Host Cell Wall Polysaccharides Modulate Nanosynbacteria Recognition and Attachment
- 1ADA Forsyth Institute
Abstract
Ultrasmall episymbiotic bacteria grow on the surface of their obligate bacterial hosts. These episymbionts have a restricted host range and likely rely on host-derived receptor molecules to identify and associate with cognate hosts. Nanosynbacteria from the oral microbiome, like Nanosynbacter lyticus, utilize a pair of distinct type 4 pili (T4P) for host surface interactions, T4P-1 and T4P-2. In this study we identify the adhesin components of both T4P, demonstrate that these adhesins localize to the cell wall of the cognate host Actinobacterium Schaalia odontolytica, and demonstrate that each adhesin binds distinct components of the host cell wall. The adhesin from the motility driving T4P-1, termed PilX1, showed a wide range of affinities in microarray screening and bound peptidoglycan directly, but could not bind purified cell wall polysaccharides (CWPS) from host surfaces. Conversely, the adhesin from T4P-2, termed PilX2, bound host-derived CWPS and preferentially bound episymbiont-naive hosts over episymbiont-exposed hosts. Within the bacterial host we identified two CWPS biosynthesis pathways that altered adhesin binding and episymbiont susceptibility. Disruption of a rhamnose-CWPS pathway left hosts susceptible to episymbiont binding and disruption of a fucose remodeling pathway made hosts more resistant to episymbiont binding. Analyzing polysaccharide compositions revealed multiple CWPS, potentially including a rhamnose- and mannose-rich rhamnomannan. Consistent with this finding, exogenously added rhamnose and mannose were able to block binding by N. lyticus, supporting a role for these sugars in episymbiont defense. Our study reveals that Nanosynbacteria rely on the complex sugars that coat their host bacteria for recognition and attachment.
Related
- Lycium barbarum polysaccharides modulate SOCS-1 gene methylation and promote the maturation and migration of human monocyte-derived dendritic cells in vitro
- Sanghuang polysaccharides as emerging immunomodulators: linking molecular structure, immune recognition and the gut microbiota–immune axis
- Dynamic adhesion device of phage OE33PA drives Gram-positive host recognition
- Assessing Zymoseptoria tritici Candidate Effectors in the Non-Host Nicotiana benthamiana Reveals Immune Recognition and Potential Host-Independent Activities.
- In silico characterisation of lysis and host-recognition modules in Staphylococcus aureus bacteriophage genomes
BibTeX
@misc{grossman2026host,
title = {{Host Cell Wall Polysaccharides Modulate Nanosynbacteria Recognition and Attachment}},
author = {A. S. Grossman and J. G. S. Souza and L. Lei and K. Anochchenko and M. Xia and Y. Wang and J.-L. Reyre and E. C. Lowe and X. He and P. J. Moynihan and J. D. Mougous and B. Bor},
howpublished = {bioRxiv},
year = {2026},
month = oct,
doi = {10.64898/2026.10.06.756255},
url = {https://www.biorxiv.org/content/10.64898/2026.10.06.756255v1},
note = {CC BY-NC},
}
RIS
TY - UNPB
TI - Host Cell Wall Polysaccharides Modulate Nanosynbacteria Recognition and Attachment
AU - A. S. Grossman
AU - J. G. S. Souza
AU - L. Lei
AU - K. Anochchenko
AU - M. Xia
AU - Y. Wang
AU - J.-L. Reyre
AU - E. C. Lowe
AU - X. He
AU - P. J. Moynihan
AU - J. D. Mougous
AU - B. Bor
PY - 2026
DA - 2026/10/06
PB - bioRxiv
DO - 10.64898/2026.10.06.756255
UR - https://www.biorxiv.org/content/10.64898/2026.10.06.756255v1
AB - Ultrasmall episymbiotic bacteria grow on the surface of their obligate bacterial hosts. These episymbionts have a restricted host range and likely rely on host-derived receptor molecules to identify and associate with cognate hosts. Nanosynbacteria from the oral microbiome, like Nanosynbacter lyticus, utilize a pair of distinct type 4 pili (T4P) for host surface interactions, T4P-1 and T4P-2. In this study we identify the adhesin components of both T4P, demonstrate that these adhesins localize to the cell wall of the cognate host Actinobacterium Schaalia odontolytica, and demonstrate that each adhesin binds distinct components of the host cell wall. The adhesin from the motility driving T4P-1, termed PilX1, showed a wide range of affinities in microarray screening and bound peptidoglycan directly, but could not bind purified cell wall polysaccharides (CWPS) from host surfaces. Conversely, the adhesin from T4P-2, termed PilX2, bound host-derived CWPS and preferentially bound episymbiont-naive hosts over episymbiont-exposed hosts. Within the bacterial host we identified two CWPS biosynthesis pathways that altered adhesin binding and episymbiont susceptibility. Disruption of a rhamnose-CWPS pathway left hosts susceptible to episymbiont binding and disruption of a fucose remodeling pathway made hosts more resistant to episymbiont binding. Analyzing polysaccharide compositions revealed multiple CWPS, potentially including a rhamnose- and mannose-rich rhamnomannan. Consistent with this finding, exogenously added rhamnose and mannose were able to block binding by N. lyticus, supporting a role for these sugars in episymbiont defense. Our study reveals that Nanosynbacteria rely on the complex sugars that coat their host bacteria for recognition and attachment.
ER -