photoproteins are excellent reporter systems because they don’t have virtually background signal. aequorin is the most well-known photoprotein. three improved engineered photoproteins photina, i-photina and c-photina, were also recently developed and optimized for generation of ca2+ mobilization assays precisely. the total light emission is greater than aequorin and their reaction kinetics is a...

A strain of luminous bacteria, Vibrio fischeri Y-1, emits yellow light rather than the blue-green emission typical of other luminous bacteria. The yellow emission has been postulated previously to result from energy transfer from an electronically excited species formed in the bacterial luciferase-catalyzed reaction to a secondary emitter protein, termed the yellow fluorescent protein (YFP). We...

An intermediate identifiable as the emitter in bacterial bioluminescence has been demonstrated. The reaction was carried out at 1 degrees C by mixing purified luciferase-bound FMN 4a-hydroperoxide with long-chain aldehyde (decanal). Simultaneous kinetic measurements of bioluminescence and absorbance showed that the decay of light emission occurred more rapidly than the appearance of the stable ...

Infra-luciferin, an alkene linked analogue of luciferin, gives bioluminescence emission >700 nm and has the potential to be used for multiparametric in vivo imaging. We report here a high yielding, scalable and convergent synthesis of infra-luciferin which will allow the synthesis of other conjugated luciferins for investigation in near-infrared bioluminescence imaging. We demonstrated this pot...

All biological samples emit ultra-low intensity light without any external stimulation. Recently, scientific communities have paid particular attention to this phenomenon, known as ultra-weak photon emission (UPE). UPE has been introduced in the literature as an alternative for biophoton, low-level chemiluminescence and ultra-weak bioluminescence, while it differs from ordinary bioluminescence,...

all biological samples emit ultra-low intensity light without any external stimulation. recently, scientific communities have paid particular attention to this phenomenon, known as ultra-weak photon emission (upe). upe has been introduced in the literature as an alternative for biophoton, low-level chemiluminescence and ultra-weak bioluminescence, while it differs from ordinary bioluminescence,...

Irradiation of bacterial luciferase results in a long lived luminescence which is qualitatively similar to the chemically induced bioluminescence. It has been found that oxygen is required for the emission of photoexcited bioluminescence, but that it need not be present during irradiation. Oxygen must be added promptly, however, for the intermediate has a relatively short lifetime. In the absen...

Bioluminescence represents an operational threat to U.S. Navy nighttime operations because of the vulnerability risk due to detection because of flow-stimulated light emission from naturally occurring plankton. Conversely, bioluminescence presents additional capabilities for detecting moving objects at night, particularly in the littoral zone where conventional acoustic surveillance is severely...

Renilla luciferase (RLuc) is commonly used as a reporter gene either on its own, or in conjunction with firefly and other beetle luciferases. Its use in small animal imaging, however, has been hampered by its 481 nm peaked emission spectrum as blue wavelengths are strongly attenuated in biological tissues. To overcome this difficulty, we focused on red-shifting RLuc through a combination of sem...

Green photosynthetic bacteria exhibit variations in the intensity of their fluorescence during illumination. The initial intensity of fluorescence, measured at the onset of illumination, has a spectrum in which the major pigment Chlorobium chlorophyll predominates. The minor pigment bacteriochlorophyll predominates in the spectrum of the time-varying part of the fluorescence. The spectrum of de...