Light-Controlled Algae Starch Storage Offers New Path to Cut Greenhouse Gases.

Researchers have discovered a novel method to control starch storage in algae by manipulating their response to light—an advancement that could play a key role in reducing greenhouse gas emissions. The study, published in Nature Communications and led by Associate Professor Dimitris Petroutsos from Uppsala University, highlights how altering a blue-light-sensitive pathway in algae enhances starch accumulation without hindering their growth or photosynthesis.

Algae, like other photosynthetic organisms, convert sunlight and carbon dioxide into carbohydrates. In green algae such as Chlamydomonas reinhardtii, these carbohydrates are used for immediate energy or stored as starch. Traditionally, increased starch levels in algae have been achieved by depriving them of nutrients—a method that often compromises their growth.

This new research shifts the focus to light, specifically the impact of blue light. The scientists found that a protein known as phototropin, which senses blue light, triggers a signaling cascade that suppresses starch buildup by regulating essential metabolic genes. In contrast, red light promotes starch storage. By disabling phototropin in genetically modified algae, the team increased starch content from 5% to 25% of the algae's dry weight, all without affecting photosynthetic efficiency or overall growth.

The ability to fine-tune starch production using light has significant implications across multiple sectors. In the field of biofuels, starch-dense algae can be converted into bioethanol and other energy sources more efficiently. In sustainable agriculture, microalgae are already used as feed supplements; increasing their starch content could enhance their nutritional value and effectiveness as both livestock feed and soil enhancers. Additionally, in the area of carbon capture, regulating starch accumulation could optimize how algae sequester carbon dioxide, contributing to efforts to mitigate climate change.

“This represents a major leap beyond traditional methods that rely on environmental stress,” said Petroutsos. “By blocking the phototropin signaling pathway, we can increase starch storage in a much more controlled and sustainable way.”

This discovery marks a promising step toward utilizing algae not just as a resource, but as a tool in global environmental and energy solutions.

Source:https://phys.org/news/2025-04-starch-algae-greenhouse-gases.html

This is non-financial/medical advice and made using AI so could be wrong.