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Two Gram-positive, endospore-forming bacterial strains, CR-502T and CR-14b, which produce surfactant molecules are described. Phenotypic tests and phylogenetic analyses showed these strains to be members of the genus Bacillus and related to the species Bacillus atrophaeus, Bacillus mojavensis, Bacillus subtilis, Bacillus vallismortis and Bacillus amyloliquefaciens, although they differ from these species in a number of phenotypic characteristics. DNA–DNA hybridization confirmed that they show less than 20 % hybridization with the above-mentioned species and therefore represent a novel species of Bacillus. The DNA G+C content is 46·4 mol% in strain CR-502T and 46·1 mol% in strain CR-14b. The main fatty acids in strain CR-502T are 15 : 0 anteiso (32·70 %), 15 : 0 iso (29·86 %) and 16 : 0 (13·41 %). The main quinone in strain CR-502T is MK-7 (96·6 %). In the light of the polyphasic evidence gathered in this study, it is proposed that these strains be classified as a novel species of the genus Bacillus, with the name Bacillus velezensis sp. nov. The type strain (CR-502T=CECT 5686T=LMG 22478T) was isolated from a brackish water sample taken from the river Vélez at Torredelmar in Málaga, southern Spain.

Mauran is an anionic, sulfated heteropolysaccharide with a high uronic-acid content, synthesized by strain S-30 of the halophilic bacterium Halomonas maura. Under optimum environmental and nutritional conditions, it is capable of producing up to 3.8 g of mauran per liter of medium. Aqueous solutions of mauran are highly viscous and display pseudoplastic, viscoelastic and thixotropic behavior. Its viscosity is stable over a wide pH range (3-11), after freezing-thawing processes, and in the presence of sucrose, salts, surfactants and alpha-hydroxyl acids. It has a high capacity for binding lead and other cations. Its molecular mass when collected from an MY medium supplemented with 2.5% w/v salt during the stationary growth phase is 4.7x10(6) Da.

Four moderately halophilic, exopolysaccharide-producing bacterial strains isolated from soil samples collected from a saltern at Asilah (Morocco) are reported. These four strains were initially considered to belong to the genus Halomonas. Their DNA GMC contents varied between 622 and 641 mol %. DNA-DNA hybridization revealed a considerable degree of DNA-DNA similarity amongst all four strains (755-808 %). Nevertheless, similarity with the reference strains of phylogenetically close relatives was lower than 40 %. 16S rRNA gene sequences were compared with those of other species of Halomonas and other Gram-negative bacteria and they were sufficiently distinct phylogenetically from other recognized Halomonas species to warrant their designation as a novel species. The name Halomonas maura sp. nov. is therefore proposed, with strain S-31 T (l CECT 5298 T l DSM 13445 T ) as the type strain. The fatty acid composition of strain S-31 T revealed the presence of 18 :1ω7c, 16:1ω7c/2-OH i15 :0 and 16 :0 as the major components. Growth rate analysis showed that strain S-31 T had specific cationic requirements for Na M and Mg 2M .

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