You Are Trying to Determine the Sequence of a Protein

question 85

Essay

You are trying to determine the sequence of a protein that you know is pure. Give the most likely explanation for each of the following experimental observations. You may use a simple diagram for your answer.
(a) The Sanger reagent (FDNB, fluorodinitrobenzene) identifies Ala and Leu as amino-terminal residues, in roughly equal amounts.
(b) Your protein has an apparent M_r of 80,000, as determined by SDS-polyacrylamide gel electrophoresis. After treatment of the protein with performic acid, the same technique reveals two proteins of M_r 35,000 and 45,000.
(c) Size-exclusion chromatography (gel filtration) experiments indicate the native protein has an apparent M_r of 160,000.

---

Definitions:

Time Premium

The portion of an option's price that exceeds its intrinsic value, representing the value placed on the remaining time until expiration.

Preferred Shareholders

Preferred shareholders are investors who own shares of a company's stock with preferential rights over common stock, particularly in dividend payments and upon liquidation.

Common Shareholders

Individuals or entities that own shares in a corporation, giving them rights to dividends and a say in company matters through voting.

Bondholders

Individuals or institutions that hold the debt securities issued by corporations or governments, thus lending them money in exchange for periodic interest payments and the return of principal at maturity.