Question

27. Fill the table below

    Milk                   Interpolated                           Dilution Calculated     

  Dilutions                                       [ ] Factor                             Concentration

1/10 SM	0.86 g/ µL
1/50 SM	0.35   g/ µL

28. You wish to carry out a 1/5 dilution of a (full strength) milk sample in a final volume of 12 mL. How much of your full-strength milk solution will you need? Show your work and circle your answer.

30. When an enzyme is converting substrate into a product as fast as possible, the enzyme is referred to as working at its __________________________. Since this can only be reached when there is an excess of substrate…. Term for this condition of an overabundance is: _____________________________.

Table containing the data form SDS- PAGE gel:

       Sample _                       Rm:

       Protein A                   0.77

Protein B                   0.56

Protein C                   0.45

Protein D                   0.24

Protein E                   0.33

. Which of the Proteins has the largest molecular weight? __________________________.

. Which of the proteins has the smallest molecular weight? __________________________.

You have been given a protein sample with an initial concentration of 125 micrograms/microliter. You will analyze this solution using SDS-PAGE, loading the gel with 20 micro grams and 30 micrograms of protein from your sample.

A) In the space below, clearly outline the dilutions(s) that you will perform (applying the dilution we discussed in lab).

B) What volume will you need to load for the 20 µg and 30 µg samples? Keep in mind, your concentration volume to load in the gel must be between 5 µL and 25 µL. Show your work.

Answer 1

question 27-

For the 1/10 SM, we have 0.86 g/uL interpolated factor. This suggests after diluting the sample we have 0.86 g/uL milk solids concentration. Now calculate the dilution as below-

For 1/10 dilution the dilution factor is 10^-1 or 0.1; this is just the inversed value.

The concentration is = Interpolated factor x 1/Dilution factor

= 0.86 g/uL x 10

= 8.6 g/uL

For the 1/50 SM:

The dilution factor = 0.02

The concentration is = Interpolated factor x 1/Dilution factor

= 0.35 g/uL x 50

=17.5 g/uL

However, the concentration should be in ug/uL.