Streptococcus, w.m. Microscope Slide

bacteria in general can be divided into gram-negative and gram-positive bacteria depending on their cell wall their peptidoglycan makeup gram-positive implies a thick peptidoglycan layer and they stain a purple color now there are two main species of gram positive cocci that causes human infections these are streptococci and staphylococci they are differentiated by two main criteria firstly their ability or inability to produce the enzyme catalase streptococcal species are catalase negative Staphylococcus species are catalase positive which allowed them to convert hydrogen peroxide to water and oxygen gas hence on a slide or tube bubbles are formed the second criteria to differentiate Staphylococcus to streptococcus is based on microscopic appearance Staphylococcus species are usually in clusters whereas streptococcus species are arranged in pairs or chains streptococcal infections rema