We use cookies to understand how you use our site and to improve your experience. This includes personalizing content and advertising. To learn more, click here. By continuing to use our site, you accept our use of cookies. Cookie Policy.

Features Partner Sites Information LinkXpress
Sign In
Advertise with Us
LGC Clinical Diagnostics

Download Mobile App


ATTENTION: Due to the COVID-19 PANDEMIC, many events are being rescheduled for a later date, converted into virtual venues, or altogether cancelled. Please check with the event organizer or website prior to planning for any forthcoming event.

Next-Generation Whole-Cell Biosensors May Provide New Approach to Diagnostics

By LabMedica International staff writers
Posted on 08 Jun 2015
Print article
Image: Newly designed bacteria with synthetically rewired genetic circuitry act as bactosensors to detect abnormal glucose levels in urine of diabetes patients (Photo courtesy of Chris Bickel and the journal Science).
Image: Newly designed bacteria with synthetically rewired genetic circuitry act as bactosensors to detect abnormal glucose levels in urine of diabetes patients (Photo courtesy of Chris Bickel and the journal Science).
Image: Illustration of principle for using modified, “programmed” bacteria as “bactodetectors” of molecular markers for medical diagnosis (Photo courtesy of J. Bonnet and INSERM).
Image: Illustration of principle for using modified, “programmed” bacteria as “bactodetectors” of molecular markers for medical diagnosis (Photo courtesy of J. Bonnet and INSERM).
Researchers have developed the first programmable bacterial cells for medical diagnosis with improved computing and amplification capacity that could enable earlier clinical detection of various pathological biomarkers in urine or blood.

Several hurdles have limited the application of whole-cell biosensors as analytical clinical tools, primarily their unreliable operation in complex samples and low signal-to-noise ratio. Teams led by Jerome Bonnet (INSERM, CNRS; Montpellier University; Montpellier, France), Franck Molina (SysDiag, CNRS; Montpellier, France), in association with teams led by Eric Renard (Montpellier Regional University Hospital; Montpellier, France) and Drew Endy (Stanford University; Standford, CA, USA), have transformed bacteria into diagnostic agents by inserting the equivalent of a computer program into their DNA. These “bactosensors” with genetically encoded digital amplifying genetic switches can detect clinically relevant molecular markers. They perform signal digitization and amplification, multiplexed signal processing via Boolean logic gates, and data storage.

In vitro diagnostic (IVD) tests are generally noninvasive and simple, but some are complex, requiring sophisticated technologies often available only in central laboratories. Living cells can detect, process, and respond to many signals. Provided with an appropriate “program” they can accomplish diagnostic tasks. To do this, Jerome Bonnet’s team at had the idea to apply concepts from synthetic biology derived from electronics to construct genetic systems to “program” living cells like a computer.

As a central component of modern electronic instruments (including calculators and smartphones), the transistor acts both as a switch and a signal amplifier. In informatics, several transistors are combined to construct “logic gates” that respond to different signal combinations according to a predetermined logic. For example, a dual input “AND” logic gate will produce a signal only if both of two input signals are present. At Standford University Jerome Bonnet had previously invented a genetic transistor named the “transcriptor.” Inserting transcriptors into bacteria can transform them into calculators, where electrical signals used in electronics are replaced by molecular signals that control gene expression. It is thus possible to reprogram the cells by implanting simple genetic “programs” as sensor modules that enable cells to respond to specific combinations of molecules.

The team now applied this new technology to detect disease “signals” in clinical samples. The transcriptor amplification ability was used to detect biomarkers even at very small amounts, and the test results were successfully stored in the bacterial DNA for several months. Thus, the semi-synthetic cells acquired the ability to perform different functions based on the presence of several markers, opening the way to more accurate diagnostic tests that rely on detection of molecular “signatures” using different biomarkers.

As a proof-of-concept clinical experiment, the transcriptor was connected to a bacterial system that responds to glucose and successfully detected the abnormal levels of glucose in urine of diabetic patients.

“We have standardized our method, and confirmed the robustness of our synthetic bacterial systems in clinical samples. We have also developed a rapid technique for connecting the transcriptor to new detection systems. All this should make it easier to reuse our system,” said first author Alexis Courbet, “Our work is presently focused on the engineering of artificial genetic systems that can be modified on demand to detect different molecular disease markers,” said Jerome Bonnet.

The study, by Courbet A, et al., was published May 27, 2015, in the journal Science Translational Medicine.

Related Links:


Gold Supplier
STI Real-Time PCR Test
Neisseria Gonorrhoeae/Chlamydia Trachomatis/U.urealyticum Real-Time PCR Kit
Auto Immunochemistry System
Automated Chemistry Analyzer
TC-Matrix 600

Print article


Clinical Chem.

view channel
Image: Electrochemical cells etched by laser on wooden tongue depressor measure glucose and nitrite in saliva (Photo courtesy of Analytical Chemistry)

Biosensor-Fabricated Wooden Tongue Depressor Measures Glucose and Nitrite in Saliva

Physicians often use tongue depressors to examine a patient's mouth and throat. However, it is hard to imagine that this simple wooden tool could actively assess a patient's health. This idea has led to... Read more


view channel
Image: The Atellica HEMA 570 and 580 hematology analyzers remove workflow barriers (Photo courtesy of Siemens)

Next-Gen Hematology Analyzers Eliminate Workflow Roadblocks and Achieve Fast Throughput

Hematology testing is a critical aspect of patient care, utilized to establish a patient's health baseline, track treatment progress, or guide timely modifications to care. However, increasing constraints... Read more


view channel
Image: Newly observed anti-FSP antibodies have also been found to predict immune-related adverse events (Photo courtesy of Calviri)

First Blood-Based Biomarkers Test to Predict Treatment Response in Cancer Patients

Every year worldwide, lung cancer afflicts over two million individuals and almost the same number of people succumb to the disease. This malignancy leads the charts in cancer-related mortalities, with... Read more


view channel
Image: The rapid MTB strip test for tuberculosis can identify TB patients within two hours (Photo courtesy of Chulalongkorn University)

Rapid MTB Strip Test Detects Tuberculosis in Less Than an Hour without Special Tools

Tuberculosis (TB), a highly infectious disease, continues to pose significant challenges to public health worldwide. TB is caused by a bacterium known as "Mycobacterium tuberculosis," spreading through... Read more


view channel
Image: The UNIQO 160 (CE-IVDR) advances diagnostic analysis for autoimmune diseases (Photo courtesy of EUROIMMUN)

Novel Automated IIFT System Enables Cutting-Edge Diagnostic Analysis

A newly-launched automated indirect immunofluorescence test (IIFT) system for autoimmune disease diagnostics offers an all-in-one solution to enhance the efficiency of the complete IIFT process, comprising... Read more


view channel
Image: The Coris acquisition provides Avacta with a broad, professional-use rapid test product portfolio (Photo courtesy of Coris Bioconcept)

Avacta Expands Diagnostics Portfolio with Acquisition of Rapid Test Maker Coris Bioconcept

Avacta Group plc (London, UK), a life sciences company developing oncology drugs and diagnostics, has acquired Coris Bioconcept SRL (Gembloux, Belgium) for an upfront cash consideration of GBP 7.... Read more
Copyright © 2000-2023 Globetech Media. All rights reserved.