BamHI

BamHI is a restriction enzyme derived from the bacterium Bacillus amyloliquefaciens strain H. It is one of the many tools used in molecular biology for DNA manipulation and analysis. BamHI recognizes the palindromic DNA sequence 5'-GGATCC-3' and cleaves it in a staggered manner, leaving behind a 4-nucleotide long, 5' overhanging end. This specific cut facilitates the creation of recombinant DNA molecules, making BamHI invaluable in genetic engineering, cloning, and molecular cloning practices.

Function and Application

BamHI's primary function is to cleave DNA at specific sites, allowing scientists to insert or remove genetic material with precision. This capability is fundamental in constructing recombinant DNA molecules, which are essential for various applications, including gene therapy, the production of genetically modified organisms (GMOs), and the development of vaccines. Additionally, BamHI is frequently used in molecular cloning techniques to clone DNA fragments into plasmids or other vectors for further analysis or manipulation.

Structure

The enzyme BamHI is a type II restriction endonuclease, characterized by its ability to cut DNA at specific recognition sites away from its own bacterial DNA, thus protecting the host genome from cleavage. The structure of BamHI, as determined through X-ray crystallography, reveals that it operates as a homodimer, meaning two identical subunits come together to form the active enzyme. This dimerization is crucial for its function, as it allows the enzyme to bind to DNA and catalyze the cleavage reaction efficiently.

Usage in Molecular Biology

In the laboratory, BamHI is used in a variety of molecular biology protocols. Its ability to create sticky ends makes it particularly useful in DNA ligation processes, where DNA fragments are joined together. Scientists often use BamHI in combination with other restriction enzymes to generate complex DNA constructs. For example, in cloning experiments, BamHI can be used to open a plasmid vector and insert a DNA fragment of interest that has been cut with the same enzyme, ensuring that the ends are compatible for ligation.

Safety and Handling

Like other restriction enzymes, BamHI must be handled with care in the laboratory. It requires specific storage conditions, typically at -20°C, and buffer conditions to maintain its activity. Additionally, safety protocols must be followed to prevent contamination and ensure the integrity of the DNA samples being manipulated.

See Also

• Molecular cloning
• Genetic engineering
• Recombinant DNA
• DNA ligation
• Plasmid
• X-ray crystallography

External Links

• National Center for Biotechnology Information (NCBI)
• Addgene's Guide to Restriction Enzyme Digest