<Tr> <Td> </Td> <Td> It has been suggested that Polysaccharide encapsulated bacteria be merged into this article . (Discuss) Proposed since November 2017 . </Td> </Tr> <P> The bacterial capsule is a very large structure of many bacteria . It is a polysaccharide layer that lies outside the cell envelope, and is thus deemed part of the outer envelope of a bacterial cell . It is a well - organized layer, not easily washed off, and it can be the cause of various diseases . </P> <P> The capsule--which can be found in both gram negative and gram - positive bacteria--is different to the second lipid membrane--bacterial outer membrane, which contains lipopolysaccharides and lipoproteins and is found only in gram - negative bacteria . When the amorphous viscid secretion (that makes up the capsule) diffuses into the surrounding medium and remains as a loose undemarcated secretion, it is known as slime layer . </P> <P> It usually consists of polysaccharides, but can be composed of other materials such as polypeptide D - glutamic acid in B. anthracis, and peptidoglycan and muramic acid found in E. coli bacterial capsule . Because most capsules are so tightly packed, they are difficult to stain because most standard stains cannot adhere to the capsule . For examination under the microscope, the bacteria and their background are stained darker than the capsule, which doesn't stain . When viewed, bacterial cells as well as the surface they are on, are stained dark, while the capsule remains pale or colorless and appears as a ring, or halo, around the cell . </P>

Lps is found in the capsule of gram-negative bacteria