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spinqualitylabelsall models PDB ID 3fgc Show:Asymmetric Unit Biological Assembly Drag the structure with the mouse to rotate   Export Animated Image Introduction Luciferases are a class of enzymes that catalyze the oxidation of a long chain aliphatic aldehydes. This reaction results in the formation of a carboxylic acid and the emission of photons in the form of blue-green light.

spinqualitylabelsall models PDB ID 3fgc Show:Asymmetric Unit Biological Assembly Drag the structure with the mouse to rotate   Export Animated Image
3fgc, resolution 2.30Å ()
Ligands:	, ,
Gene:	luxA (Vibrio harveyi), luxB (Vibrio harveyi)
Activity:	Alkanal monooxygenase (FMN-linked), with EC number 1.14.14.3
Related:	1luc, 1brl
Structural annotation: Resources: InterPro : Ipr011251, Ipr016048, Ipr002103, Ipr018235 Pfam : PF00296 UniProt : P07740, P07739
Evolutionary conservation: Toggle Conservation Colors: Rows = identical sequences: Further Information: Caveats, Explanation, Complete Results at ConSurfDB
Resources:	FirstGlance, OCA, RCSB, PDBsum
Coordinates:	save as pdb, mmCIF, xml

Contents 1 Mechanism of Bio luminescence 2 Structural Motifs 3 Applications In Biotechnology 4 Quorum Sensing 5 References

Mechanism of Bio luminescence

Luciferase found in 'Vibrio harveyi' is a heterodimer that is composed of a catalytic α subunit and a homologous but noncatalytic β subunit. The catalytic α subunit houses the FMN cofactor and is connected to the β subunit via a hairpin structure called the "mobile loop." The organic substrate for bacterial luciferase in vivo is myristic aldehyde, although many aliphatic aldehydes of various lengths can induce bioluminescence in vitro.

Structural Motifs

Structure homology-There is a great deal of sequence homology and structural coservation between the α and β subunits. When superimposed over eachother the barrels of the alpha and beta subunits with a deviation of 0.62Å for 42 equivalent α carbons. The region of the beta subunit that contains the 29 residue deletion with respect to the alpha subunit differs notably in arrangement. In the alpha subunit, the α7a helix is straight and extens toward the beta subunit. the region involved with dimerization, helices &#9452 and &#9453 and the hairpin loop structure are exceptionally similar in superposition.

Active Site .

Mobile Loop- Phe2772-thr 288 (β/α)₈ Barrel- The tertiary structure of the α and β subunits is very similar. both subunits fold into a single-domain eight-stranded β/α barrel motif. the two subunits assemble around a parallel four-helix bundle centered on a pseudo 2-fold axis that relates the alpha and beta subunits. .

Subunit Homology-the topology of the αand β subunits is identical. In the alpha subnunit, the γ7-α7 loop is 71 residues long and contains 29 residues not present in the beta subunit.

Applications In Biotechnology

The luciferase assay

Quorum Sensing

Quorum sensing is a population density dependent form gene expression found in many bacteria.

References