--Which non covalent interactions are most likely to be important in protein-protein interactions in aqueous environment?
--What is the driving force for proteins that are embedded in lipid membranes?
As you know, there are four main types of non-covalent interactions: ionic bonds (or electrostatic interactions), van der Waals forces, hydrogen bonds, and hydrophobic interactions.
Ionic bonds occur between charged groups and can be very strong individually. However, if there are too many of them, they can operate as repulsion forces between proteins because "like charges" (negative/negative or positive/positive) will repel each other. Therefore, although they can stabilize a protein-protein interface, they do not drive its formation. They act more as forces that govern the specificity of the interaction. Generally, if you increase the electrostatic charges on proteins, you dissociate them!
van der Waals forces are dipole-dipole interactions that are weak individually, but can sum up to quite a large force collectively. Once again, they do not drive the ...
The solution comprises of a detailed 540 word explanation of important protein-protein interactions in an aqueous environment, and the driving force for proteins that are embedded in lipid membranes.
Molecular and Cell Biology: Eukaryotic Cells and Moving Proteins and Organelles
a. How have Eukaryotic cells solved the problem of moving proteins and organelles from one part of the cell to another, faster than would occur by diffusion? And give a specific example to illustrate how a protein may be moved from part of the cell to another.
b. Describe one mechanism that ensures that proteins are moved to the appropriate place within a cell.
a. Using examples to illustrate your answer name and briefly describe four different types of non-covalent interactions that can occur between and within molecules.
b. How is a Scathard plot generated, and what measure of the inter-molecular interaction is used to determine this?
a. What are three features of a protein domain?
b. Briefly outline there attributes conferred on a protein by having multi-domain architecture. Illustrate your answer using at least two examples of multi-domain proteins.
a. Briefly describe how packaging of DNA into chromatin contributes to DNA protection, compaction and metabolism.
b. Briefly describe one factor of cellular component that contributes to the packaging of the eubacterial chromosome.
c. How is the type of DNA packaging found in Archae similar to that observed in Eukaryotes?
a. In terms of replication origins, how do the chromosomes of E. coli and S. Cerevisiae differ?
b. What is the main advantage to a cell of having a defined starting point for DNA synthesis?
a. Two post-translational modification of proteins and indicate where the modification takes place within the cell and what effect it has on the protein.
b. What is a proteasome, and what function does it have and where is it located within the cell?
c. How are proteins targeted to proteasomes?
d. How do functions of proteasomes and MHC molecules combine to contribute to immune defense?