Monthly Archives: September 2012

Luciferase

Firefly luciferase

Firefly Luciferase is one of several fluorescent proteins. Other common ones are Green Fluorescent Protein, Renilla Luciferase, and Bacterial Luciferase.

Firefly luciferase catalyzes the oxidation of luciferin, the substrate in fireflies that makes them light up. The oxidation of luciferin, which is when oxygen is fused with the luciferin, happens in two steps. First the luciferin bonds with Mg2and ATP to create luciferyl adenylate and PPi (Pyrophosphate). Then the luciferyl adenylate reacts with diatomic oxygen to create oxyluciferin, AMP, and light.

Luciferase is interesting because of its compact two-part domain structure. The active site of luciferase is thought to be located in the cleft between the C and N-terminuses (Fig. 5). The C-terminus is the smaller part of luciferase, and it has the free carboxyl group. The larger N-terminus has the free amine group. During the reaction, luciferase undergoes a reversible conformational change, where the cleft between the C and N-terminus close up. This prevents water from entering the reaction and hydrolyzing one of the reactants.[1]

Protein Structure of Firefly Luciferase

Protein Structure of Firefly Luciferase

 

In the theorized interaction that I modeled, the two very separate domains of luciferase are very important to the interaction. Because they split easily into the two separate terminuses, it allows my idea for a split catalyst genetic-specific biocatalyst. The recombination of the two domains is central to the idea and dependent on the two very separate domains.


[1] Conti, Elena, Peter Brick, and Nick P Franks. “Crystal structure of firefly luciferase throws light on a superfamily of adenylate-forming enzymes.” Structure 4.3 (1996): 287-298. Print.

Hello world!

To do a quick review if you haven’t read the about me section, (or hopefully that’s where the thing I just published went), I’m a Seattle student trying to get data to back up my idea of a genetic specific catalyst. I won 1st place in the highly competitive molecular modeling category at the NWABR biotech expo in March 2012, and have modified my project and now hope to enter it in the INTEL fair or something of the like.

A genetic specific catalyst would be highly useful in the field of medicine. In the first stages of my project, I’m plannign on using a split fluorescent protein to show proof of interaction. In this way, I could send my system in vitro into blood samples as a diagnostic tool, testing for a specific genetic sequence in the sample. For example, a genetic mutation in a virus that makes it antibiotic resistant. Or to test for a genetic disorder in young children.

Right now I’m in the process of finalizing a search for lab space to run my project in, and some form of mentorship to help me with more complicated procedures. I hope to originally run my project with a fluorophore and quencher model to show specificity, and to move along to protein bonding with time. Hopefully I’ll be able to get in the lab soon, and will be able to post some procedures and or/ results.

(If you’re confused and don’t understand what this weird genetic specific catalyst thing is, check out my About page to learn more)

Thank You so much,

Katriona