• Media type: E-Article
  • Title: Comparison and Optimization of Quantification Methods for Shigella flexneri Serotype 6 O-antigen Containing Galacturonic Acid and Methyl-Pentose
  • Contributor: Raso, Maria Michelina; Vassallo, Oscar; Micoli, Francesca; Giannelli, Carlo
  • Published: MDPI AG, 2021
  • Published in: International Journal of Molecular Sciences, 22 (2021) 22, Seite 12160
  • Language: English
  • DOI: 10.3390/ijms222212160
  • ISSN: 1422-0067
  • Keywords: Inorganic Chemistry ; Organic Chemistry ; Physical and Theoretical Chemistry ; Computer Science Applications ; Spectroscopy ; Molecular Biology ; General Medicine ; Catalysis
  • Origination:
  • Footnote:
  • Description: <jats:p>Shigella is a leading diarrheal cause of morbidity and mortality worldwide, especially in low- and middle-income countries and in children under five years of age. Increasing levels of antimicrobial resistance make vaccine development an even higher global health priority. S. flexneri serotype 6 is one of the targets of many multicomponent vaccines in development to ensure broad protection against Shigella. The O-antigen (OAg) is a key active ingredient and its content is a critical quality attribute for vaccine release in order to monitor their stability and to ensure appropriate immune response. Here, the optimization of two methods to quantify S. flexneri 6 OAg is reported together with the characterization of their performances. The optimized Dische colorimetric method allows a tenfold increment of the sensitivity with respect to the original method and is useful for fast analysis detecting selectively methyl-pentoses, as rhamnose in S. flexneri 6 OAg. Also, a more specific HPAEC-PAD method was developed, detecting the dimer galacturonic acid-galactosamine (GalA-GalN) coming from S. flexneri 6 OAg acid hydrolysis. These methods will facilitate characterization of S. flexneri 6 OAg based vaccines. The colorimetric method can be used for quantification of other polysaccharide containing methyl-pentoses, and the HPAEC-PAD could be extended to other polysaccharides containing uronic acids.</jats:p>
  • Access State: Open Access