It has long been known that a strain of tuberculosis bacteria can generate electricity from hydrogen in the air. Scientists have now figured out how to do this.
Researchers studying a relative of the bacterium that causes leprosy and tuberculosis have found an enzyme that converts hydrogen into electricity, and they believe it could be used to generate a new, clean energy source almost from the air.
The bacterium Mycobacterium smegmatis uses the enzyme Huc to extract energy from atmospheric hydrogen, enabling it to live in harsh, nutrient-poor environments.
An Oxygen Insensitive Enzyme HUC
Here, we describe the structure and mechanism of the Mycobacterium smegmatis hydrogenase Huc using cryo-electron microscopy. Huc supports the hydrogenation of the respiratory electron carrier menaquinone in H.2It is a highly effective, oxygen-insensitive enzyme that binds to the oxidation of
Today, scientists claim to have discovered a new energy source that could be used to power a variety of small portable power tools by extracting and investigating the enzyme.
Lead author Rhys Grinter, a microbiologist at Monash University in Australia, told Live Science via e-mail that the team used the air to power a power supply containing Huc using air, including biometric sensors, environmental monitors, digital clocks, calculators and simple computers. He said he envisions it being able to run a variety of small portable devices.
Huc produces more electric current when more concentrated hydrogen is introduced. This means it could be used in fuel cells to power increasingly sophisticated devices such as smartwatches, cell phones, more portable complex computers and possibly even an automobile.
M. smegmatis is a non-pathogenic, fast-growing bacterium frequently used in laboratories to investigate the cell wall composition of its disease-causing close relative, Mycobacterium tuberculosis. M. smegmatis, a soil microbe widely found worldwide, has long been known to convert traces of hydrogen in the air into energy to survive in the harshest environments, such as Antarctic soils, volcanic craters, and the deep oceans, where little other fuel is available.
Up to this point, however, it remained unclear how M. smegmatis achieved this.
To examine the chemistry underlying M. smegmatis' amazing abilities, the researchers used chromatography, a laboratory technique that allows researchers to separate the components of a mixture, to first isolate the enzyme Huc responsible for the process.
They then studied the enzyme's atomic structure using cryo-electron microscopy, a method for which its developers won the 2017 Nobel Prize in Chemistry. The researchers studied the enzyme's atomic structure and the electrical pathways it uses to transport electrons so that they blast electrons to generate a current on a frozen sample of Huc collected from M. smegmatis.
The team found that Huc has an active site in its core, a structure that houses charged nickel and iron ions. Once hydrogen molecules enter the active site, they lose their electrons because they are trapped between nickel and iron ions. To create a current, the enzyme then moves these electrons along a current.
According to Grinter, electrons are taken up by Huc (specifically the nickel ion) and delivered to its surface by a molecular wire made up of clusters of iron and sulfur ions. “If we immobilize the huc on an electrode, electrons can flow from the enzyme surface into an electrical circuit and generate electricity.”
Further research showed that the isolated Huc enzyme could be stored for a long time, withstand freezing or heating to 80 degrees Celsius, and could consume hydrogen in concentrations as small as 0,00005% of the hydrogen found in our air. The researchers suggest that these properties, along with the microbe's ubiquity and ease of growth, could make the enzyme a primary choice for a power source in organic batteries.
According to Grinter, the amount of hydrogen in the air that Huc can extract as energy is practically infinite. “Due to the low levels of hydrogen in the air, only a small amount of electricity can be produced. Huc can then only be used for devices that need a small amount of power over a long period of time. Huc can also be used in fuel cells that provide higher concentrations of hydrogen.”
Source: Live Science
Günceleme: 18/03/2023 23:38