A team from Shanghai Jiao Tong University reports FAST in ACS Nano 2023: “Fluorescence-Activating and Absorption-Shifting Nanoprobes for Anaerobic Tracking of Gut Microbiota”.  In 2022, Zhenping Cao & al. already disclosed FAST in living bacterial probes for mice microbiota imaging.  Now they implement FAST in outer membrane vesicles (OMVs).

Imaging microbiota vesicles pathways with FAST – © 2023 ACS

OMVs are crucial for bacterial intercellular communication and the crosstalk between the gut microbiota and its host. Methods capable of visualizing gut microbiota derived OMVs would be of great significance but have been rarely reported. Here, nanoprobes carrying a [FAST] tag are prepared by combining genetic engineering and antibiotic-boosted vesicle formation and release. Benefiting from their (…) molecular oxygen-independent emission, the resulting nanovesicles can be applied as endogenous fluorescence probes to anaerobically track gut microbiota associated OMVs. These nanoprobes show flexibility in on-demand fluorescence turn-on/off and reversibly switchable emission bands for intelligent and dual-color imaging. (…) the behaviors of microbiota OMVs to not only inhibit specific pathogenic strains through membrane fusion but also repair the intestinal barrier via entering intestinal epithelia and promoting the expressions of tight junctions are tracked and identified in the gut. Based on these discoveries, OMVs are disclosed to be able to remit inflammation in a murine model of colitis following transplantation to the intestine by oral delivery. This work provides an approach to visualize the dynamics of the gut microbiota and disclose potential targets for disease intervention.

Zhenping Cao from Shanghai Jiao Tong University in ACS Nano 2023

Terry Papoutsakis of University of Delaware initially disclosed the potential of FAST for fluorescence labeling in anaerobic bacteria.  A lasting challenge for scientists since the invention of fluorescent proteins, indeed!  Since then, FAST has successfully equipped, e.g.Clostridium acetobutylicumEubacterium limosumC. saccharoperbutylacetonicumAcetobacterium woodii, E. coli, L. monocytogenes.  More recently, anaerobic protozoa, i.e., Giardia intestinalis, joined The Twinkle Factory family.  And eventually archaea, i.e., Methanococcus maripaludis & Methanosarcina acetivorans.

The Twinkle Factory offers commercial fluorogens for FAST and splitFAST.  tfFox-NP, a bright non-permeant fluorogen, and tfDarth, a “dark” chromophore, have recently completed the product range.  For a distributor in China, contact Xianghua Wang of ZhengZhou Maxcare Biotechnology or +86 181 3737 7698.

More reading to introduce FAST nanoprobes in gut microbiota

  • Mater. Today Bio 2022 – Encoding with a fluorescence-activating and absorption-shifting tag generates living bacterial probes for mammalian microbiota imaging  Shanghai Jiao Tong University