Bacterial cell surface exopolysaccharides (EPS) provide a protective barrier from the external milieu and participate in host-environment interactions. Zymomonas mobilis, an ethanologenic Gram negative bacterium, is used by the industry in bio-ethanol production process, due to its extraordinary resistance to a highly ethanolic environment. We found that Z. mobilis produces a mixture of two EPSs, an [α−(1→6)-D-Manp] mannose homopolymer and a galactose containing polysaccharide: [→2)-β-D-Galf-(1→3)-β-D-Galp-(1→]n. A physicochemical study, conducted with diffusion-ordered spectroscopy (DOSY) and Dynamic Light Scattering (DLS), allowed to demonstrate that, differently from the majority of polysaccharides, ethanol is a good solvent for the galactose containing EPS, revealing that its chemical structure is specifically connected with the Zymomonas mobilis high ethanol tolerance.
Zymomonas mobilis exopolysaccharide structure and role in high ethanol tolerance / Pallach, M.; Marchetti, R.; DI LORENZO, Flaviana; Fabozzi, A.; Giraud, E.; Gully, D.; Paduano, L.; Molinaro, A.; D’Errico, G.; Silipo, A.. - In: CARBOHYDRATE POLYMERS. - ISSN 0144-8617. - 201:(2018), pp. 293-299. [10.1016/j.carbpol.2018.08.072]
Zymomonas mobilis exopolysaccharide structure and role in high ethanol tolerance
M. Pallach;R. Marchetti;Flaviana Di Lorenzo;A. Fabozzi;L. Paduano;A. Molinaro;G. D’Errico;A. Silipo
2018
Abstract
Bacterial cell surface exopolysaccharides (EPS) provide a protective barrier from the external milieu and participate in host-environment interactions. Zymomonas mobilis, an ethanologenic Gram negative bacterium, is used by the industry in bio-ethanol production process, due to its extraordinary resistance to a highly ethanolic environment. We found that Z. mobilis produces a mixture of two EPSs, an [α−(1→6)-D-Manp] mannose homopolymer and a galactose containing polysaccharide: [→2)-β-D-Galf-(1→3)-β-D-Galp-(1→]n. A physicochemical study, conducted with diffusion-ordered spectroscopy (DOSY) and Dynamic Light Scattering (DLS), allowed to demonstrate that, differently from the majority of polysaccharides, ethanol is a good solvent for the galactose containing EPS, revealing that its chemical structure is specifically connected with the Zymomonas mobilis high ethanol tolerance.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
