Some of the most common diseases are infections caused by bacteria, such as Campylobacter, Salmonella, Shigella, E. coli O157:H7, Listeria, botulism, and norovirus.
A genotype is the actual genetic coding for an organism. A phenotype is the physical appearance. For example, let's say BB or Bb is the coding for black hair. BB/Bb is the genotype, and the black hair is the phenotype.
A genotype indicates the genetic state of the DNA in an organism. It is a theoretical construct describing a genetic situation that explains the observed properties (phenotype, see below) of a strain. E. coli genotypes list only genes that are defective (1). If a gene is not mentioned, then it is not known to be mutated*â . Prophages and plasmids that were present in the original K-12 strain (F, l, e14, rac) are normally listed only if absent.