"Production
PHB is produced by feeding bacteria on a nutrient-rich diet until large colonies of the bacteria begin
to form. At this point, glucose is withdrawn from the diet, and the bacteria will automatically secrete
PHB as an energy store, similar to the body fat of humans.
One bacterium which produces PHB is Alcaligenes eutrophus. In recent times, genetic engineering
techniques have enabled scientists to locate the specific gene responsible for the secretion of PHB,
and then to transfer this to bacterium such as Escherichia coli, more commonly known as E. Coli.
Advantages to using E. Coli generally centre around the fact that scientists are more familiar with
the bacterium, and as such, find it much easier to work with, providing a faster production rate."
Can someone confirm if this information is correct. This is from the Student's Guide to HSC Chemistry.
Because in the Ahmad Shah Revised, Edited and perfected notes ---> they talk about Biopol production (but the start is the same thing) and this is what he wrote:
"In industrial production, A. Eutrophus is grown in an environment favourable to its growth to create a very large population of bacteria (such as high nitrates, phosphates and other nutrients).
When a sufficiently large population has been produced, the environment is changed to one that is high in glucose, high in valeric acid and low in nitrogen.
This unnatural high energy dieted environment induces the production of the polymer by the bacterium; the polymer is actually a natural fat storage material, created by the A Eutrophus in adverse conditions. This process always reduces the colonies numbers greatly.
So which is it. Is glucose added or removed?
PHB is produced by feeding bacteria on a nutrient-rich diet until large colonies of the bacteria begin
to form. At this point, glucose is withdrawn from the diet, and the bacteria will automatically secrete
PHB as an energy store, similar to the body fat of humans.
One bacterium which produces PHB is Alcaligenes eutrophus. In recent times, genetic engineering
techniques have enabled scientists to locate the specific gene responsible for the secretion of PHB,
and then to transfer this to bacterium such as Escherichia coli, more commonly known as E. Coli.
Advantages to using E. Coli generally centre around the fact that scientists are more familiar with
the bacterium, and as such, find it much easier to work with, providing a faster production rate."
Can someone confirm if this information is correct. This is from the Student's Guide to HSC Chemistry.
Because in the Ahmad Shah Revised, Edited and perfected notes ---> they talk about Biopol production (but the start is the same thing) and this is what he wrote:
"In industrial production, A. Eutrophus is grown in an environment favourable to its growth to create a very large population of bacteria (such as high nitrates, phosphates and other nutrients).
When a sufficiently large population has been produced, the environment is changed to one that is high in glucose, high in valeric acid and low in nitrogen.
This unnatural high energy dieted environment induces the production of the polymer by the bacterium; the polymer is actually a natural fat storage material, created by the A Eutrophus in adverse conditions. This process always reduces the colonies numbers greatly.
So which is it. Is glucose added or removed?
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i read many other places that nitrogen is excluded from the diet not glucose.