Structural Analysis of the Water-soluble Carbohydrate from Asaia bogorensis by NMR Spectroscopy

Abstract

The water-soluble extracellular polysaccharide produced by Asaia bogorensis, an acetic acid bacterium, was investigated. It was suggested that the water-soluble polysaccharide seemed to be a fructan as only fructose was detected as a constituent sugar when it was hydrolyzed by trifluoroacetic acid. To confirm the glycosidic linkage of the fructan, 1 H NMR spectroscopy and 13 C NMR spectroscopy were carried out. From these results, Asaia fructan was identified as levan, which is a β-2,6 linked fructan, similar to the polysaccharide produced by Gluconacetobacter xylinus. This β-2,6-linked levan-type fructan was produced only when sucrose was used as a carbon source.

Structural analysis of fructans produced by acetic acid bacteria reveals a relation to hydrocolloid function

“…NMR structural analyses on levans from AAB are scarce, and were only performed for EPS from Asaia bogorensis (Kato et al, 2007) and Ga. xylinus (Tajima et al, 1998) yielding highly similar results as compared to the levans investigated in the current study. Recently, we have identified active levansucrases, which catalyze the formation of levans from sucrose, in G. frateurii TMW 2.767 and G. cerinus DSM 9533T (Jakob, Meissner, et al, 2012).…”

Acetic acid bacteria encode two levansucrase types of different ecological relationship

“…While dextransucrase (EC 2.4.1.5) is exclusively expressed by lactic acid bacteria (Lactobacillales), GH68 encoding genes are present among Gram-positive/-negative bacteria, archaea, fungi and plants (Öner et al, 2016). Diverse previous works revealed AAB from the genera Gluconobacter, Gluconacetobacter, Komagataeibacter, Asaia, Neoasaia and Kozakia as producers of active levansucrases (LS; EC 2.4.1.10) (Tajima et al, 1997;Arrieta et al, 2004;Kato et al, 2007;Jakob, 2014;Semjonovs et al, 2016).…”

Bacteria Asaia Sp. – The New Contamintion of Flavoured Mineral Waters

“…Bakterie Asaia sp. często izolowane są z zanieczyszczonych wód aromatyzowanych, a za źródło zanieczyszczenia tymi bakteriami uznaje się naturalne soki i aromaty owocowe [7,9,14,27,28].…”

“…Ponadto zmieniają one właściwości elektrostatyczne i stopień powinowactwa komórek do niepolarnych powierzchni. Ekspozycja wolnych grup funkcyjnych tych związków warunkuje wzajemne przyciąganie się komórek, co w efekcie prowadzi do tworzenia osadów, zmętnień lub kłaczków i intensyfikuje zjawisko adhezji w środowisku wodnym [9,16].…”