Question

A procedure in which the gene for an integral membrane protein is altered in such a way that the spatial relationships between some of the amino acids in the protein can be revealed is called ________?

1) site-directed mutagenesis
2) site-directed amenuensis
3) hydropathy plots
4) electron paramagnetic resonance (EPR) spectroscopy
5) infrared spectroscopy

Answer 1

Site-directed mutagenesis is the procedure used to alter genes of integral membrane proteins to study their structure, by means of specific DNA mutation techniques such as primer design and PCR.

Step-by-step explanation:

The technique used to alter the gene for an integral membrane protein in order to reveal the spatial relationships between some of the amino acids in the protein is called site-directed mutagenesis. This method enables precise modifications at specified sites within a gene. The process typically involves:

1. Designing primers and conducting PCR to introduce specific mutations.
2. Synthesizing plasmid DNA containing the mutated sensor RNA sequence (plasmid prep).
3. Enzymatic cutting of this plasmid DNA (restriction digest).
4. Synthesizing the sensor in vitro (RNA transcription).
5. Purificating of the mutant sensor RNA.

These steps are crucial for understanding how membrane proteins, like those with hydrophobic alpha-helical domains, interact within the cell membrane and function, such as forming dimers or creating pores for ion transport.