title: Exopolysaccharides produced by the recently described halophilic bacteria Halomonas ventosae and Halomonas anticariensis.
abstract: We studied exopolysaccharides (EPSs) produced by Halomonas ventosae and Halomonas anticariensis, two novel species of halophilic bacteria. Under optimum environmental and nutritional conditions, H. ventosae strains Al12(T) and Al16 excreted 28.35 mg and 28.95 mg of EPS per 100 ml of culture medium (34.55 and 38.6 mg of EPS per gram of dry cell weight) respectively. The molecular masses of the polymers were about 50 kDa and their main components were glucose, mannose and galactose. They had high protein fractions and showed emulsifying activity on several hydrophobic substrates. Under optimum environmental and nutritional conditions, H. anticariensis strains FP35(T) and FP36 excreted about 29.65 and 49.95 mg of EPS per 100 ml of culture medium (43.6 and 50.95 mg of EPS per gram of dry cell weight) respectively. The molecular masses of the polymers were about 20 and 46 kDa respectively and were composed mainly of glucose, mannose and galacturonic acid. All EPSs produced solutions of low viscosity and pseudoplastic behaviour. They also had a high capacity for binding cations and incorporated considerable quantities of sulphates, which is highly unusual in bacterial polysaccharides. All strains assayed formed biofilms both in polystyrene wells and borosilicate test tubes.
authors.affiliation: Microbial Exopolysaccharide Research Group, Department of Microbiology, Faculty of Pharmacy, Campus Universitario de Cartuja, University of Granada, 18071 Granada, Spain.
authors.forename: Juan Antonio
authors.initials: JA
authors.lastname: Mata
authors.forename: Victoria
authors.initials: V
authors.lastname: Béjar
authors.forename: Inmaculada
authors.initials: I
authors.lastname: Llamas
authors.forename: Soledad
authors.initials: S
authors.lastname: Arias
authors.forename: Philippe
authors.initials: P
authors.lastname: Bressollier
authors.forename: Richard
authors.initials: R
authors.lastname: Tallon
authors.forename: María C
authors.initials: MC
authors.lastname: Urdaci
authors.forename: Emilia
authors.initials: E
authors.lastname: Quesada
mesh_terms: D018441:Biofilms / Q000254:growth & development; D003470:Culture Media / Q000737:chemistry; D004591:Electrophoresis, Polyacrylamide Gel; D045703:Emulsifying Agents / Q000737:chemistry; D020632:Halomonas / Q000254:growth & development / Q000378:metabolism* / Q000648:ultrastructure; D019216:Metals, Heavy / Q000378:metabolism / Q000493:pharmacokinetics; D046529:Microscopy, Electron, Transmission; D008970:Molecular Weight; D011135:Polysaccharides, Bacterial / Q000096:biosynthesis* / Q000737:chemistry; D013045:Species Specificity; D014783:Viscosity
chemical_list: D003470:Culture Media; D045703:Emulsifying Agents; D019216:Metals, Heavy; D011135:Polysaccharides, Bacterial