Sequence of the lactose permease gene

Area of Science:

• Molecular Biology
• Genetics
• Microbiology

Background:

• The lac operon in Escherichia coli is a fundamental system for studying gene regulation.
• Lactose permease (lacY) is essential for transporting lactose into the bacterial cell.
• Understanding the genetic basis of lactose permease is key to bacterial physiology.

Purpose of the Study:

• To determine the complete nucleotide sequence of the lacY gene in Escherichia coli.
• To identify the intergenic regions surrounding the lacY gene.
• To characterize the predicted protein product of the lacY gene.

Main Methods:

• DNA sequencing of the lacY gene and adjacent regions.
• Bioinformatic analysis to predict protein characteristics.
• Confirmation of the reading frame using mutation analysis.

Main Results:

• The nucleotide sequence of the lacY gene was fully determined.
• Intergenic regions between lacZ, lacY, and lacA were sequenced.
• Lactose permease was predicted to be a 417-residue protein (46,504 MW) with 71% nonpolar residues.
• Reading frame was confirmed via a nonsense mutation analysis.

Conclusions:

• The complete nucleotide sequence of the lacY gene provides a foundational resource for further studies.
• The predicted protein structure offers insights into the function and membrane integration of lactose permease.
• This sequence data is vital for understanding lactose metabolism and transport in Escherichia coli.