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HE, B.

Publications and source records attributed to HE, B..

2 recordsLinked to original sources

Elucidating the Diversity and Potential Function of Ribosomally Synthesized and Post-translationally Modified Peptides in the Human Microbiome

The human microbiome holds tremendous potential for generating specialized peptides, specifically ribosomally synthesized and post-translationally modified peptides (RiPPs), significantly affecting human health by mediating interactions with other microbes and the human host. However, the capacity of our microbiome to produce these peptides and their links with human health are poorly understood. This study systematically analyzes 306,481 human microbiota-associated genomes, uncovering a broad array of yet-to-be-discovered RiPPs. These RiPPs are distributed across various body sites but show a specific enrichment in the gut and oral microbiome. Big data omics analysis reveals that numerous RiPP families are inversely related to various diseases, suggesting their potential protective effects on health. For a proof of principle study, guided by biosynthetic prediction, nine autoinducing peptides (AIPs) were chemically synthesized for in vitro and ex vivo assay. Our findings revealed that five AIPs effectively inhibited the biofilm formation of disease-associated pathogens, with one demonstrating significant anti-inflammatory capabilities. Furthermore, when ex vivo testing gut bacteria from mice with inflammatory bowel disease, we observed that two AIPs could regulate the microbial community and reduce harmful species. These findings highlight the vast potential of human microbial RiPPs in regulating microbial communities and maintaining human health, emphasizing their potential for therapeutic development.

microbiology↗

A cationic motif in Engrailed-2 homeoprotein controls its internalization via selective cell-surface glycosaminoglycans interactions

Engrailed-2 (En2) is a transcription factor that possesses as most homeoproteins the unique and intriguing property to transfer from cell to cell through unconventional pathways. The internalization mechanism of this cationic protein is far from being fully understood and is proposed to require an initial interaction with cell-surface glycosaminoglycans (GAGs). To decipher the role of GAGs in the recognition of En2 at the cell surface, we have quantified the internalization of the homeodomain region in cell lines that differ in their content in cell-surface GAGs. The binding specificity to GAGs and the influence of this interaction on the structure and dynamics of En2 was also investigated at the amino acid level. Our results show that a high-affinity GAG-binding hexadecapeptide (RKPKKKNPNKEDKRPR) located upstream of the homeodomain controls internalization efficiency of En2 through selective interactions with highly-sulfated GAGs of heparan sulfate type. Our data underline the functional importance of the intrinsically disordered basic region that precedes the prominent internalization domain in En2, and demonstrate the critical role of GAGs as an entry gate for En2, finely tuning its capacity to internalize into cells.

biochemistry↗