Isolated thunderstorms are when there are either thunderstorms present at the current time or there is a change for them to form, but they are scattered. These usually occur in the afternoon and the evening when the sun is out at its peak and heats up the atmoshpere.
For example, bacteria from the genus Salmonella are mostly facultative anaerobes, oxidase-negative, catalase-positive and gramnegative rods. Most strains are motile and ferment glucose with production of both acid and gas.
The main criterion for differentiation between Staphylococcus and Streptococcus genera is the catalase test. Staphylococci are catalase positive whereas Streptococci are Catalase negative. Catalase is an enzyme used by bacteria to induce the reaction of reduction of hydrogen peroxide into water and oxygen.