CSDB: Search results

References to other databases: GTC:G57968EI, GlycomeDB:25198
Structural formula & atomic coordinates
Sweet-II 3D model
Show glycosyltransferases

The exocellular polysaccharide S-7, a heteropolysaccharide from Azotobacter indicus variant myxogenes has been studied using methylation analysis, Smith degradation, partial acid hydrolysis, NMR spectroscopy and mass spectrometry as the principal methods. It is concluded that the repeating unit has the following structure: [structure: see text] The absolute configuration of the deoxyhexuronic acid was deduced from 1H NMR chemical shifts and is most likely D. Approximately two O-acetyl groups per repeating unit are present, one of which is presumably on the Rha residue. The structure bears great resemblance to another polysaccharide, recently studied, produced by Sphingomonas paucimobilis I-886.

structure, capsular polysaccharide, deoxyhexuronic acid, Azotobacter indicus

NCBI PubMed ID: 11383898
Journal NLM ID: 0043535
Publisher: Elsevier
Correspondence: pererik.jansson@kfcmail.hs.sll.se
Institutions: Department of Organic Chemistry, Arrhenius Laboratory, Stockholm University, Stockholm, Sweden, University College of South Stockholm, S-141 04 Huddinge, Sweden, Clinical Research Center, Analytical Unit, Karolinska Institute, Huddinge Hospital, Novum, S-141 86 Huddinge, Sweden
Methods: methylation, partial acid hydrolysis, NMR, Smith degradation

Bacterial extracellular polysaccharides are known as a cell-bound capsule, a sheath, or a slime, which is excreted into the environment. They play an important role in virulence of medical bacteria and plant-to-symbiont interaction and are used for serotyping of bacteria and production of vaccines. Some exopolysaccharides have commercial applications in industry, and claims of health benefits have been documented for an increasing number of them. Exopolysaccharides have diverse composition and structure, and some contain sugar and non-sugar components that are found in bacterial carbohydrates only. The present article provides an updated collection of the data on exopolysaccharides of various classes of gram-negative and gram-positive bacteria reported until the end of 2019. When known, biosynthesis pathways of exopolysaccharides are treated in a summary manner. References are made to structure and biosynthesis relatedness between exopolysaccharides of different bacterial taxa as well as between bacterial polysaccharides and mammalian glycosaminoglycans.

polysaccharide structure, Gram-negative bacteria, capsule, Biofilm, polysaccharide biosynthesis, gram-positive bacteria, Monosaccharide composition, Bacterial exopolysaccharide, non-sugar component

Publication DOI: 10.1016/B978-0-12-819475-1.00005-5
Publisher: Elsevier
Correspondence: marie-rose.vancalsteren@canada.ca; yknirel@gmail.com
Editors: Barchi J, Kamerling H
Institutions: N. D. Zelinsky Institute of Organic Chemistry, Russian Academy of Sciences, Moscow, Russia, Saint-Hyacinthe Research and Development Centre, Agriculture and Agri-Food Canada, Saint-Hyacinthe, QC, Canada

The genus Sphingomonas was established by Yabuuchi et al. in 1990, and has attracted much attention in recent years due to its unique ability to degrade environmental pollutants. Some Sphingomonas species can secrete high-molecular-weight extracellular polymers called sphingans, most of which are acidic heteropolysaccharides. Typical sphingans include welan gum, gellan gum, and diutan gum. Most sphingans have a typical, conserved main chain structure, and differences of side chain groups lead to different rheological characteristics, such as shear thinning, temperature or salt resistance, and viscoelasticity. In petroleum production applications, sphingans, and their structurally modified derivatives can replace partially hydrolyzed polyacrylamide (HPAM) for enhanced oil recovery (EOR) in high-temperature and high-salt reservoirs, while also being able to replace guar gum as a fracturing fluid thickener. This paper focuses on the applications of sphingans and their derivatives in EOR.

Sphingomonas, gellan, sphingan, welan, application, biopolymer, diutan, EOR

NCBI PubMed ID: 35567089
Publication DOI: 10.3390/polym14091920
Journal NLM ID: 101545357
Publisher: Basel: MDPI
Correspondence: lishuang@njtech.edu.cn
Institutions: College of Biotechnology and Pharmaceutical Engineering, Jiangpu Campus, Nanjing Tech University, Nanjing 211816, China, Research Institute of Petroleum Engineering and Technology, Shengli Oilfield Company, Sinopec, Dongying 257000, China