Green fluorescing protein (GFP) is a naturally occurring fluorescent protein that emits a green light when exposed to specific wavelengths of light. It is derived from an organism called Aequorea victoria, a species of jellyfish found in the Pacific Northwest. GFP has become an invaluable tool in various fields of research, including molecular biology, genetics, and cell biology.
GFP is characterized by its ability to fluoresce without requiring any additional co-factors or enzymatic activity. It consists of 238 amino acids and forms a unique chromophore within its core, which is responsible for its fluorescent properties. The protein structure of GFP includes an 11-stranded beta-barrel surrounded by alpha helices.
The fluorescence of GFP arises from a chemical reaction called "excitation and de-excitation." When exposed to ultraviolet or blue light, the GFP absorbs photons and transitions from its ground state to a higher energy state, called the excited state. This absorbed energy is then released in the form of green light when the excited GFP molecule returns to its ground state. The specific wavelength of light required to excite GFP is approximately 395-470 nm.
GFP has had a transformative impact on the study of biological phenomena. Researchers have harnessed its fluorescence by genetically engineering organisms to express GFP, allowing them to visualize and track specific molecules and cellular structures in real time. This has provided unprecedented insights into cellular processes, such as protein localization, gene expression, and cell division, among many others.
In summary, green fluorescing protein (GFP) is a naturally occurring protein derived from Aequorea victoria that emits green light when exposed to specific wavelengths. Its unique properties make it an essential tool in various scientific disciplines, enabling researchers to investigate a wide range of biological processes.
