Question

A protein sample complex consists of two proteins, a smaller protein, X, and a larger protein, Y. Protein X is composed of two polypeptide chains linked by disulfide bonds. Protein Y is composed of three polypeptide chains linked by disulfide bonds. The complex is analyzed by native PAGE, reducing SDS‑PAGE and non‑reducing SDS‑PAGE. Native PAGE does not include sodium dodecyl sulfate, or SDS. Reducing SDS‑PAGE uses both SDS and a reducing agent in the buffer. Non‑reducing SDS‑PAGE uses SDS, but no reducing agent. Match each gel pattern to an experimental method. The first lane in each gel is a molecular weight ladder.

Answer 1

The correct match to the different gels are presented below.

Step-by-step explanation:

The SDS method can separate different proteins by their size and also provides approximate molecular weight and subunit composition. The native PAGE is the gel where you find only one 250 kDa band because the conditions that the complex of proteins is treated can't break nor reduce the complex. The gel with two bands represents the non-reducing SDS-PAGE and the gel with 3 bands represents the reducing SDS-PAGE, because the reducing conditions can from the SDS-PAGE are responsible to break the complex and also the disulfide bonds.