Microbial Interactions Flashcards
Populations
assemblages of similar organisms
Communities
mixtures of different populations
Ecosystems
self-regulating biological communities and their physical environment
Symbioses
relationships among organisms in an ecosystem
Ectosymbiont
located on the surface of another larger organism
Consortium
physical contact between different organisms of similar size
biofilm
Endosymbiont
located within another organism
Ecto/endosymbiosis
lives both inside and outside of another organism
Mutualism
- two organisms that cannot live without one another
- Metabolically dependent on each other
Buchnera aphidicola and aphids
Rumen microbes and Ruminants
Cooperation
- both organisms benefit from living with each other but can also exist apart from each other
- syntrophism
- Chromatium provides organic matter and Desulfovibrio provides CO2 and H2S
Syntrophism
growth of one organism depends on or is improved by growth factors or nutrients from another organism growing nearby
Commensalism
- one organism benefits and the other is neither harmed nor helped
- can also be syntrophic
- Nitrosomonas and Nitrobacter
- E.coli and Bacteriodes
Predation
- one organism gains and the other is harmed
- predator engulfs or attacks the prey
- some protists, bacteria, fungi
Parasitism
- one organism gains (parasite) and the other is harmed (host)
- slower process than predation
- viruses, fungi, lichens
Amensalism
- negative impact of one organism on another based on release of a specific compounds
- antibiotics by bacteria and fungi
- bacteriocins
- organic acids during fermentation
Competition
two organisms try to acquire or use the same resource
- one dominates and prevents the other from getting the substrate
- two share the resource, and both survive at lower population levels
Microbes role in ecosystem
- primary producer
- decomposer
- impact plant function
- food for other organisms
- change amount of minerals in soluble and gas form
