RT Journal Article SR Electronic T1 Enrichment and application of bacterial sialic acids containing polymers from the extracellular polymeric substances of “Candidatus Accumulibacter” JF bioRxiv FD Cold Spring Harbor Laboratory SP 2022.09.16.508216 DO 10.1101/2022.09.16.508216 A1 Sergio Tomás-Martínez A1 Le Min Chen A1 Martin Pabst A1 David G. Weissbrodt A1 Mark C.M. van Loosdrecht A1 Yuemei Lin YR 2022 UL http://biorxiv.org/content/early/2022/09/16/2022.09.16.508216.abstract AB Pseudaminic and legionaminic acids are a subgroup of nonulosonic acids (NulOs) unique to bacterial species. There is a lack of advances in the study of these NulOs due to their complex synthesis and production. Recently, it was seen that “Candidatus Accumulibacter” can produce Pse or Leg analogues as part of its extracellular polymeric substances (EPS). In order to employ a “Ca. Accumulibacter” enrichment as production platform for bacterial sialic acids, it is necessary to determine which fractions of the EPS of “Ca. Accumulibacter” contain NulOs and how to enrich and/or isolate them. We extracted the EPS from granules enriched with “Ca. Accumulibcater” and used size-exclusion chromatography to separate them into different molecular weight fractions. This separation resulted in two high molecular weight (> 5,500 kDa) fractions dominated by polysaccharides, with a NulO content up to 4 times higher than the extracted EPS. This suggests that NulOs in “Ca. Accumulibacter” are likely located in high molecular weight polysaccharides. Additionally, it was seen that the extracted EPS and the NulO-rich fractions can bind and neutralize histones. This suggest that they can serve as source for sepsis treatment drugs, although further purification needs to be evaluated.Graphical abstract HighlightsNulOs in “Ca. Accumulibacter” are likely located in high molecular weight polysaccharides.Size exclusion chromatography allows to obtain high molecular weight polysaccharide-rich fractions enriched with NulOs.EPS and the NulOs-rich fractions can serve as source for sepsis treatment drugs.Competing Interest StatementThe authors have declared no competing interest.