An heteropolysaccharide known as Biopolymer PS 87 comprises glucose, galactose, mannose, glucuronic acid and fucose. Biopolymer PS 87 is pseudoplastic, has a consistency at 20.degree. C. of at least 150 poise and a yield stress value at 20.degree. C. of at least 30 dynes/cm.sup.2. Biopolymer PS 87 is synthesized by a strain of Bacillus polymyxa or a genetically similar micro-organism and has many domestic and industrial uses as a suspending agent or thickener.