Án enzyme that follows Michaelis-Menten kinetics has a KM value of 3.00 µM and a kat value of 181s1. At an initial enzyme concentration of 0.0100 uM, the initial reaction velocity was found to be 1.07 x 10- µM/s. What was the initial concentration of the substrate, [S), used in the reaction ?

An enzyme uses a lysine and a histidine as general acid-base catalytic residues. In one direction of the reaction, the lysine and histidine residues are typically protonated (~NH3*, ~Im), but in the other direction of the reaction, the two residues are "reverse protonated" (~NH2, ~Hlm*) (see below scheme). A pH profile of the reaction at various pH values yielded estimates of 7.57 and 9.30 for the macroscopic ionization constants pk,' and pK2, respectively. A separate set of experiments with site-speciffic variants of the enzyme yielded an estimate of 8.78 for the microscopic ionization constant pKp. Given this information, what is the value of the microscopic ionization constant pKA? Report your answer to the nearest hundredth. Lys-NH3* His-HIm" KB H KA H* Lys-NH2 Lys-NH3* His-HIm" His-Im Kc H* Kp Lys-NH2 His-Im

Describe reaction between AP and PNPP and how is used to determine the kinetic parameters of AP. i. İndicate the value for the activity of AP(which is 3.08) What does it mean? Is your enzyme active or not? What does it say about the purity of your enzyme? ii. How the purification process affects the activity?

A set of biomolecules listed in the table at right are in solution at pH 6.8, when they are passed through the multi-step separation process shown below. The sample passes through an ultrafilter with MWCO of 50,000 (assume this filter gives a perfect separation of molecules above and below the MWCO), and the retentate then flows through an ion exchange column filled with beads that have a positive charge under the operating conditions (pks = 7.3). Inlet Biomolecule Mixture pH 6.8 Ultrafiltration MWCO 50,000 Permeate Retentate lon Exchange Column Biomolecule Molecular weight pl A 68,000 4.2 B 92,600 9.6 C 144,000 A-3. Which biomolecules (A, B, C, etc.) exit the process in the permeate stream? K C-3. Which biomolecules are retained inside the ion exchange column? D E F G H B-3. Which biomolecules exit the process after passing through the ion exchange column? 5,800 68,000 Packed with DEAE cellulose beads, which have positively charged groups below a pH of 7.3 156,000 45,000 16,000 None…

You are working at a major pharmaceutical company, and you have purified an engineered enzyme, and you need to determine the protein stability (kJ/mol). Accordingly, you have collected equilibrium unfolding data using the chemical denaturant urea at 20°C, pH 7.5 and I atmosphere using fluorescence spectroscopy. a) Determine the protein stability (AG [kJ/mol]) via nonlinear least squares (using the available data). b) Write the partial differential equation (i.e., general functional form, variable, constants). c) Describe what would happen to the isotherm if the temperature was increased to 25 °C. Urea [M] 0 0.25 0.5 0.75 1 1.25 1.5 2 2.25 2.5 2.75 3 3.25 3.5 3.75 4 4.25 4.5 4.75 5 FL 340nm 316 315.5 315 314.5 314 315 300 275 225 125 75 60 55 54 53 52.5 52.25 52 51.75 51.5 dG = Vdp-SdT+μA dnд + μB dng dGp = μA dnA+ μg dng A = Folded State B = Unfolded State

make a Gibbs free energy graph as free energy as y-axis a for the transition state as a function of [Gdn HCl] (x-axis) with a line of best fit

An enzyme contains an active site aspartic acid with a pKa = 5.0, whichacts as a general acid catalyst. On the accompanying template, draw thecurve of enzyme activity (reaction rate) versus pH for the enzyme (assumethat the protein is stably folded between pH 2–12 and that the active siteAsp is the only ionizable residue involved in catalysis). Briefly explain theshape of your curve.

Can you please help show how to find Kr?

You are evaluating the kinetics of an enzyme catalyzed reaction containing 5.5 μM total enzyme and 11.2 μM substrate. At this substrate concentration, you determine that the Vo = 88.6 μmol mL-¹. s-¹. If the Vmax 833.3 mM s the KM is: . == " 30.9 μΜ 10.4 μΜ Ο 124.6 μΜ 234 μΜ 94.5 μM

A purified protein fraction has a total sample volume of 360 µL.  The sample has a corrected A280 of 0.484, and the blank corrected A280 was 0.052.  (Both values were measured with a path length of 1.00 cm.)  If 5.00 µL of the sample was used in a reaction, calculate the mass of protein in the reaction (in µg).