BabcockHall

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On your reactant side there are a total of five carbons, and on your product side, there are four carbons. Also when an amine adds into a ketone or aldehyde, one obtains an imine. There would have to be a reduction to obtain an amine. I have no idea what the ideal solution is, but I might be tempted to look for amino acids or common metabolic intermediates that have the same number of carbon atoms. With respect to the route I suggested or with respect to valine, I would also look into various kinds of known racemase, epimerase, or mutase reactions.

One thing to consider is that transporting CO2 in C-4 plants costs two ATPs IIRC.

Ah, that is more of a physiological question, and I don't know much in that area. With respect to the glucose transporter family, they are not engaged in active transport. On the other hand, glucose transport into the cell from the intestinal lumen is accomplished via active transport.

Nelson and Cox's Principles of Biochemistry.

I mean transporters that reside in the plasma membrane itself. For example there is a family of glucose transporters (GLUTn, where n = 1, 2,...) that facilitate the diffusion of glucose across plasma membranes. Chapter 11 in Nelson and Cox's principles of biochemistry textbook has a good discussion at the advanced undergraduate level.

Amino acids are synthesized from their own pathways, entirely separate from the synthesis of RNA. A family of twenty aminoacyl tRNA synthetase enzymes is responsible for joining the amino acid to its cognate tRNA. These are questions and topics that it takes a biochemistry textbook chapters to develop.

Is this homework? Do you know anything about membrane-bound transporters? These are proteins that have certain specificities for things like glucose and other metabolites.

Would you please say a bit more about good packing and column geometry? With respect to gradients and ion-exchange, I have seen a book the recommended short, broad columns over taller columns. But I don't know whether or not this carries over to affinity columns.

What are your thoughts, so far?

Did you use any other information besides titration to find the identities of the two amino acids? I may be misunderstanding the question, but it might help to think about what glycine could take away.

The manufacturer claims that 5-10 mg of protein binds per mL of resin.

The donation of the nitrogen & hydrogen atoms and the concomitant production of fumarate takes place in two steps overall. One way to think about the second step is that it is simply an elimination reaction. A proton is lost from what was the beta-carbon of aspartate, and -NH3(+) is the leaving group, which departs from the alpha-carbon.

Apologies, I misread your question, and I was pointing the way toward answering a different question. Aspartate is also used as a donor in the biosynthetic pathway that produces inosine monophosphate (check the two steps in the synthesis of AICAR) and in the urea cycle. I disagree that a side chain is necessarily more reactive and can think of some examples to illustrate this. However, I am not sure what makes one nitrogen donor used in one reaction and a different nitrogen donor used in another.

Remember that cells must balance the biosynthesis of AMP and GMP. Does that help?

I would not assume any particular value for Vmax. Instead I would rearrange the Michaelis-Menten equation into the form v/Vmax = (S)/{KM + (S)}. This means that the velocity one calculates will be relative to Vmax. I decided to avoid using concentration brackets in this comment, because I think that they might be causing the unwanted strikethroughs.

I am familiar with some kinds of protein chromatography, but I now have to run a nickel column for the first time. The protein of interest bears a histidine tag, and uur protein is believed to be a dimer or possibly a tetramer of identical subunits. As is typical the nickel column is the first step after sonication of E. coli cells. How do I choose the best volume of gel to use? If I use too little, there will be loss of the protein in the load and wash. If I use too much, the protein is more dilute, and in some sense I am wasting gel. At first glance I can see that one issue is the need to estimate what fraction of soluble cell protein is the protein of interest. I might be tempted to estimate this as being no more than 20% of the soluble protein. A second issue is capacity of the gel, and based on my general knowledge of protein IEX chromatography it occurs to me that there might be some variation from one protein to another, based upon accessibility of the his tag.

I am not sure what you mean by "absorbed topically via the sun."

Is this homework?

The short answer is that oxidation of food creates a proton motive force which is coupled to the synthesis of ATP from ADP and phosphate. It takes several chapters worth of lectures in biochemistry to provide a detailed explanation. I would be hesitant to bring heat directly into this discussion.

I assume that you are referring to Serum glutamic pyruvic transaminase, also known as alanine aminotransferase. We cannot provide medical advice on this forum; that is best done by consulting your physician. You may find this link helpful in terms of background reading. https://www.summitmedicalgroup.com/library/adult_health/tst_sgpt_tst/

Protein is an absolutely essential part of our diet. Without it, we would go into negative nitrogen balance.

Why do you want to know?

A good place to start might be to count carbon atoms and see whether any have been lost or added upon conversion to the products.

Typo. The pyruvate is instead converted into lactate.