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Biology subjects

Shabat, D.

Publications and source records attributed to Shabat, D..

2 recordsLinked to original sources

Chemiluminescent probes allow for the rapid identification of colibactin-producing bacteria

The pks (or clb) gene cluster, which produces the genotoxic natural product colibactin, is encoded by human gut Enterobacteriaceae, including many commensal strains of E. coli. Colibactin crosslinks DNA and is implicated in colorectal cancer development, highlighting the importance of identifying colibactin-producing gut bacteria within biological samples. In this study, we develop phenoxy-dioxetane chemiluminescent probes that selectively react with a critical colibactin biosynthetic enzyme, the serine peptidase ClbP. We show that these chemiluminescent probes have superior sensitivity, speed, and detection capabilities compared to previously reported fluorescent ClbP probes. Furthermore, we employ these chemiluminescent probes to detect pks+ E. coli directly in complex stool suspensions. These probes will enable multiple applications requiring detection of colibactin-producing bacteria, including the identification of ClbP inhibitors and the screening of clinical samples.

biochemistry↗

A chemiluminescent protease probe for rapid, sensitive, and inexpensive detection of live Mycobacterium tuberculosis

Tuberculosis (TB) is a top-ten cause of death worldwide. Successful treatment is often limited by insufficient diagnostic capabilities, especially at the point of care in low-resource settings. The ideal diagnostic must be fast, cheap, and require minimal clinical resources while providing high sensitivity, selectivity, and the ability to differentiate live from dead bacteria. We describe here the development of a Fast, Luminescent, and Affordable Sensor of Hip1 (FLASH) for the diagnosis and monitoring of drug sensitivity of Mycobacterium tuberculosis (Mtb). FLASH is a selective chemiluminescent substrate for the Mtb protease Hip1 that when processed, produces visible light that can be measured with a high signal to noise ratio using inexpensive sensors. FLASH is sensitive to fmol of recombinant Hip1 enzyme in vitro and can detect as few as thousands of Mtb cells in culture or in human sputum samples within minutes. The probe is highly selective for Mtb compared to other non-tuberculous mycobacteria and can distinguish live from dead cells. Importantly, FLASH can be used to measure antibiotic killing of Mtb in culture with greatly accelerated timelines compared to traditional protocols. Overall, FLASH has the potential to enhance both TB diagnostics and drug resistance monitoring in resource-limited settings. One Sentence SummaryA luminescent probe enables sensitive detection of Mycobacterium tuberculosis for diagnostics, treatment monitoring, and drug susceptibility testing.

microbiology↗