Question

You ran an SDS-PAGE gel and did every step correctly except you forgot to add SDS! What is the most likely result?

A) Proteins won't separate by size effectively
B) Proteins will separate based on charge
C) Proteins will separate based on shape
D) Proteins won't adhere to the gel

Answer 1

Without SDS in SDS-PAGE, proteins will not separate by size effectively due to the lack of uniform negative charge and denaturation, which is necessary for size-based separation.

Step-by-step explanation:

When performing SDS-PAGE (Sodium Dodecyl Sulfate Polyacrylamide Gel Electrophoresis), SDS serves a crucial role in the process by denaturing proteins and conferring upon them a uniform negative charge. If SDS is not added to the gel, the proteins will not be uniformly negatively charged and will not separate by size effectively. Instead, the proteins might separate based on their native charge and shape, as SDS is essential for breaking the secondary and tertiary structures of proteins and for masking their charges. Since SDS was forgotten in this case, the most likely result is that proteins won't separate by size effectively (Answer A).