GSS platform generates genomic barcode of DNA from bacteria using single reagent set and without amplification.
PathoGenetiX received $4 million in the first close of its Series B financing round, to which investors have committed $9.5 million. The funds will be used to complete commercial development of the firm’s lead automated pathogen identification system, which is based on its Genome Sequence Scanning (GSS) platform.
The GSS technology uses high-throughput, single-molecule DNA analysis to identify and characterize potentially thousands of bacteria in complex biological samples, within a few hours. The firm claims that unlike other diagnostic approaches that require specific reagents for detection of each pathogen, the GSS platform uses a single reagent set to create genomic barcodes that can be used to detect and identify thousands of strains from hundreds of species without the need for PCR or other amplification techniques.
“The financing reflects the outstanding progress we have made to demonstrate GSS’s unique capabilities on a comprehensive range of samples including clinical, environment, and food products using commercial prototypes of the instrumentation system,” comments John J. Canepa, PathoGenetiX CEO.
“The funding will allow us to complete development of our first commercial systems, enter the rapidly growing research market for microbiome analysis, and advance the development of applications for food and product safety and clinical diagnostics.”
The core GSS technology was developed under a five-year, $50 million Department of Homeland Security contract for use in the detection of biothreat pathogens in environmental samples. The resulting large systems were designed for continuous, automated environmental monitoring.
PathoGenetiX has expanded its development to the production of a compact benchtop instrument that can be used for rapid bacterial/strain-typing for clinical infectious disease diagnosis and in the research and food safety sectors. The company claims the system could potentially be used to help select appropriate antibiotic therapy, streamline clinical trials, and facilitate research on microbial populations. Commercial launch of a system for the research market is projected for 2012.
The GSS system first extracts genomic DNA from a biological sample and cuts it into large fragments that are labeled with a fluorescent tag that recognizes a frequently occurring 6–8 base-pair sequence. Linearized DNA fragments of about 100–300 kilobases then flow through a microfluidic chip, past a detection system, where the fragment length and spatial pattern of tags along each DNA fragment is recorded.
This tag pattern on each fragment effectively represents a genomic barcode that can be compared to patterns in a database for identifying the bacteria from which the DNA fragment was derived. Templates in the database can be generated from known sequence or by measurement in the system, PathoGenetiX adds.
The firm claims proof-of-concept studies have demonstrated the ability of the GSS technology to identify 300 bacterial organisms representing strains from a wide range of both gram-negative and gram-positive bacteria in clinical samples such as blood cultures and human stool. Separate studies have shown the platform can detect and differentiate drug-resistant and drug-susceptible strains of Saphylococcus aureus (including MRSA) in clinical isolates.
