L10: Animal Microbiomes Flashcards
what is the complexity gradient of microbiome diversity
- Lepidoptera caterpillar gut
- Bobtail squid light organ
- Aphid bacteriocytes
- honeybee gut
- vertebrate gut
microbiome diversity - Lepidoptera caterpillar gut
no detectable resident microbiota
microbiome diversity - Bobtail squid light organ
single symbiont
microbiome diversity - Aphid bacteriocytes
- 1-2 primary symbionts
- a few microorganisms
microbiome diversity - honeybee gut
a few microorganisms
microbiome diversity - vertebrate gut
hundreds of microorganisms
what is the complexity gradient of model systems
- Hawaiian Bobtail squid
- fruit fly
- zebra fish
- mice
- humans
diversity of model systems - Hawaiian Bobtail squid
proteobacteria
diversity of model systems - fruit fly
- proteobacteria
- firmicutes
diversity of model systems - zebra fish
- proteobacteria
- fusobacteria
diversity of model systems - mice
- firmicutes
- bacteroidetes
- proteobacteria
diversity of model systems - humans
- firmicutes and bacteroidetes
- actinobacteria
examples of host-mictobiota co-adaptation mechanisms
- corals and dinoflagellates
- termites and wood decay
- crop plants and root microbiome
- cows and rumen microbiota
- lab mice and gut microbiota
host-microbiota co-adaptation - corals and dinoflagellates
carbon provision in nutrient-poor waters
host-microbiota co-adaptation - termites and wood decay
lignocellulose degredation
host-microbiota co-adaptation - crop plants and root microbiota
nutrient provisiong
host-microbiota co-adaptation - cows and rumen microbiota
nutrient metabolism
host-microbiota co-adaptation - lab mice and gut microbiota
disease modeling
define phylosymbiosis
describes a pattern of symbiotic relationships where evolutionary history of a host organism correlates with the composition of its associated microbiome
phylosymbiosis - where is it not seen
microscopic marine invertebrates
define compartmentalization
- separation of the cell interior in distinct compartments
- can also separate microbes in space
how can compartmentalization drive the evolution of symbiotic cooperation
it can allow hosts to stabilize cooperation via:
- isolates symbionts and controls their reproduction
- reward cooperative symbionts and punish non-cooperative ones
- reduce direct conflict among different symbiont strains
gut microbiota - C. elegans
- protobacteria
- bacteroidetes
- firmicutes
- actinobacteria and acidobacteria (super small)
gut microbiota - Drosophila
- firmicutes
- protobacteria
gut microbiota - Honey bee
- firmicutes
- protobacteria
- bacteroidtes (very small)
gut microbiota - fish
- has all families
1. protobacteria
2. others
3. firmicutes
4. bacteroidetes
5. acidobacteria
6. cremarchaeota
gut microbiota - mice
- firmicutes
- bacteroidetes
- protobacteria
- others
- cremarchaeota and acidobacteria (very small)
gut microbiota - humans
- has all microbes
1. firmicutes
2. bacteroidetes
3. protobacteria
4. cremarchaeota
5. acidobacteria
6. others
explain the gut microbiota diversity in animals from most to least
- mammals
- fish
- reptile
- insect
- bird
host factors influencing gut microbiome
- genotype
- phenotype
- vertical transmission
- innate immunity
- adaptive immunity
- other mechanisms
host factors influencing gut microbiome - humans
- genotype
- phenotype
- vertical transmission (expect vegetative reproduction)
- innate immunity
- adaptive immunity
- other mechanisms (except coprophagy)
host factors influencing gut microbiome - mice
- genotype
- phenotype
- vertical transmission (except vegetative reproduction)
- innate immunity
- adaptive immunity
- other mechanisms
host factors influencing gut microbiome - fish
- genotype
- phenotype
- vertical transmission (except maternal provisioning)
- innate immunity (except PGRP)
- adaptive immunity
- other mechanisms (except coprophagy)
host factors influencing gut microbiome - honey bees
- genotype
- phenotype
- vertical transmission (except female germ cells and vegetative reproduction)
- innate immunity (except NOD-like receptors)
- NO adaptive immunity
- other mechanisms
host factors influencing gut microbiome - Drosophila
- genotype
- phenotype
- NO vertical transmission
- innate immunity (except NOD-like receptors)
- NO adaptive immunity
- other mechanisms
host factors influencing gut microbiome - C. elegans
- genotype
- phenotype
- vertical transmission (only female germ cells)
- innate immunity (except PGRP and NOD-like receptors)
- NO adaptive immunity
- other mechanisms (except coprophagy)
host factors influencing gut microbiome - Hydra
- genotype
- phenotype
- vertical transmission (only vegetative reproduction)
- innate immunity (except PGRP)
- NO adaptive immunity
- NO other mechanisms
gut microbiota: diet and food levels - carnivores
- firmicutes and actinobacteria
- fusobacteria
gut microbiota: diet and food levels - omnivores
proteobacteria
gut microbiota: diet and food levels - herbivores
- firmicutes (99%)
- actinobacteria (1% - only 1 recorded)
gut microbiota: diet and food levels - from most to least diverse
- herbivore
- omnivore (balanced diversity)
- carnivores
Ant proventriculus case study - what is a proventriculus
- a valve located between the crop and midgut of insects
- blocks the enter of bacteria and particles ≥0.2 um into the mid- and hindgut
- allows the passage of dissolved nutrients
Ant proventriculus case study - explain the microbiome after the proventriculus
- the mid-, hindgut, and rectum
- has Opitutus sp. as the dominant microbe
aphid bacteriome case study - what is a bacteriocyte
they are large cells that form the building blocks of the bacteriome
aphid bacteriome case study - what is a bacteriome
- specialized organ that host endosymbiotic bacteria
- houses Buchnera spp.
aphid bacteriome case study - what microbiome colonizes the aphid gut
- facultative symbionts
- gut-associated bacteria
- bacterial pathogens
- plant associated bacteria and pathogens
aphid bacteriome case study - explain the Buchnera aphidicola bacteria
- aphid ancestor and bacteria co-diversified
- results in genome reduction
- the bacteria engages in amino acid and vitamin provisioning
- this provisioning is then maternally transmitted from bacteriocyte to progeny (children)
Hawaiian bobtail squid and Vibrio fisherii case study - what does the squid use the bacteria for
- Vibrio fisherii is contained within the Hawaiian bobtail squid’s light organ
- the bacteria produces light for the squid to camouflage
Hawaiian bobtail squid and Vibrio fisherii case study - explain the colonization process
- sterile (0 - 30 mins)
- permissive (30 - 60 mins)
- restrictive (60 - 120 mins)
- specific (past 120 mins)
Hawaiian bobtail squid and Vibrio fisherii case study: colonization process - sterile
- 0 mins: host hatches from egg
- 30 mins: the bacteria’s cilia of surface epithelia begin to beat
Hawaiian bobtail squid and Vibrio fisherii case study: colonization process - permissive
- light organs are open to small numbers of bacteria or particles < 2um
- 60 mins: host sheds mucus in response to bacterial peptidoglycan
Hawaiian bobtail squid and Vibrio fisherii case study: colonization process - restrictive
- initiation of bacterial aggregates (gram-negative bacteria)
- bacteria and particles are removed by an unknown mechanism
Hawaiian bobtail squid and Vibrio fisherii case study: colonization process - specific
- only V. fisherii
- V. fisherii aggregate above the pore and migrate to the duct before colonizing the light organ
define bacterial quorum sensing
internal form of of communication that bacteria use to coordinate group behavior
bacterial quorum sensing - define autoinducers
a chemical signal molecules that bacteria use in quorum sensing
bacterial quorum sensing - how does it define the squid-vibrio symbiosis
- at low cell density, bacteria produces autoinducers
- via quorum sensing, bacteria move close and become high in density
- high density than produces light
explain compartmentalization in corals
- mucus
- tissue
-skeleton
compartmentalization in corals - mucus
- 1st line of defense
- has its own microbiome
compartmentalization in corals - tissue
- made of the: epidermis, mesoglea, gastrodermis, and mouth
- has its own microbiome
- has coral-associated microbial aggregates (CAMAs)
- contains the phycosphere
compartmentalization in corals: tissue - CAMAs
- clusters of bacteria that form in the tissues of corals
- contains Endoziocomonas (Gammaproteobacteria)
compartmentalization in corals: CAMAs - Endoziocomonas
- E. marisrubri 6c may have the ability to home in on suitable hosts via motility and chemotaxis
- they then activate a cascade of mechanisms to evade or modulate host immune responses
compartmentalization in corals: CAMAs - Endoziocomonas benefits
- amino acid metabolism
- biosynthesis and B vitamin provisioning
- utilization of organic carbon sources by E. marisrubri 6c
compartmentalization in corals: tissues - phycosphere
- region around the Symbiodiniceae surface that is identified by the algae production of metabolites
- within the tissues and inside the symbiosome
compartmentalization in corals - skeleton
- contains: endoliths and endolithic band
- hotspot for bacterial diversity
- has its own endolithic microbiome
- has tissue and endolith nutrient exchange
compartmentalization in corals: skeleton - bacterial diversity
- has a low photosynthetically active radiation (PAR)
- has stable near-infrared radiation (NIR) that is useable by bacteriochlorophyll
compartmentalization in corals: skeleton bacterial - bacteriochlorophyll
- a photosynthetic pigment found in certain bacteria
- helps harvest light energy
compartmentalization in corals: skeleton - nutrient exchange between endoliths and coral tissue
N and C nutrient exchange is increased in unhealthy/bleached corals
compartmentalization in corals: nutrient exchange between endoliths and coral - low susceptibility to bleaching
usually has:
- greater diversity
- functional redundancy
- lower C and N assimilation (chemolithotrophy)
compartmentalization in corals: nutrient exchange between endoliths and coral - high susceptibility to bleaching
- lower diversity
- higher C and N assimilation (photoautotrophy)
- higher productivity
explain the how microbes can provide a fast-response mechanism to rapid environmental change
from long to short:
1. genetic adaptation
2. epigenetic modification
3. acclimatization
4. algal symbionts
5. bacterial community
how can we harness microbes to help organisms adapt
- microbial transfer therapy
- probiotics
microbial dynamics - healthy coral
mutualist
microbial dynamics - unhealthy coral
- opportunists
- copiotrophs
- presence of pathogens and pathobiome
microbial dynamics: unhealthy coral - copiotrophs
- organisms found in environments with abundant nutrients
- specifically carbon
microbial dynamics: unhealthy coral - pathobiome
community of microorganisms that interact with the host to cause disease