JTS-100: A step change in accurately measuring photosynthesis

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Photosynthesis is the process by which virtually all energy and organic matter enters the biosphere and as such is vital for marine and terrestrial food webs. These food webs form the basis of our own food supply. In producing this food, it sucks CO2 from the atmosphere whilst producing ALL of the oxygen that ALL complex life depends on. It is a regulator of the Earth's climate, through sequestration of atmospheric CO2 and is therefore the greatest form of natural capital we possess in the fight against climate change. A synthetic catalyst that mimics the activity of photosynthesis would surely solve humanity's energy crisis.Photosynthesis makes use of a type of electronic circuit inside cells that rips electrons from water and donates them to CO2 to form sugars. The electronic circuit is composed of a series of protein complexes and small molecules that act as "transistors". One of these "transistors" is called photosystem II, and we can measure its activity by diagnostic signatures in fluorescence it emits when it is active. We can also measure this activity robotically with high spatial and temporal resolution in automated marine submersibles, through drones over rainforests and even from space using satellites. Together these data are being used by scientists to give a global picture of photosynthesis, its distribution and extent, and help us understand the environmental factors that shape it. The major challenge, however, is relating photosystem II activity to true measures of photosynthesis given that photosystem II measurements can both under- and over-estimate actual photosynthetic rates. A key source of this error is the activity of some of the other "transistors" downstream of photosystem II. Our understanding of these activities is in its infancy mainly due to a lack of technologies to measure them. These technologies are essential if we are to predict how the Earth will respond to the increasing levels of CO2 in our atmosphere. Such predictions are made using climate models which require accurate measurements of critical parameters like photosynthetic rates as their input. It is now possible to measure the activity of these "transistors" biophysically using the JTS-100 instrument. The main functions of this instrument are to allow researchers to elucidate new facets of photosynthesis, particularly the discovery, activity and regulation of these "transistors". These discoveries will feed back into understanding the global extent of photosynthesis in plants, algae and cyanobacteria and how they respond to environmental change.