Why the abundance of RuBisCO in photosynthetic cells may come from its inefficiency

Rubisco, the crucial enzyme powering photosynthesis

Photosynthesis is the crucial process by which plants absorb sunlight, take up water, and breathe in carbon dioxide, prompting chemical reactions that result in the byproducts sugar and oxygen. A key enzyme, rubisco, is responsible for it all, but it is inefficient. This video explores the key protein and reveals fascinating facts about oxygen and photosynthesis.

How MIT researchers have used genetic mutations to improve photosynthesis efficiency

Recognizing that RuBisCO—a protein that binds carbon dioxide to other compounds to produce the building blocks of organic molecules—often mistakenly binds oxygen, scientists performed directed evolution experiments to modify the geometry of a bacterial version of the protein to cause it to preferentially interact with carbon dioxide over oxygen.

Nearly half the oxygen we breathe comes from photosynthetic plankton, not plants

Although the Amazon Rainforest is considered the "lungs of the Earth," it only produces 20% of the planet's oxygen, while phytoplankton, or microalgae, generate more than twice as much, despite making up less than 1% of the total mass of photosynthetic organisms on the planet. Through photosynthesis, microalgae also absorb up to 40% of global carbon emissions.

The research pipelines being explored by the RIPE Project to improve photosynthesis

These include engineering plants with faster stomata, which would allow photosynthesis to resume more quickly amid fluctuations in available light due to clouds or shading from other plants, and resolving bottlenecks in the regeneration of RuBP, the molecule to which carbon dioxide is fixed during photosynthesis to initiate the Calvin cycle. (Some readers may experience a paywall.)

An explanation of the Calvin cycle, including why it needs to run six times to create glucose

Each run of this second phase of photosynthesis begins with a five-carbon molecule called RuBP, which gains an additional carbon atom when carbon dioxide (CO₂) is attached. Across six cycles, the six six-carbon molecules—36 carbon atoms in total—are processed into 12 three-carbon sugars, which can be used to generate glucose, and six RuBP molecules, enough for each cycle to restart.

A look at anoxygenic photosynthetic bacteria, which do not produce oxygen

Rather than using water to produce organic compounds and release oxygen, purple and green sulfur bacteria take up hydrogen sulfide, carbon dioxide, and light to produce water, elemental sulfur, and a carbohydrate. Other organisms can take up various molecules and elements, such as iron, which can replenish the electrons in pigments involved in light-dependent reactions.

How artificial photosynthesis can help make plastics and fuels using sunlight

These systems link a molecular light absorber to a catalyst that can synthesize fuels—such as ethanol—and ethylene, a precursor to plastics, in a carbon-neutral manner. Because these byproducts have greater energy concentrations than the carbohydrates produced by photosynthetic organisms, research is ongoing to engineer the necessary catalysts.

How greenhouse gases and climate change impact the efficiency of photosynthesis

A review in the Journal of Experimental Botany found that higher temperatures reduce the efficiency of enzymes involved in photosynthesis and impair a plant's ability to control water loss and regulate carbon dioxide uptake. While increased carbon dioxide levels are understood to accelerate plant growth by boosting photosynthesis, researchers suggest these effects more than offset the potential gain.

Explore the efficiency of photosynthesis under various conditions

In this simulation, users can track how the cellular concentrations of ATP, NADPH, glucose, and oxygen vary over time in response to changes in temperature, acidity, carbon dioxide concentration, and the properties of incoming light. Through multiple trials, users can identify the optimal conditions for photosynthetic reactions.

Carbon sinks absorb more greenhouse gases than they produce

The largest on Earth are oceans, which capture 25% of all carbon emissions and 90% of excess atmospheric thermal radiation while generating half of the world's oxygen. Wildfires and deforestation have reduced forests' net sink capacity, though fungi are believed to capture and store over a third of global carbon emissions.

Early Earth lifeforms likely made energy via mineral reactions, not sunlight

Earth's initial atmosphere was filled with carbon dioxide, methane, and water, with most oxygen locked away in the rocky crust. Over time, bacteria evolved to slowly release that oxygen into the atmosphere by breaking down rock.

Imagining if humans could perform photosynthesis and how it would change our anatomy

Since chloroplasts reflect green light, becoming photosynthetic would give our skin a green appearance. Because photosynthesis has efficiencies of only 5% to 9%, and humans burn 2,000 Calories daily compared to about 200 burned by a tree, becoming photosynthetic would also require us to adopt a less active, sun-filled lifestyle.

The Google Doodle honoring Jan Ingenhousz, who discovered oxygenic photosynthesis

Born in 1730, the Dutch scientist expanded on existing knowledge that plants produce and absorb gases in his 1779 paper, which detailed that light was necessary for the biochemical processes that produce oxygen in plant leaves. He also identified that all parts of plants produce carbon dioxide at night.

Despite its potential, CRISPR still fails 15% of the time

Biochemists from UIC found that persistent Cas9 binding to double-strand breaks impacts DNA repair efficiency and the effectiveness of the gene editing tool. RNA polymerase collisions also dislodge Cas9, which affects the efficiency of the tool.

Exposed concrete led to oxygen depletion within Biosphere 2

Instead of being absorbed by plants through photosynthesis to produce oxygen, significant amounts of carbon dioxide were taken up by the calcium hydroxide in the concrete, trapping the oxygen in calcium carbonate and water. This concrete was sealed before the start of the second B2 mission.

Explore the water footprint of producing various proteins, fruits, and vegetables

This interactive gallery highlights the various types of water behind the production of biofuels, foods, and materials such as cotton. Diets high in bovine meat, whose production requires 15,415 liters of water per kilogram (1,847 gallons per pound), are among the most water-intensive, whereas every kilogram of vegetables uses 322 liters of water (39 gal/lb) to produce.

Lining up every microbe on Earth would stretch to about 105,000 light-years

There are about 10²⁷ such organisms on the planet, many of which are adapted to produce energy through uncommon reactions in unconventional environments, such as within rocks or near volcanoes on the ocean floor. Studies of these organisms have reframed astrobiologists' search for life beyond Earth by broadening the parameters under which life can exist.

Cells cannot grow forever due to escalating inefficiency in transporting chemicals

As cells get larger, their volume grows much faster than the surface area through which nutrients and waste products pass, creating a bottleneck that eventually causes cells to die. This forces nearly all organisms visible to the naked eye to comprise enormous numbers of smaller cells, such as the approximately 30 trillion found in the average adult human.

View the industrial applications of extremozymes, from food safety to antibiotic production

Extremophiles possess unique enzymes and organic molecules that have enabled them to adapt to and thrive in otherwise lethal environments. Because these conditions resemble those found in various areas of manufacturing and production plants, these organisms and their macromolecules can optimize industrial processes where conventional catalysts would lose their ability to speed up reactions.

How geometry and uneven charge distribution make some molecules greenhouse gases

Molecules vibrate and rotate with different frequencies based on their elemental composition and shape, which can produce uneven distributions of electrons, as seen in carbon dioxide and water. The resulting unbalanced electric field can interact with electromagnetic waves of the same frequency, causing the molecule to absorb the radiation.

How a black market for banned refrigerants still threatens ozone recovery and climate progress

Despite the Montreal Protocol's success, illegal trade in chlorofluorocarbons, hydrochlorofluorocarbons, and hydrofluorocarbons persists. Driven by high profits and weak enforcement, smugglers supply banned refrigerants, causing significant ozone depletion and greenhouse gas emissions equivalent to billions of tons of carbon dioxide.

Cryptocurrency is reshaping finance, but its environmental impact often sparks debate

Behind the scenes, mining operations consume vast amounts of energy, comparable to the emissions of small nations. What drives this surprising environmental footprint, and can the industry evolve?

Peptides may have predated ribosomes—the cell's protein factory

Some scientists have hypothesized that peptides and RNA molecules may have coevolved as a single, mixed "chimeric" molecule, fueling the beginning of protein production and predating a primitive version of the ribosome. All life today uses ribosomes to make peptides. (Some users may experience a paywall.)

DNA computing allows for storage and processing of massive amounts of data

Although costly and less efficient for simpler tasks, as of 2025, DNA could hold 455 exabytes of data with near limitless parallel computation potential in small data centers. Every movie ever made would fit inside the volume of a single sugar cube.

Comparing bioremediation with other treatment techniques, at three levels of complexity

Physical manipulation, such as collecting and moving contaminated material to a landfill, or chemical applications, which use strong, expensive substances and produce harmful byproducts, can be costly. While bioremediation leverages naturally occurring degradation processes that can be augmented without disrupting impacted ecosystems, these processes may be less effective in environments that bioremediation organisms are not adapted to.

Coral reefs get their colors from zooxanthellae—microorganisms that line corals' digestive tracts and provide them with sugars in exchange for a home within this protective tissue.

Scientists testing how climate change affects plants found, in a years-long simulation study, that poison ivy grew 70% faster with the resulting extra carbon dioxide.

Visualize how CRISPR-Cas9—a type of immune system used by single-celled organisms to attack invasive viruses—targets and makes precise changes to a gene's DNA.

As of 2025, the most cited papers in science include a review of graphene, methods to improve image recognition, streamlining electron density calculations, and optimizing protein studies.

Watch how deep-sea mining equipment collects and processes polymetallic nodules—metal-rich, potato-shaped rocks—from the ocean floor and creates environmentally damaging plumes of sediments.

Indefinite cloning of some endangered species may not sustain their longevity because cloning success rates decrease as genetic mutations accumulate.

How fusion—which releases energy when two lighter atoms combine to form a heavier atom—differs from fission

See how each of the more than two million known species relates to each other—and to common ancestors—in this zoomable tree of life.

Scientists can determine Earth's past climate conditions by analyzing air trapped in microscopic bubbles within ice cores—columns of compressed snow layers that build up over hundreds of thousands of years.

Some renewable energy sources may weaken the resiliency of electric grids by removing outage buffers provided by coal- and natural gas-fired plants, which provide the system with more time to find a new power source if a plant goes down.

Bone marrow (soft tissue found inside certain bones) generates roughly 500 billion new blood cells each day

Stars appear to twinkle because turbulence in the motion of molecules in Earth's atmosphere causes light to bend and wiggle rapidly on its way to the surface—a phenomenon called scintillation.

The price of gas is a composite made up of several different factors, with the federal gas tax making up less than 20% of what drivers pay at the pump.

The use of fungi to detoxify land and water—a process known as mycoremediation—has been used to clean up natural resources affected by the 2025 California wildfires.

Studies suggest when you sleep is as important as how much you get, and syncing with your circadian rhythms may lead to less fatigue and improved long-term health outcomes

The syncytiotrophoblast is the outer layer of the placenta and the largest human cell, spanning an area about twice that of a king-sized bedsheet.

Louisiana's 'Cancer Alley' is infamous for having some of the highest industrial pollution, toxic air emissions, and cancer risks in the US.

Up to a million Girl Scouts sell about 200 million cookie boxes every spring, generating $800 million, largely because refusing a child is frowned upon

Budweiser stores yeast derived from the original 1800s strain in a secret bunker, which only the Head of Yeast Management can access—not even the CEO

How Amazon operates a 'flywheel' business model, a self-reinforcing cycle that drives continuous growth

Most of the observable universe's volume consists of voids and supervoids—enormous regions of space with little to no galaxies, stars, or light.

Dorothy's famous entrance into Oz in 'The Wizard of Oz' relied on analog tricks, including a body double and sepia-toned paint, as much as it did on technology

The American cockroach is actually from Africa, an apparent hitchhiker aboard ships carrying enslaved people, with evidence suggesting the bug may have arrived in the New World as early as the 1600s.

Double world record holder Hunter Ewen helped conquer his fear of balloons, called globophobia, by training to win Guinness World Record titles for balloon inflation.

Stanford built a Google Maps for the Roman Empire, revealing how much it cost to travel in the ancient world