If a slight deficiency in the Vitamin B1 derivative Thiamine Pyrophosphate (TPP) leads to an accumulation of substrates for reactions utilizing this cofactor, A) what substrates would ‘accumulate’ in a human after eating a an enormous amount of sugar-laden Halloween candy, AND what would be the regulatory consequences on carbohydrate metabolism? B) What substrates would accumulate in yeast cells cultured under anaerobic (no oxygen) conditions AND what would be the regulatory consequences on carbohydrate metabolism? C) What substrates would accumulate in plant cells incorporating carbon and generating energy solely using photosynthesis?

An enzyme with an unknown reaction mechanism has been isolated and is being investigated in the lab. Based on the information given below, propose one or more specific catalytic strategies (covalent, acid-base, and/or metal ion catalysis) used by the enzyme and predict the role of each catalytic residue in the enzyme's reaction cycle. Explain your reasoning. (a) Mapping of the active site with substrate analog showed that it contains a critical Ser residue. (b) Studies conducted in buffers of varying pH showed that the enzyme is sensitive to pH changes and has two catalytically important residues with pKa values of ~10.5 and ~4.0. (c) Substitution of the Ser residue with Ala resulted in a five-fold increase in the KM but had no effect on the kcat. (d) The reaction rate was insensitive to the addition of metal chelators such as EDTA and EGTA.

5

The enzyme pyruvate carboxylase is discovered in a bacterium that was thought not to contain it; in this case study, you’ll see how researchers study and characterize the enzyme, and, ultimately, show how it fits into a metabolic pathway. Following purification of the PYC enzyme by avidin-Sepharose affinity chromatography, the investigators carried out several experiments to characterize the enzyme. First, they ran samples of the enzyme on denaturing and non-denaturing gels; the results are shown in the figure to the right. In addition, they ran the protein through a calibrated gel filtration column, the results of which indicated that the PYC enzyme had a molecular weight of 540 kiloDaltons. In the figure, the rightmost column are where molecular weight standards of various sizes would occur if they’d been on the gels. Part A: There are four identical subunits in the PYC enzyme. And there are not four domains in the denaturing gel. Based on the image provided attached, how many chains…

Describe how a) Mean Arterial Pressure, b) Maximal Oxygen Consumption, and c) Blood Flow are determined using its formula. In addition, you should explain what those factors are including cardiac output, stroke volume, heart rate, resistance, a-vO2 difference, etc. Describe how many ATPs can be generated by complete cycles of beta oxidation of free fatty acid with 20 carbons. You should indicate how many cycles of beta oxidation and Krebs cycle, and total number of products as well

there are A-D questions to this picture set up. A) What enzyme catalyzes this reaction? B) What is Delta G, please answer in Joules, K=19 C) If concentration of Glucose-1_Phosphate is 48.82 uM at equalibrium, what is the concentration of Glucose-6-phosphate in uM? D) If the reaction is NOT at equalibrium, what is delta G at 25C if the concentration of Glucose-1-phosphate is 15.04 uM and concentration of Glucose -6-phosphate is 1.62 mM? please answer in Joules and in significant figures. *note, 10^3uM in 1 mM   Thank you!!

The amount of glucose 6-phophate that is used by the glycolytic or pentose phosphate (b) pathways is determined by the current metabolic state of the cytosol. This regulation is achieved in part via allosteric regulation of the first committed step of the pentose phosphate pathway. (i) What metabolite is the key allosteric regulator of the pentose phosphate pathway, and what enzyme does this metabolite regulate? (ii) What happens to glucose 6-phopshate in the limiting case when this metabolite is in excess? (iii) What happens to glucose 6-phophate in the limiting case when this metabolite is absent?

Q) You are following the metabolism of aspartate that is equally labeled on all 4 carbons. Following a transamination aspartate is converted into oxaloacetate. Assuming the resulting Oxaloacetate is used as the substrate for the TCA cycle answer the following questions: a) Describe ALL the oxaloacetate molecules that would result from the first turn of the TCA cycle. b) Briefly describe how there is still label detected on the carboxylic acids even though they were removed as CO2 during the first turn of the cycle. (2 sentences MAX)

The following nutrient molecule is digested and transported to a cell where it undergoes further catabolism: но c-(CH;)14-CH3 di In the table below, list the important products of the complete B oxidation of this molecule. • In the first column of the table, write the chemical formula, name, or standard biochemical symbol for a product molecule. In the second column, write the total number of these molecules produced. • Only list the Important products, including (1) molecules with any of the carbon atoms that were in the original molecule, (2) energy storage molecules (like ATP), and (3) newly oxidized or reduced coenzymes. List each product molecule on a separate row. You can add more rows if you need them. • Be sure you write the number of product molecules formed by the complete B oxidation of the molecule above. • Do not include the products of any catabolic activity that happens before or after B oxidation, including any necessary activation. If the molecule contains small parts…

1. In a catabolic pathway, metabolite X gets converted into metabolite Y, metabolite X 0 J mol-¹ and AG' is <0 J mol-¹ for this reaction. a) At standard states, is this reaction favorable? b) Is the reaction favorable or unfavorable at cellular condition? c) Is this an endergonic or exergonic reaction in the cell? d) Would you describe this as a thermodynamically downhill or uphill reaction in the cell?