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Sujith Puthiyaveetil and Steve McKenzie look at a plant thylakoid in a lab at the biochemistry building at Purdue University. Photo Credit: Purdue Agricultural Communications/Joshua Clark |
Cyanobacteria began contributing oxygen to Earth’s mostly noxious atmosphere more than 2 billion years ago. The photosystem II protein complex now shared by various lineages of cyanobacteria, algae and land plants has served as a major site of oxygen production throughout the history of life on Earth ever since.
Ironically, receiving too much light can damage photosystem II and erode the photosynthetic efficiency of plants. Purdue University biochemists Steven McKenzie and Sujith Puthiyaveetil have gleaned new, long-hidden details about how photosystem II repairs itself. McKenzie and Puthiyaveetil’s findings have been published in the journal Plant Communications.
“The photosystem II splits water and extracts electrons and protons, leaving oxygen as a by-product. Photosystem II thereby powers life on Earth,” said Puthiyaveetil, associate professor of biochemistry. Even so, “it’s still fairly poorly understood how these huge protein complexes that use light energy to produce oxygen are able to be repaired and maintained so efficiently across different lineages of plants, algae and cyanobacteria.”