Survival strategies
17 important questions on Survival strategies
How does efficient survival strategies work?
They have very good sensors that can monitor the changes in nutrients, pH, temperature and pressure. When a change is monitored there is a regulating system that can act on these changes.
What happens when there is a stress imposed on the micro-organism?
Substrate binds to receptor and activates response.
This is smart because if the stress is not there there does not have to be a response.
super fast process
What is a danger for food safety on adaptive responses of micro-organism?
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Why is listeria often chosen as a model organism?
- Because of its ability to tolerate adverse conditions such as low Aw and low temperature
- Insight in listeria stress adaptation in terms of its improved survival in foods (because it is one of the most dangerous)
- Designing safety or extended shelf-life of minimally processed food (if you know what you need to do to kill thisone it will probably also work for others)
Why does lysteria monocytogenes have a high mortality rate?
What are the 2 temperature proteins made by the sigma factor?
Cold shock: Maintaining the overall conformation of messenger proteins. (due to low temperature more enhanced hydrophobic interactions which may cause difference in conformation of rna and proteins) cold shock proteins protect rna and proteins form this.
Heat shock: They repair proteins damaged by the stresses. Or of they are to damaged they cut them away and make new ones. Because damaged proteins may inhibid cell functioning.
What is a adaptive responce?
What is cross protection?
How does the sigma B factor work?
What does Listieria do to survive low water activity?
These salts are glycine betaine and carnitine
How are the transporters involved in osmoadaptation of L. momocytogenes called?
BetL: for betaine
OpuC: for carnitine
Becasue 2 poms use ATP they can work against the stream and cope with low water activity
What is the function of osmo-adaptation?
- balancing osmotic disturbance
- stabilize enzymes
- stabilize the membrane
- protect cells during freezing
- stimulate low temperature adaptation
How can listeria deal with acid/low pH?
Is there a difference in glutamate decaroxylase between stains of listeria?
How does low temperature adaptation go?
They can protect the RNA from deformation and therefore the ribosomes are able to transcribe proteins.
A micro-organism can have different types of cold shock proteins.
How can listeria with a mutant in the chaperon protein survive in higher stress conditions?
This makes that the bacteria did not have to be in a extreme condition in order to make it. It already has the ClpP and therefore is more resistant.
Why does the original nor resistance listeria have flagella and the new type not?
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