esr473/notes/regulation-two-comp.html
Regulation of new cell composition depends on relative amounts of key metabolites. Gene expression responds to over and underproducing components. the flux of metabolites is also controlled at the level of enzmes and pathway activities (not just total). this leads to two steps in the response of the cells to a change in environmental conditions and resources. Cells control the flux of metabolites at the level of enzymes.
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| starting condition | active+inactive RuBisCO |
| short term response: activation of enzymes time scale = minutes |
all active RuBisCO |
| intermediate response: producing mRNA time scale = hours (for fast growing algae) |
new enzyme mRNA |
| intermediate response: synthesis of new proteins time scale = many hours |
increased total RuBisCO enzyme mRNA signal decays |
| growth response: adaptation of protein content time scale = days |
more active RuBisCO with some inactive |