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.
Campylobacter (meaning curved bacteria) is a genus of Gram-negative, microaerophilic, oxidase-positive, nonfermentative bacteria.Campylobacter species are typically spiral-shaped and able to move via unipolar or bipolar flagella.Most Campylobacter species are pathogenic and can infect humans and other animals.t least a dozen species of Campylobacter have been implicated in human disease, with C. jejuni and C. coli the most common. C. jejuni is now recognized as one of the main causes of bacterial foodborne disease in many developed countries.