Question: how many chromosomes does salmonella have?
Answer: All have a single chromosome, normally 4.3–5.0 Mb in size [1, 3,4,5,6,7–8]. Different strains may also harbor extrachromosomal DNA in the form of plasmids. Plasmids often carry genes associated with virulence or antibiotic resistance and can be considered to be a rapidly evolving gene pool.