Genetically encoded oxygen sensor tracks changes in oxygen levels with very high sensitivity

A fluorescent protein sensor able to provide real-time information on dynamic changes in oxygen levels with very high sensitivity.

Figure 1. Monitoring of photosynthetic oxygen production in cyanobacteria using ANA sensor ANA sensor was added to the culture of cyanobacteria, and the fluorescence of ANA sensor was monitored. Fluorescence of ANA sensor started to increase after 15 min of illumination, indicating the ANA sensor detected oxygen produced by cyanobacteria.
Figure 1. Monitoring of photosynthetic oxygen production in cyanobacteria using ANA sensor ANA sensor was added to the culture of cyanobacteria, and the fluorescence of ANA sensor was monitored. Fluorescence of ANA sensor started to increase after 15 min of illumination, indicating the ANA sensor detected oxygen produced by cyanobacteria.

In light of a protein from E. coli, researchers at Tokyo Tech have built up a fluorescent protein sensor ready to give ongoing data on unique changes in oxygen levels with high sensitivity. As the oxygen level is a noteworthy determinant of cell work, the thought behind this sensor may reform our capacity to recognize cell changes of basic significance, for example, in tumors and following stroke and heart attack.

Oxygen is a noteworthy player in the biochemical procedures that make life on earth possible. Having the capacity to quickly and precisely measure oxygen levels inside living cells could be helpful in a few regions of biology, including physiology, medicine, and bioengineering. For instance, oxygen levels in disease cells can influence their reaction to anti-cancer treatments, while oxygen levels in tissues following a stroke or heart assault can impact treatment and recovery.

Prof. Hisabori said, “This new type of oxygen sensor that may dramatically alter our ability to detect changes in cellular oxygen levels. Limitations in previously developed methods to measure oxygen levels make it difficult to analyze oxygen levels in living cells” notes Prof. Hisabori, “so we aimed to overcome these limitations by developing a genetically encoded sensor that can provide real-time information on the dynamic changes of oxygen levels in living cells.”

The analysts utilized a protein called the direct oxygen sensor protein, or DosP, from the bacterium E. coli, which can either tie or discharge oxygen depending upon the oxygen levels inside the cell. The piece of the protein that can tie oxygen was detached and connected to a fluorescent protein, before assessing the fluorescence intensity of the subsequent item under various oxygen levels.

Scientists found that the fluorescence of their novel protein, named ANA sensor (anaerobic/vigorous sensing fluorescence protein), expanded within the sight of oxygen and diminished without oxygen, subsequently effectively following the dynamic changes in oxygen content. Further improvement enabled them to tweak the protein too.

By utilizing the ANA sensor, photosynthetic oxygen generation by a photosynthetic microorganism (cyanobacteria) could be observed. Quite, in a sensational change over past oxygen recognition techniques, changes in oxygen levels are reflected by changes in ANA sensor fluorescence with high affectability empower more exact measurement of oxygen levels.

By using the ANA sensor, photosynthetic oxygen production by a photosynthetic microorganism (cyanobacteria) could be monitored. Notably, in a dramatic improvement over previous oxygen detection methods, changes in oxygen levels are reflected by changes in ANA sensor fluorescence with very high sensitivity.

Dr. Nomata said, “Almost all current sensor protein probes are based on conformational changes. In contrast, the fluorescence quenching mechanism used in this study expands the possibilities for the development of novel protein sensor probes.”

The paper is published in the journal Scientific Reports.