Answer the following questions. a Acid phosphatase catalyzes hydrolysis of 4.5 m

Question

Answer the following questions. a Acid phosphatase catalyzes hydrolysis of 4.5 mu mol of pNPP in 5 minutes when 225 mu g of acid phosphatase is present in 5 mL. calculate the i) rate of reaction, ii) enzyme activity and iii) specific activity. b) Estimate k the first order rate constant for lysozyme when V_max = 7.5 mu mole/L/min and K_m = is 2.5 c) Determine the K_m using the data shown in the plot below: c) Determine the k_m using the data shown in the plot below: a) 0.1 mM b) 02 mM c) 2.0 mM d) 40 mM e) K_m cannot be determined from this data

Explanation / Answer

(8)

(a)

(i)

Reaction rate = Amount of substrate hydrolyzed ( in terms of conc.) / Time = (4.5/0.005)/5 = 180 uM/min

(ii)

Enzyme activity = Rate * Volume = 180*0.005 = 0.9 umol/min

(iii)

Specific activity = Enzyme activity/enzyme mass = 0.9/2.25 = 0.4 mol/(g.min)

(c)

Here the correct answer is that the value cannot be determined from the fraph given, because it is not sure whether the reaction rate increases beyond the value shown in the graph. Assuming that the rate achieved is actually the maximum reaction rate Vm (and equals 4 in this case), the Km is the substrate conc. corresponding to Vm/2.

From the graph we can approximate it as 0.2 mM, because at [S] = 0.2 mM, V = 2 = Vm/2

Related Questions

Navigate

• Browse (All)
• Browse A
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.