In a study published today in Nature Communications, a research team led by Ken Shepard, professor of electrical engineering and biomedical engineering at Columbia Engineering, and Lars Dietrich, assistant professor of biological sciences at Columbia University, has demonstrated that integrated circuit technology, the basis of modern computers and communications devices, can be used for a most unusual application—the study of signaling in bacterial colonies.
The development of colony biofilms by Pseudomonas aeruginosa is affected by redox-active compounds called phenazines. A phenazine-null mutant forms a hyperwrinkled colony with prominent spokes, while wild-type colonies are more constrained and smooth.
Credit: Hassan Sakhtah, Columbia University
They have developed a chip based on complementary metal-oxide-semiconductor (CMOS) technology that enables them to electrochemically image the signaling molecules from these colonies spatially and temporally. In effect, they have developed chips that "listen" to bacteria.
"This is an exciting new application for CMOS technology that will provide new insights into how biofilms form," says Shepard. "Disrupting biofilm formation has important implications in public health in reducing infection rates."
The researchers, who include PhD students Dan Bellin (electrical engineering) and Hassan Sakhtah (biology), say that this is the first time integrated circuits have been used for such an application—imaging small molecules electrochemically in a multicellular structure. While optical microscopy techniques remain paramount for studying biological systems (using photons allows for relatively non-invasive interaction to the biological system being studied), they cannot directly detect critical components of physiology, such as primary metabolism and signaling factors.
The team thought there might be a better way to directly detect small molecules through techniques that employ direct transduction to electrons, without using photos as an intermediary. They made an integrated circuit, a chip that, Shepard says, is an "'active' glass slide, a slide that not only forms a solid-support for the bacterial colony but also 'listens' to the bacteria as they talk to each other."
Cells, Dietrich explains, mediate their physiological activities using secreted molecules. The team looked specifically at phenazines, which are secreted metabolites that control gene expression. Their study found that the bacterial colonies produced a phenazine gradient that, they say, is likely to be of physiological significance and contribute to colony morphogenesis.
"This is a big step forward," Dietrich continues. "We describe using this chip to 'listen in' on conversations taking place in biofilms, but we are also proposing to use it to interrupt these conversations and thereby disrupt the biofilm. In addition to the pure science implications of these studies, a potential application of this would be to integrate such chips into medical devices that are common sites of biofilm formation, such as catheters, and then use the chips to limit bacterial colonization."
The next step for the team will be to develop a larger chip that will enable larger colonies to be imaged at higher spatial and temporal resolutions.
"This represents a new and exciting way in which solid-state electronics can be used to study biological systems," Shepard adds. "This is one of the many emerging ways integrated circuit technology is having impact in biotechnology and the life sciences."
The study was supported by the National Institutes of Health and the National Science Foundation.
Holly Evarts | EurekAlert!
Penn first in world to treat patient with new radiation technology
22.09.2017 | University of Pennsylvania School of Medicine
Skin patch dissolves 'love handles' in mice
18.09.2017 | Columbia University Medical Center
At the productronica trade fair in Munich this November, the Fraunhofer Institute for Laser Technology ILT will be presenting Laser-Based Tape-Automated Bonding, LaserTAB for short. The experts from Aachen will be demonstrating how new battery cells and power electronics can be micro-welded more efficiently and precisely than ever before thanks to new optics and robot support.
Fraunhofer ILT from Aachen relies on a clever combination of robotics and a laser scanner with new optics as well as process monitoring, which it has developed...
Plants and algae use the enzyme Rubisco to fix carbon dioxide, removing it from the atmosphere and converting it into biomass. Algae have figured out a way to increase the efficiency of carbon fixation. They gather most of their Rubisco into a ball-shaped microcompartment called the pyrenoid, which they flood with a high local concentration of carbon dioxide. A team of scientists at Princeton University, the Carnegie Institution for Science, Stanford University and the Max Plank Institute of Biochemistry have unravelled the mysteries of how the pyrenoid is assembled. These insights can help to engineer crops that remove more carbon dioxide from the atmosphere while producing more food.
A warming planet
Our brains house extremely complex neuronal circuits, whose detailed structures are still largely unknown. This is especially true for the so-called cerebral cortex of mammals, where among other things vision, thoughts or spatial orientation are being computed. Here the rules by which nerve cells are connected to each other are only partly understood. A team of scientists around Moritz Helmstaedter at the Frankfiurt Max Planck Institute for Brain Research and Helene Schmidt (Humboldt University in Berlin) have now discovered a surprisingly precise nerve cell connectivity pattern in the part of the cerebral cortex that is responsible for orienting the individual animal or human in space.
The researchers report online in Nature (Schmidt et al., 2017. Axonal synapse sorting in medial entorhinal cortex, DOI: 10.1038/nature24005) that synapses in...
Whispering gallery mode (WGM) resonators are used to make tiny micro-lasers, sensors, switches, routers and other devices. These tiny structures rely on a...
Using ultrafast flashes of laser and x-ray radiation, scientists at the Max Planck Institute of Quantum Optics (Garching, Germany) took snapshots of the briefest electron motion inside a solid material to date. The electron motion lasted only 750 billionths of the billionth of a second before it fainted, setting a new record of human capability to capture ultrafast processes inside solids!
When x-rays shine onto solid materials or large molecules, an electron is pushed away from its original place near the nucleus of the atom, leaving a hole...
19.09.2017 | Event News
12.09.2017 | Event News
06.09.2017 | Event News
25.09.2017 | Power and Electrical Engineering
25.09.2017 | Health and Medicine
25.09.2017 | Physics and Astronomy