scholarly journals Diversity and evolution of bacterial bioluminescence genes in the global ocean

2020 ◽  
Vol 2 (2) ◽  
Author(s):  
Thomas Vannier ◽  
Pascal Hingamp ◽  
Floriane Turrel ◽  
Lisa Tanet ◽  
Magali Lescot ◽  
...  

Abstract Although bioluminescent bacteria are the most abundant and widely distributed of all light-emitting organisms, the biological role and evolutionary history of bacterial luminescence are still shrouded in mystery. Bioluminescence has so far been observed in the genomes of three families of Gammaproteobacteria in the form of canonical lux operons that adopt the CDAB(F)E(G) gene order. LuxA and luxB encode the two subunits of bacterial luciferase responsible for light-emission. Our deep exploration of public marine environmental databases considerably expands this view by providing a catalog of new lux homolog sequences, including 401 previously unknown luciferase-related genes. It also reveals a broader diversity of the lux operon organization, which we observed in previously undescribed configurations such as CEDA, CAED and AxxCE. This expanded operon diversity provides clues for deciphering lux operon evolution and propagation within the bacterial domain. Leveraging quantitative tracking of marine bacterial genes afforded by planetary scale metagenomic sampling, our study also reveals that the novel lux genes and operons described herein are more abundant in the global ocean than the canonical CDAB(F)E(G) operon.

2019 ◽  
Author(s):  
Tatiana Mitiouchkina ◽  
Alexander S. Mishin ◽  
Louisa Gonzalez Somermeyer ◽  
Nadezhda M. Markina ◽  
Tatiana V. Chepurnyh ◽  
...  

AbstractIn contrast to fluorescent proteins, light emission from luciferase reporters requires exogenous addition of a luciferin substrate. Bacterial bioluminescence has been the single exception, where an operon of five genes is sufficient to produce light autonomously. Although commonly used in prokaryotic hosts, toxicity of the aldehyde substrate has limited its use in eukaryotes1. Here we demonstrate autonomous luminescence in a multicellular eukaryotic organism by incorporating a recently discovered fungal bioluminescent system2 into tobacco plants. We monitored these light-emitting plants from germination to flowering, observing temporal and spatial patterns of luminescence across time scales from seconds to months. The dynamic patterns of luminescence reflected progression through developmental stages, circadian oscillations, transport, and response to injuries. As with other fluorescent and luminescent reporters, we anticipate that this system will be further engineered for varied purposes, especially where exogenous addition of substrate is undesirable.


2017 ◽  
Vol 71 (0) ◽  
pp. 0-0
Author(s):  
Katarzyna Pajor ◽  
Daniel Sypniewski ◽  
Ilona Bednarek

Bioluminescence has been studied for many years by scientists. There are numerous mechanisms of that phenomenon; among them bacterial bioluminescence is the most frequently found in nature. This type of bioluminescence is determined by the appearance of lux operon, which encodes all elements necessary to produce light emission and it does not require any additional substrates supply. Another commonly found example of bioluminescence mechanism is performed by Photinus pyralis. Luciferase of P. pyralis named FLuc requires D-luciferin as a substrate. Bioluminescence is also characteristic for many deep-sea organisms. Most of them are based on oxidation reaction of coelenterazine to coelenteramide mediated by RLuc or GLuc luciferases. Due to the variety of bioluminescence mechanisms in nature, it has become possible to apply them in many sensitive methods that can be used in molecular biology and medicine. The most significant application of bioluminescence is BLI (bioluminescence imaging). This method is cheap and nontoxic which allows both in vitro and in vivo imaging. BLI applications include, e.g. protein-protein interactions, stem cells labeling, tracking of viral, bacterial, fungal and parasitical infections, and carcinogenesis analyses. Bioluminescence has also been used in the creation of modified cell systems capable of light emission in response to certain analytes and thus very sensitive biosensors have been generated. Other important areas of bioluminescence application are immunoassays, ATP assays, and BART analysis (bioluminescent assay in Real-Time) – a very sensitive technique which allows scientists to estimate nucleic acids amplification.


2021 ◽  
Author(s):  
Carola Gregor

AbstractThe bacterial bioluminescence system enables light production in living cells without an external luciferin. Due to its relatively low levels of light emission, many applications of bioluminescence imaging would benefit from an increase in brightness of this system. In this report a new approach of mutagenesis and screening of the involved proteins is described that is based on the identification of mutants with improved properties under rate-limiting reaction conditions. Multiple rounds of screening in Escherichia coli resulted in the operon ilux2 that contains 26 new mutations in the fatty acid reductase complex which provides the aldehyde substrate for the bioluminescence reaction. Chromosomal integration of ilux2 yielded an autonomously bioluminescent E. coli strain with 7-fold increased brightness compared to the previously described ilux operon. The ilux2 strain produces sufficient signal for the robust detection of individual cells and enables highly sensitive long-term imaging of bacterial propagation without a selection marker.


Derrida Today ◽  
2020 ◽  
Vol 13 (1) ◽  
pp. 72-94
Author(s):  
Bernard Stiegler

These lectures outline the project of a general organology, which is to say an account of life when it is no longer just biological but technical, or when it involves not just organic matter but organized inorganic matter. This organology is also shown to require a modified Simondonian account of the shift from vital individuation to a three-stranded process of psychic, collective and technical individuation. Furthermore, such an approach involves extending the Derridean reading of Socrates's discussion of writing as a pharmakon, so that it becomes a more general account of the pharmacological character of retention and protention. By going back to Leroi-Gourhan, we can recognize that this also means pursuing the history of retentional modifications unfolding in the course of the history of what, with Lotka, can also be called exosomatization. It is thus a question of how exteriorization can, today, in an epoch when it becomes digital, and in an epoch that produces vast amounts of entropy at the thermodynamic, biological and noetic levels, still possibly produce new forms of interiorization, that is, new forms of thought, care and desire, amounting to so many chances to struggle against the planetary-scale pharmacological crisis with which we are currently afflicted.


Materials ◽  
2021 ◽  
Vol 14 (9) ◽  
pp. 2303
Author(s):  
Silvana De Iuliis ◽  
Roberto Dondè ◽  
Igor Altman

The application of pyrometry to retrieve particle temperature in particulate-generating flames strictly requires the knowledge of the spectral behavior of emissivity of light-emitting particles. Normally, this spectral behavior is considered time-independent. The current paper challenges this assumption and explains why the emissivity of oxide nanoparticles formed in flame can change with time. The suggested phenomenon is related to transitions of electrons between the valence and conduction energy bands in oxides that are wide-gap dielectrics. The emissivity change is particularly crucial for the interpretation of fast processes occurring during laser-induced experiments. In the present work, we compare the response of titania particles produced by a flame spray to the laser irradiation at two different excitation wavelengths. The difference in the temporal behavior of the corresponding light emission intensities is attributed to the different mechanisms of electron excitation during the laser pulse. Interband transitions that are possible only in the case of the laser photon energy exceeding the titania energy gap led to the increase of the electron density in the conduction band. Relaxation of those electrons back to the valence band is the origin of the observed emissivity drop after the UV laser irradiation.


Nanophotonics ◽  
2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Shaoni Kar ◽  
Nur Fadilah Jamaludin ◽  
Natalia Yantara ◽  
Subodh G. Mhaisalkar ◽  
Wei Lin Leong

Abstract Perovskite semiconductors have experienced meteoric rise in a variety of optoelectronic applications. With a strong foothold on photovoltaics, much focus now lies on their light emission applications. Rapid progress in materials engineering have led to the demonstration of external quantum efficiencies that surpass the previously established theoretical limits. However, there remains much scope to further optimize the light propagation inside the device stack through careful tailoring of the optical processes that take place at the bulk and interface levels. Photon recycling in the emitter material followed by efficient outcoupling can result in boosting external efficiencies up to 100%. In addition, the poor ambient and operational stability of these materials and devices restrict further commercialization efforts. With best operational lifetimes of only a few hours reported, there is a long way to go before perovskite LEDs can be perceived as reliable alternatives to more established technologies like organic or quantum dot-based LED devices. This review article starts with the discussions of the mechanism of luminescence in these perovskite materials and factors impacting it. It then looks at the possible routes to achieve efficient outcoupling through nanostructuring of the emitter and the substrate. Next, we analyse the instability issues of perovskite-based LEDs from a photophysical standpoint, taking into consideration the underlying phenomena pertaining to defects, and summarize recent advances in mitigating the same. Finally, we provide an outlook on the possible routes forward for the field and propose new avenues to maximally exploit the excellent light-emitting capabilities of this family of semiconductors.


2021 ◽  
Vol 9 (9) ◽  
pp. 3052-3057
Author(s):  
Jerzy J. Langer ◽  
Ewelina Frąckowiak

H+LEDs are light emitting devices based on a protonic p–n junction; now with no organic polymers. The unique are non-linear optical effects: collimated light beams and stimulated Raman scattering (SRS), observed while generating intense light pulses.


RSC Advances ◽  
2015 ◽  
Vol 5 (35) ◽  
pp. 27491-27495 ◽  
Author(s):  
Wei Tang ◽  
Ye Sun ◽  
Miao Yu ◽  
Xiao Liu ◽  
Yongqi Yin ◽  
...  

White-light emission from SrTiO3:Pr3+ nanoparticles has been achieved by tuning combination of the 3P0 and 1D2-related blue to red emissions.


2013 ◽  
Vol 211 (3) ◽  
pp. 651-655 ◽  
Author(s):  
Jorge Oliva ◽  
Elder De la Rosa ◽  
Luis Diaz-Torres ◽  
Anvar Zakhidov

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