Scientists accidentally discover photosynthesis doesn’t work exactly like we thought it did

Published

2 years ago

April 1, 2023

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Photosynthesis is one of the most important chemical processes on Earth. (Image credit: Shutterstock)

One of the most well-studied chemical processes in nature, photosynthesis, may not work quite how we thought it did, scientists have accidentally discovered.

Photosynthesis is the process by which plants, algae and some bacteria convert carbon dioxide and water into oxygen and sugars to use as energy. To do this, the organisms use sunlight to oxidize, or take electrons from, water; and reduce, or give electrons to, carbon dioxide molecules. These chemical reactions require photosystems — protein complexes that contain chlorophyll, a pigment that absorbs light and gives plant leaves and algae their green color — to transfer electrons between different molecules.

In the new study, published March 22 in the journal Nature (opens in new tab) , researchers used a new technique, known as ultrafast transient absorption spectroscopy, to study how photosynthesis works at a timescale of one quadrillionth of a second (0.000000000000001 second) for the first time. The team was initially trying to figure out how quinones — ring-shaped molecules that can steal electrons during chemical processes — impact photosynthesis. But instead, the researchers found that electrons could be released from photosystems much earlier during photosynthesis than scientists previously believed was possible.

“We thought we were just using a new technique to confirm what we already knew,” study co-author Jenny Zhang (opens in new tab) , a biochemist specializing in photosynthesis at the University of Cambridge in England, said in a statement (opens in new tab) . “Instead, we found a whole new pathway, and opened the black box of photosynthesis a bit further.”

Related: New ‘artificial’ photosynthesis is 10x more efficient than previous attempts

Photosynthetic algae viewed under the microscope. Their green color is the result of the pigment chlorophyll found inside photosystems. (Image credit: Shutterstock)

Two photosystems are used during photosynthesis: photosystem I (PSI) and photosystem II (PSII). PSII primarily provide electrons to PSI by taking them from water molecules: PSI then further excites the electrons before releasing them to eventually be given to carbon dioxide to create sugars, via a series of complex steps.

Past research had suggested that the protein scaffolding in PSI and PSII was very thick, which helped to contain electrons within them before being passed on to where they were needed. But the new ultrafast spectroscopy technique revealed that the protein scaffolding was more “leaky” than expected and that some electrons could escape from the photosystems almost immediately after light was absorbed by the chlorophyll within the photosystems. These electrons could therefore reach their destinations faster than expected.

“The new electron transfer pathway we found here is completely surprising,” Zhang said. “We didn’t know as much about photosynthesis as we thought we did.”

The electron leaking was observed in both isolated photosystems and within “living” photosystems inside cyanobacteria.RELATED STORIES—Plant leaves spark with electricity during thunderstorms — and that could be altering our air quality in unpredictable ways

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In addition to rewriting what we know about photosynthesis, the discovery opens up new avenues for future research and biotechnology applications. The team believes that by “hacking” photosynthesis to release more of these electrons at earlier stages, the process could become much more efficient, which could help produce plants that are more resistant to sunlight or be replicated artificially to create renewable energy sources to help combat climate change, according to the statement. However, much more research is needed before this can happen.

“Many scientists have tried to extract electrons from an earlier point in photosynthesis, but said it wasn’t possible because the energy is so buried in the protein scaffold,” Zhang said. “The fact that we can [potentially] steal them at an earlier process is mind-blowing.”

Technology

Amazon CEO Jassy says AI will lead to ‘fewer people doing some of the jobs’ that get automated

Published

2 hours ago

July 1, 2025

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Amazon CEO Jassy says AI will lead to 'fewer people doing some of the jobs' that get automated

AI will change the workforce, says Amazon CEO Andy Jassy

Amazon CEO Andy Jassy said the rapid rollout of generative artificial intelligence means the company will one day require fewer employees to do some of the work that computers can handle.

“Like with every technical transformation, there will be fewer people doing some of the jobs that the technology actually starts to automate,” Jassy told CNBC’s Jim Cramer in an interview on Monday. “But there’s going to be other jobs.”

Even as AI eliminates the need for some roles, Amazon will continue to hire more employees in AI, robotics and elsewhere, Jassy said.

Earlier this month, Jassy admitted that he expects the company’s workforce to decline in the next few years as Amazon embraces generative AI and AI-powered software agents. He told staffers in a memo that it will be “hard to know exactly where this nets out over time” but that the corporate workforce will shrink as Amazon wrings more efficiencies out of the technology.

It’s a message that’s making its way across the tech sector. Salesforce CEO Marc Benioff last week claimed AI is doing 30% to 50% of the work at his software vendor. Other companies such as Shopify and Microsoft have urged employees to adopt the technology in their daily work. The CEO of Klarna said in May that the online lender has managed to shrink its headcount by about 40%, in part due to investments in AI and natural attrition in its workforce.

Jassy said on Monday that AI will free employees from “rote work” and “make all our jobs more interesting,” while enabling staffers to invent better services more quickly than before.

Amazon and other tech companies have also been shrinking their workforces through rolling layoffs over the past several years. Amazon has cut more than 27,000 jobs since the start of 2022, and it’s announced smaller, more targeted layoffs in its retail and devices units in recent months.

Amazon shares are flat so far this year, underperforming the Nasdaq, which has gained 5.5%. The stock is about 10% below its record reached in February, while fellow megacaps Meta, Microsoft and Nvidia are all trading at or very near record highs.

WATCH: Jassy says robots that will eventually do delivery and transportation

Over time we will have robots that will do delivery and transportation, says Amazon CEO Andy Jassy

Politics

PM faces threat of major rebellion during key vote today

Published

2 hours ago

July 1, 2025

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PM faces threat of major rebellion during key vote today

Sir Keir Starmer continues to face the threat of a major rebellion during a key vote on welfare reforms later – despite making last-minute concessions to disgruntled Labour MPs.

Work and Pensions Secretary Liz Kendall has confirmed that all existing claimants of the personal independence payment (PIP), the main disability benefit, will be protected from changes to eligibility.

The combined value of the standard Universal Credit allowance and the health top-up will rise “at least in line with inflation” every year of this parliament.

And an additional £300m for employment support for sick and disabled people in 2026 has been announced, which will rise every year after.

Ms Kendall has also promised that a consultation into PIP – “co-produced” with disabled people – will be published next autumn.

She said the U-turn on welfare cuts will cost taxpayers about £2.5bn by 2030 – less than half the £4.8bn the government had expected to save with its initial proposals.

Modelling by Ms Kendall’s own department, released yesterday, suggested the proposals would push 150,000 more people into poverty by 2030, down from the 250,000 estimated under the original plan.

But after announcing the U-turns, Labour MPs were still publicly saying they could not back the plans as they do not go far enough to allay their concerns.

Disabilities minister Stephen Timms would not say he was “confident” the proposals would pass the Commons when asked on Sky News’ Politics Hub with Sophy Ridge.

“We’ve got a very strong package, I certainly hope it passes,” he replied.

A total of 86 charities united yesterday to call on MPs to reject the reforms, saying they will harm disabled people and calling it “a political choice”.

The likes of Oxfam, Child Action Poverty Group, Mind and Shelter said the bill has been brought to a vote without consulting disabled people and without any assessment “of its impact on health and employment outcomes”.

When asked to name “a single” disability organisation in favour of the reforms, Ms Kendall declined to do so.

Several Labour MPs indicated they would still vote against the changes, leaving the government in the dark over how big a rebellion it still may face.

Ms Kendall tried to allay their fears, telling MPs: “I believe we have a fair package, a package that protects existing claimants because they’ve come to rely on that support.”

Richard Burgon presented a petition to parliament yesterday evening against the cuts, signed by more than 77,000 people.

Several Labour MPs questioned why the vote was going ahead before the review into PIP is published – including Rachael Maskell, who said she could not “countenance sick and disabled people being denied support” and added: “It is a matter of conscience.”

Connor Naismith said the concessions “undoubtedly improve efforts to secure welfare reform which is fair”, but added: “Unfortunately, I do not believe these concessions yet go far enough.”

Nadia Whittome accused the government of “ignoring” disabled people and urged ministers to go “back to the drawing board”.

Ian Byrne told the Commons he will vote against the “cruel cuts” to disability benefits because the “so-called concessions go nowhere near far enough”.

The vote will take place this evening, with coverage on Sky News’ Politics Hub live blog and on TV.

World

Benjamin Netanyahu to meet Donald Trump next week amid calls for Gaza ceasefire

Published

2 hours ago

July 1, 2025

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Benjamin Netanyahu to meet Donald Trump next week amid calls for Gaza ceasefire

Israeli Prime Minister Benjamin Netanyahu will be meeting Donald Trump next Monday, according to US officials.

The visit on 7 July comes after Mr Trump suggested it was possible a ceasefire in Gaza could be reached within a week.

On Sunday, he wrote on social media: “MAKE THE DEAL IN GAZA. GET THE HOSTAGES BACK!!!”

At least 60 people killed across Gaza on Monday, in what turned out to be some of the heaviest attacks in weeks.

According to the Hamas-run health ministry, 56,500 people have been killed in the 20-month war.

The visit by Mr Netanyahu to Washington has not been formally announced and the officials who said it would be going ahead spoke on condition of anonymity.

An Israeli official in Washington also confirmed the meeting next Monday.

White House Press Secretary Karoline Leavitt said the administration was in constant communication with the Israeli government.

She said Mr Trump viewed ending the war in Gaza and returning remaining hostages held by Hamas as a top priority.

The war in Gaza broke out in retaliation for Hamas’ 7 October 2023 attacks on southern Israel that killed 1,200 people and saw a further 250 taken hostage.

An eight-week ceasefire was reached in the final days of Joe Biden’s US presidency, but Israel resumed the war in March after trying to get Hamas to accept new terms on next steps.

Talks between Israel and Hamas have stalled over whether the war should end as part of any ceasefire.