Definition of retain. transitive verb. 1a : to keep in possession or useb : to keep in one's pay or service; specifically : to employ by paying a retainerc : to keep in mind or memory : remember.
However, some gram- positive bacteria may also have capsules. Examples for gram-negative bacteria with capsules: Escherichia â¦coli, Klebsiella pneumoniae, Salmonella. Examples for gram-positive bacteria with capsules : Bacillus megaterium, Streptococcus pyogenes, Sterptococcus pneumoniae.
A bacteria, which possesses capsule is a capsulated bacteria. The purpose of capsule staining is to observe bacterial capsule by distinguishing capsular material from the bacteria cell. Principle: In capsule staining, a smear of bacteria is made at the center of a slide.