’s?
microbiome looks just like its mother’s, which may help prepare it for the outside world
Breast milk itself contains not just food for the growing baby, but food for the infants’?
microbial inhabitants, as well as its own microbiome
Nearly all of the microbiomes are harmless or perform __________, such as aiding digestion
harmless or perform beneficial functions
beneficial bacteria are called?
commensals or mutuals
T or F. One of the functions of commensal bacteria is to help the immune system mature
TRUE
Studies have found that mice raised in sterile, germ free environments have poorly developed
immune systems or dysfunctional immune systems
Microbiota means?
Community of microbes that live in and on an individual; can vary substantially between environmental sites and host niches in health and disease
**refer to the bacteria itself
Normal flora
Microbiota (=collection of micro-organisms aka microbiota)
define host and host benefits for normal flora
humans that provide a place to colonize, nutrients, and some protection from unwanted species (via immune responses)
define the benefits for hosts from normal flora
The microbes provide needed metabolic functions, stimulate innate and regulatory immunity, prevent colonization with unwanted pathogens, etc
