A protein was purified to homogeneity. Determination of the mass by gel-filtration chromatography yields 60 kDa....

A protein was purified to homogeneity. Determination of the mass by gel-filtration chromatography yields 60 kDa. Chromatography in the presence of 6 M urea yields a 30-kDa species. When the chromatography is repeated in the presence of 6 M urea and 10 mM β-mercaptoethanol, a single molecular species of 15 kDa results. Which of the following best describes the structure of the protein? A. a dimer of 30 kDa subunits linked by disulfide bonds B. a tetramer of 15 kDa subunits with all subunits linked to each other by disulfide bonds C. a tetramer of 15 kDa subunits with two subunits forming 30 kDa dimers through disulfide bonds D. a tetramer of 30 kDa subunits linked by disulfide bonds E. none of the above

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queen_honey_blossom answered 2 years ago

A protein is purified using ultracentrifugation and found to have a mass of 300 kDa. It...

A protein is purified using ultracentrifugation and found to have a mass of 300 kDa. It is further separated on SDS-PAGE and is found to have a single band corresponding to a mass of 100 kDa. When the protein is treated with beta-mercaptoethanol (breaks disulfide bonds), the SDS-PAGE shows 2 bands, one at 20 kDa and one at 80kDa. Describe the tertiary and quaternary structure, include forces holding the protein together (Hint use prefixes like homo- or dodeca-) So far...

Gel filtration chromatography can also be used to determine the molecular mass of proteins. What additional...

Gel filtration chromatography can also be used to determine the molecular mass of proteins. What additional information might this technique provide as compared to SDS-PAGE or ESI-MS (under standard conditions) Please Explain in depth.

1. Joshua used gel filtration chromatography to purify protein Z from crude homogenate prepared from Arabidopsis...

1. Joshua used gel filtration chromatography to purify protein Z from crude homogenate prepared from Arabidopsis plants. He noticed that protein Z appeared to have eluted from the column in two separate peaks. Using a standard curve, he calculated the MW of protein Z eluted in the first peak to be 156 KDa, and the protein Z eluted in the second peak had the apparent MW of 78 KDa. Which one do you think is the correct MW? What does...

Describe the underlying principle of the gel filtration chromatography method. Why are the larger proteins coming...

Describe the underlying principle of the gel filtration chromatography method. Why are the larger proteins coming out of the column earlier than the small ones? How can gel filtration be used for determining the native size of proteins? Please answer in detail with pictures

In a gel filtration experiment, Be of unknown protein is 22mL while blue dextran is eluted...

In a gel filtration experiment, Be of unknown protein is 22mL while blue dextran is eluted in 8mL. The total volume gel in the column is 15mL. Calculate distribution/partition coefficient of the unknown protein. What is the significance of calculated distribution coefficient?

A certain purified protein has a molecular mass expressed as x kD (1 D = 1/12...

A certain purified protein has a molecular mass expressed as x kD (1 D = 1/12 x mass of 12C atom). Show that an aqueous solution of this protein expressed as x mg/mL is equivalent to a protein concentration of 1mM

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