Modulation of bacterial multicellularity via spatiotemporal polysaccharide secretion

Islam, S. T.; Vergara Alvarez, I.; Saïdi, F.; Giuseppi, A.; Vinogradov, E.; Morrone, C.; Brasseur, G.; Sharma, G.; Benarouche, A.; Bridot, J.-L.; Ravicoularamin, G.; Cagna, A.; Gauthier, C.; Singer, M.; Fierobe, H.-P.; Mignot, T.; Mauriello, E. M. F.

doi:10.1101/2020.02.20.957654

bioRxiv · 10.1101/2020.02.20.957654

Modulation of bacterial multicellularity via spatiotemporal polysaccharide secretion

Islam, S. T.·Vergara Alvarez, I.·Saïdi, F.·Giuseppi, A.·Vinogradov, E.·Morrone, C.·Brasseur, G.·Sharma, G.·Benarouche, A.·Bridot, J.-L.·Ravicoularamin, G.·Cagna, A.·Gauthier, C.·Singer, M.·Fierobe, H.-P.·Mignot, T.·Mauriello, E. M. F.

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Abstract

AO_SCPLOWBSTRACTC_SCPLOWThe development of multicellularity is a key evolutionary transition allowing for differentiation of physiological functions across a cell population that confers survival benefits; among unicellular bacteria, this can lead to complex developmental behaviours and the formation of higher-order community structures. Herein, we demonstrate that in the social {delta}-proteobacterium Myxococcus xanthus, the secretion of a novel secreted biosurfactant polysaccharide (BPS) is temporally and spatially modulated within communities, mediating swarm migration as well as the formation of multicellular swarm biofilms and fruiting bodies. BPS is a type IV pilus-inhibited acidic polymer built of randomly-acetylated {beta}-linked tetrasaccharide repeats. Both BPS and the "shared good" EPS are produced by dedicated Wzx/Wzy-dependent polysaccharide assembly pathways distinct from that responsible for spore coat assembly. To our knowledge, such pathways have never-before been explicitly shown to synthesize a biosurfactant. Together, these data reveal the central role of secreted polysaccharides in the intricate behaviours coordinating bacterial multicellularity.

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Islam, S. T., Vergara Alvarez, I., Saïdi, F., Giuseppi, A., Vinogradov, E., Morrone, C., Brasseur, G., Sharma, G., Benarouche, A., Bridot, J.-L., Ravicoularamin, G., Cagna, A., Gauthier, C., Singer, M., Fierobe, H.-P., Mignot, T., Mauriello, E. M. F.. 2020-02-20. Modulation of bacterial multicellularity via spatiotemporal polysaccharide secretion. https://doi.org/10.1101/2020.02.20.957654

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