Shining Light on the Secreted Luciferases of Marine Copepods: Current Knowledge and Applications

Abstract

Copepod luciferases—a family of small secretory proteins of 18.4–24.3 kDa, including a signal peptide—are responsible for bright secreted bioluminescence of some marine copepods. The copepod luciferases use coelenterazine as a substrate to produce blue light in a simple oxidation reaction without any additional cofactors. They do not share sequence or structural similarity with other identified bioluminescent proteins including coelenterazine‐dependent Renilla and Oplophorus luciferases. The small size, strong luminescence activity and high stability, including thermostability, make secreted copepod luciferases very attractive candidates as reporter proteins which are particularly useful for nondisruptive reporter assays and for high‐throughput format. The most known and extensively investigated representatives of this family are the first cloned GpLuc and MLuc luciferases from copepods Gaussia princeps and Metridia longa, respectively. Immediately after cloning, these homologous luciferases were successfully applied as bioluminescent reporters in vivo and in vitro, and since then, the scope of their applications continues to grow. This review is an attempt to systemize and critically evaluate the data scattered through numerous articles regarding the main structural features of copepod luciferases, their luminescent and physicochemical properties. We also review the main trends of their application as bioluminescent reporters in cell and molecular biology.

Coelenterazine-Dependent Luciferases as a Powerful Analytical Tool for Research and Biomedical Applications

“…The luciferases of marine copepods Metridia and Gaussia , although their properties are still poorly studied, are attracting attention as promising reporters because of their small size, unique thermal stability, and genetically encoded secretion system. This makes them ideal reporters for in vivo applications by providing capability of monitoring cellular events via measuring bioluminescence in culture media without cell lysis (see recent comprehensive review, [ 174 ]).…”

Photorhabdus LuminescensToxin complex (TCC) a recombinant injection nano-machine – delivery of recombinantYersinia enterocoliticaYopT

“…M-Luc7 (cloned without the signal peptide) has a small molecular weight (152 aa, 16.5 kDa) and a basic character (pI = 8.66). It shares no sequence or structural homology to Renilla or Firefly luciferases (for review see (Markova, Larionova et al, 2019)) although, like Renilla luciferase, it uses commercially available cell penetrating coelenterazine as substrate for producing blue light.…”

Flash properties of Gaussia Luciferase are the result of covalent inhibition after a limited number of cycles

“…The enzyme-catalyzed reaction requires oxygen, but no other cofactors. Apart from CO2 and light the main CTZ-derived product has not been experimentally determined, but is presumed to be coelenteramide, as in other CTZ utilizing luciferases (Markova et al, 2019). In keeping with its extracellular location, GLuc contains 5 disulfide bridges (Rathnayaka et al, 2011).…”

“…GLuc has been developed as a tool in several applications ranging from reporter of gene expression, in bacteria and mammals to split-protein-complementation assays (Maguire et al, 2009;Kim et al, 2011;Remy et Michnick, 2006;Markova et al, 2019). In particular, it has been promoted as a sensitive and useful tool for studying gene expression, systems of secretion (Tannous, 2009) or for monitoring disulfide bond formation (Yu et al, 2018).…”