c) ogenase reducing acetaldehyde to ethanol, NADH donates a hydride to the carbonyl C, and the oxyanion is transiently stabilized by the Zn2+ divalent cation (see figure on first page), which is then protonated to form the final product. If one assumes that 4-iodopyrazole was bound similarly to the substrate, then which atoms of the inhibitor would be equivalent to the atoms of acetaldehyde? Mark the figure below with the atom of 4-iodopyrazole equivalent to each of the 3 heavy atoms in acetaldehyde. (Use the atom identifiers to identify each one unambiguously: N1, N2, C3, C4, C5, 14.) carbonyl C HC carbonyl O CH3 methyl C

Triosephosphate isomerase (TIM) catalyzes the conversion of dihydroxyacetone phosphate to glyceraldehyde-3-phosphate. The enzyme’s catalytic groups are Glu 165 and His 95. In the first step of the reaction, these catalytic groups function as a general-base and a general-acid catalyst, respectively. Propose a mechanism for the reaction.

Identify the substrate, enzyme, and products in the following chemical reaction: HO но. HO но, HO HO OH HO Lactase NO2 он NO2 OH ONPG p-D-Galactose O-Nitrophenol o-Nitrophenol (ONP) 1. Products B-D-Galactose 2. Substrate Lactase 3. Enzyme ONPG

make a schematic diagram of BChE/AChE inhibitory determination Butyrylthiocholine iodide (BChI), as well as acetylthiocholine iodide(AChI) molecules were utilized as substrate compounds of the reaction. Inthis regard, 5,5′‐dithio‐bis(2‐nitro‐benzoic acid) compound (DTNB) wasused to estimate BChE/AChE activity. In summary, 100 μL Tris buffersolution (HCl, 1.0M, pH 8.0, Tris) and variety of concentrations of thesample solution (50‐200 mL) were added in deionized water and also20 μL of BChE/AChE enzymes solutions added. The mixture was thenincubated for 10 minutes at 20°C. Finally, 50 μL of DTNB (0.5 mM and25 mL) BChI/AChI were added to the incubator mixture. The reactionwas also started by adding 50 μL BChI/AChI. The activity of theseenzymes was evaluated using spectrophotometric spectra with awavelength of 412 nm.

Draw a stepwise mechanism for conversion of radical intermediate A to prostaglandin PGG2.

Write balanced equations for the three known reactions that transfer an amino group to a substrate by condensation with aspartate to give an intermediate that then undergoes a,B-elimination to give the product plus fumarate.

Write a balanced equation for cach of the following reactions or reaction sequences. (a) The reaction catalyzed by PFK-2 (b) The conversion of 2 moles of oxaloacetate to glucose (c) The conversion of glucose to UDP-Gle (d) The conversion of 2 moles of glycerol to glucose (e) The conversion of 2 moles of malate to glucose-6-phosphate

The purinosome contains enzymes that convert the serine hydroxymethyl group to the formyl group of 10-formyltetrahydrofolate. Write a balanced equation for each reaction in this conversion.

Carboxylic acids, such as the one shown below, can be difficult to reduce Provide the name of a reductant A. Explain why this reductant is able to react with the carboxylic acid whereas others cannot (Hint: Draw and discuss the potential reactive intermediates/transition states).

5) A certain aerobic organism is able to metabolize the following glycolipid: "CH,OH OH HO OH A. Draw the 2 resulting structures that would occur upon initial hydrolysis of the O-glycosidic bond. B. Calculate how much ATP is formed upon complete aerobic oxidation of one mole of the compound. Assume that no ATP is produced when one mole of the glycosidic bond in the above compound is hydrolyzed. Show calculation below.