Microbial Nutrition Flashcards
Essential Nutrient
any substance that must be provided to an organism
Macronutrients and examples
Required in relatively large quantities and play a principal role in cell structure and metabolism
C, H, O
Micronutrients are known also as what? What are they and examples?
present in much smaller amounts and are involved in enzyme function and maintenance of protein structure
Mg, Zn, Ni
Inorganic Nutrient
An atom or simple molecule that contains a combination of atoms other than C and H found in the earth’s crust, bodies of water, and the atmosphere
Organic Nutrients
Contain C and H atoms and are the products of living things, simple organic molecules such as methane
large polymers such as carbohydrates, lipids, proteins, nucleic acids
Heterotroph
Organism that must obtain its carbon in organic form
Autotroph
organism that uses inorganic C02 as its carbon source, has the capacity to convert CO2 into organic compounds, does not depend on other living things
Phototroph
microbes that photosynthesize
Chemotroph
Microbes that gain energy from chemical compouds
Inactive Transport
Simple Diffusion is an example, moves with concentration gradient
Active Transport
Requires energy and moves against concentration gradient
Capnophiles
Microbes that like Carbon Dioxide
What can environmental factors alter in Microbes?
the function of metabolic enzymes
What are Environmental Factors?
Temp Gasses- CO2 and O pH Salt Pressure Radiation
What does the top of the bell curves represent in the Temperature of Adaptation graph?
the optimal temperature the microbe needs to reproduce the best
What temperatures do Mesophiles prefer and how could we get rid of them potentially?
Like our body temp 10-50 (38ish)
could get rid of them with a fever
Aerobes
Utilize Oxygen
Obligate Aerobe
Cannot survive without Oxygen
Microaerophiles
only need a little Oxygen
Faculative Anaerobes
don’d care if there is no Oxygen, use it when it is present
Anaerobes
Prefer no oxygen
Obligate Anaerobe
will die in the presence of Oxygen
What are the two types of associations between organisms
Symbiotic and Non-Symbiotic
What are the three types of Symbiotic Relationships microbes can have?
Mutualism
Commensalism
Parasitism
What are the two types of non-symbiotic relationships microbes can have?
Synergism
Antagonism
What is Symbiosis?
What are symbionts?
A general term to denote a situation in which two organisms live together in a close partnership
Symbionts are members of a symbiosis
What is mutualism?
organisms live in a mutually obligatory but beneficial relationship: need each other to survive
Commensalism
Where does this occur?
The interaction is obligatory for the partner called the commensal (receives the benefits), while the partner is neither harmed nor benefitted
This happens in our body, provides organisms place to live but they do not harm us or benefit us
Parasitism
A relationship in which the host organism provides the parasitic microbe with nutrients and a habitat; parasite usually harms the host to some extent
Antagonism Definition
An association between free-living species that arises when members of a community compete “At war”
What is antibiosis and in which relationship does it occur in?
Occurs in antagonism a non-symbiotic relationship;
it is the production of inhibitory compounds such as antibiotics into the surrounding environment that inhibit or destroy another microbe in the same habitat
The first microbe has a competitive advantage by increasing the space and nutrients available to it
This is common in the soil where mixed communities compete for space and food
Synergism
an interrelationship between two organisms that benefit them but is NOT necessary for survival
What does synergism accomplish?
What are some examples of this?
together the participants cooperate to produce a result that none of them could do alone; Gum disease, dental caries, and some bloodstream infections
Biofilms
Mixed communities of bacteria and other microbes that are attached to a surface and each other
Form a multilayer conglomerate of cells and intracellular material
What are the basic steps to forming a biofilm?
A pioneer colonizer attaches to a surface
Other microbes then attach to those bacteria or a polymeric sugar or protein substance secreted by the microbial colonizers
attached cells are stimulated to release chemicals as the cell population grows
Quorum Sensing
How does this work?
Microbial Communication: used by bacteria to interact with members of the same species as well as members of other species that are close by
Use chemical signals to communicate
What is the structure of the biofilm?
Large complex communities form with different physical and biological characteristics
Cannot be eradicated by traditional methods
What may we find at the bottom of a biofilm?
may have a very different pH and oxygen conditions than the surface
What are the basic steps of binary fission
One cell becomes two
parent cell enlarges
duplicates its chromosome
starts to pull its cell envelope together to the center of the cell
cell wall eventually forms a complete central septum
Turbidity
Cloudiness
A clear nutrient solution becomes turbid or cloudy as microbes grow in it
The greater the turbidity, the larger the population size
Direct cell count
measured microscopically
Coulter Counter
electronically scans a fluid as it passes through a tiny pipette
flow cytometer
words similarly to a coulter counter but can help differentiate between live and dead cells
