Hat characteristics are used by microbiologists to separate various kinds of bacteria?

It depends on how the bacteria differ. If they have different colony morphology, the streak plate method may be used. If the bacteria have different nutritional requirements, culture the bacteria in two tubes of nutrient broth, one which has the appropriate nutrients for each strain of bacteria. If one bacterium is an obligate aerobe and the other is an obligate anaerobe, grow one culture in air and the other in an anaerobic jar.