TraDIS-Xpress
Introduction
Unlock detailed genetic insights with TraDIS-Xpress, a powerful high-resolution whole-genome assay developed at the Quadram Institute. Available through QIB Extra, TraDIS-Xpress identifies how gene deletions and expression changes impact bacterial fitness under specific conditions, providing critical knowledge for antimicrobial discovery, microbial engineering, and pathogen control.
Background
TraDIS-Xpress (Transposon-Directed Insertion-Site Sequencing) advances traditional transposon mutagenesis methods by using outward-facing promoters, enabling the study of both gene disruption and gene expression effects at base-pair resolution. This unique approach allows researchers to investigate the impact of essential genes that cannot otherwise be assayed, offering a broader and deeper understanding of bacterial biology.
At the Quadram Institute, the TraDIS-Xpress team has developed a suite of highly saturated transposon mutant libraries across a range of organisms, made commercially available through QIB Extra. TraDIS-Xpress has already been successfully applied to identify bacterial responses to antimicrobial compounds, reveal vulnerabilities that can be exploited to prevent contamination, optimise bacterial growth conditions, and enhance the production of proteins or metabolites in host bacteria.
The key steps in the TraDIS-Xpress workflow are illustrated in the figure below.
(a) Steps in generating TraDIS-Xpress data:
Bacteria are transformed with a transposon and grown on selective nutrient agar (1). Colonies are pooled into a single mutant library (2), then grown under both control and test conditions (3). Genomic DNA is extracted (4) and sequenced using a customised protocol targeting transposon-genome junctions (5). Sequence reads are mapped to a reference genome to locate insertion sites (6), with read counts reflecting mutant abundance. Comparing conditions identifies mutations that confer fitness changes (7).
(b) Effects of transposon insertion with an outward-facing promoter:
The TraDIS-Xpress transposon (blue) encodes an antibiotic resistance marker (AbR) and an outward-transcribing promoter (black arrowhead). Insertion within a gene (red) usually causes inactivation. Insertion upstream can alter transcription, while insertion downstream can cause interference through RNA-mediated effects.
Source:
ResearchGate – Steps in the generation of data using TraDIS-XpressService
The TraDIS-Xpress service at QIB Extra begins with a detailed consultation to discuss project aims and how TraDIS-Xpress can deliver the most relevant results. Our team will collaborate with the client to design tailored experiments based on specific research or industrial needs. All experimental work is carried out at the Quadram Institute using established protocols and highly saturated mutant libraries. Following project completion, both raw and analysed data are provided, supported by a follow-up meeting to discuss findings and next steps.
For a further explanation of how TraDIS-Xpress works, please see the video below from the Quadram Institute, narrated by Professor Ian Charles OBE.
Contact Us
To learn more about how TraDIS-Xpress can support your research or to discuss your project requirements, please contact us.
You can reach the QIB Extra team via our contact us page.