A strategy for the covalent localization of bacteria mediated by in situ chemical reactions. With a simple one-step amidite ester reaction, the primary amino group on the bacterial surface can be converted to free thiols under cytocompatibility conditions. Surface thiolation is suitable to modifying different strains, and the amount of thiols introduced by each bacterium can be easily adjusted by different feed ratios. These chemically reactive bacteria are able to spontaneously bind to the mucus layer by catalyst-free thiol-disulfide exchange between mucin-associated disulfides and newly transformed thiols on the bacterial surface and exhibit sulf-level-dependent attachment.

Reference Documentation：https://doi.org/10.1038/s41467-022-35579-6