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About BabcockHall

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    bioorganic chemistry
  1. ammonium generation

    Do you suppose that generation of ammonia and pH could be related? Please explain.
  2. How to avoid coconut oil from freezing?

    I am going on memory, but coconut oil may be high in saturated fatty acyl residues. If so, I wonder whether adding a small amount of an oil that has a greater degree of unsaturated fatty acyl groups would help.
  3. need help- esterification

    Which hydroxyl group do you want to react? I don't know but I wonder if you would need to protect the other one. What mole ratio of DMAP are you using?
  4. Energy From Fructose

    There is controversy concerning whether or not a diet high in fructose is healthy. I cannot evaluate this question without a great deal more study, but I found a few links for those wishing to pursue the topic. Fructose metabolism in humans – what isotopic tracer studies tell us Fructose, but not glucose, impairs insulin signaling in the three major insulin-sensitive tissues Fructose Consumption in the Development of Obesity and the Effects of Different Protocols of Physical Exercise on the Hepatic Metabolism
  5. Energy From Fructose

    In muscles and kidneys, hexokinase converts fructose into fructose 6-phosphate and enters into the hexose phosphate pool at this point; it can be converted into fructose 1, 6-bisphosphate (the first committed step of glycolysis) or be converted into glucose 6-phosphate. However, in liver fructokinase converts fructose into fructose 1-phosphate, which is cleaved into glyceraldehyde and dihydroxyacetone phosphate (DHAP) by an aldolase. DHAP is converted into glyceraldehyde 3-phosphate GAP by triosephosphate isomerase and enters into glycolysis in this way. Glyceraldehyde is separately phosphorylated to GAP and continues through glycolysis.
  6. Energy From Fructose

    Fructose enters into glycolysis differently from glucose; it comes in later. IIRC there is an aldolase that is distinct from the aldolase that we associate with glycolysis, but the details escape me at the moment. Therefore, the regulatory controls which govern early glycolytic enzymes such as hexokinase and phosphofructokinase-1 are bypassed. Although glucose 6-phosphate and fructose 6-phosphate are easily interconverted by phosphohexoseisomerase, IIRC this is not the point at which the pathway from fructose joins glycolysis.
  7. need help- esterification

    Did the double bond isomerize in a stereochemical (cis-trans) sense; did it move in a regiochemical sense; or did it do something else?
  8. need help- esterification

    Esters can be made using dicyclohexylcarbodiimide and catalytic DMAP. Another method is to use oxalyl chloride to form the acid chloride. We have used the latter method successfully in the presence of a double bond.
  9. Have you read the forum policies?
  10. Organic synthesis, please help.

    Please show us the work you have done so far. This will make it easier for us to help you.
  11. Why do we have to write so many highschool papers?

    Doing scientific research has almost no benefit to anyone unless one publishes the results, presumably in the form of a journal article. I have read many student laboratory reports, and I have read and written scientific papers. Writing well is a very difficult but very important skill to master. Part of writing clearly is thinking clearly.
  12. Bacterial Flageller

    Each E coli cell has about half a dozen flagella. They act as screw propellers. When all rotate in the same direction, the bacterial cell moves forward. When some rotate in one direction and others rotate in the opposite direction, the bacterium tumbles, and will then swim in a new direction. This is how chemotaxis occurs. The flagellum is powered by the proton motive force. I think of it as an electric motor of a sort. Other species are different in the specifics. One problem that the E. coli cell must solve is how to export the proteins and assemble the flagellum from its constituent proteins.
  13. Hydrogen Ions ? This is a link to a paper on bacteriorhodopsin, which is a light-driven proton pump. It might give you a general picture of how protons and proteins interact. Groups such as Asp85 and Asp96 transiently bind to the proton that is being actively transported. This protein was put into artificial vesicles with ATP synthase. Light cause bR to create a proton gradient, which was able to drive the synthesis of ATP, an early demonstration that the Mitchell chemiosmotic hypothesis was correct. My understanding is that protons that are not bound to side-chains on a protein are frequently bound to buffering species. The concentration of free protons is small.
  14. Extinction and concentration

    Unless the starch molecule has a defined number of glucose monomers, I don't see how it can have a single molecular weight. Polymers are not my strongest suit, but it might be possible to define an average molecular weight.
  15. I am not aware of any paper that specifically addresses this question. There are experiments one could do. For example, it has been reported in the product literature from BioRad that bovine serum albumin gives about twice the response as egg albumin when both are at the same concentration in mg/mL.