Catalase-positive organisms that are mixed into hydrogen peroxide will cause bubbling.
Growth from an overnight culture of the microbe is smeared on a microscope slide. A drop of 3% hydrogen peroxide is added. If copious bubbles are observed, the microbe is positive for catalase. Catalase is then added and the reaction is observed. To view the catalase test in VirtualUnknown ™ Microbiology, complete the following steps: 2. Press the Play button to watch the video. A short video clip showing microscopic observation of a catalase test for the unknown organism will play. Staphylococcus aureus (and other Staphylococcus spp.) is (unlike e.g., Streptococcus spp.) catalase positive. Colonies practically without hemolysis (Columbia agar with sheep blood, 24 hours, aerobic atmosphere, 37&#176C.).  The catalase test is done by placing a drop of hydrogen peroxide on a microscope slide. Using an applicator stick, a scientist touches the colony, and then smears a sample into the hydrogen peroxide drop. 1  If the mixture produces bubbles or froth, the organism is said to be 'catalase-positive'. Likewise, catalase has one of the highest turnover numbers of all enzymes; one catalase molecule can convert approximately 5 million molecules of hydrogen peroxide to water and oxygen each second. Procedure of catalase test. 1  Transfer a small amount of bacterial colony to a surface of clean, dry glass slide using a loop or sterile wooden stick. 2  Place a drop of 3% H 2 O 2 on to the slide and mix. 3  A positive result is the rapid evolution of oxygen (within 5-10 sec.) as evidenced by bubbling. 4  A negative result is no bubbles or only a few 5  ... Dis 1 Place a drop of 3% H 2 O 2 on to the slide and mix. 2  A positive result is the rapid evolution of oxygen (within 5-10 sec.) as evidenced by bubbling. 3  A negative result is no bubbles or only a few scattered bubbles. 4  Dispose of your slide in the biohazard glass disposal container. Thus, catalase-positive organisms that are mixed into hydrogen peroxide will cause bubbling (catalase-negative organisms will not). This test is good for distinguishing between Gram-positive cocci in chains (catalase negative) versus Gram-positive cocci in clusters (catalase positive).  Catalase is a common enzyme found in nearly all living organisms exposed to oxygen (such as bacteria, plants, and animals). It catalyzes the decomposition of hydrogen peroxide to water and oxygen. Likewise, catalase has one of the highest turnover numbers of all enzymes; one catalase molecule can convert approximately 5 million molecules of hydrogen peroxide to water and oxygen each second. Catalase is a tetramer of four polypeptide chains, each over 500 amino acids long. It contains four porphyrin heme (iron) groups that allow the enzyme to react with the hydrogen peroxide. The optimum pH for human catalase is approximately 7, and has a fairly broad maximum (the rate of reaction does not change appreciably at pHs between 6.8 and 7.5). Likewise, catalase has one of the highest turnover numbers of all enzymes; one catalase molecule can convert approximately 5 million molecules of hydrogen peroxide to water and oxygen each second. The catalase test is used to differentiate staphylococci (catalase-positive) from streptococci (catalase-negative). The enzyme, catalase, is produced by bacteria that respire using oxygen, and protects them from the toxic by-products of oxygen metabolism.  The oxidase test is used to identify bacteria that produce cytochrome c oxidase, an enzyme of the bacterial electron transport chain. (note: All bacteria that are oxidase positive are aerobic, and can use oxygen as a terminal electron acceptor in respiration. This does NOT mean that they are strict aerobes. 
http://www.vumicro.com/vumie/help/VUMICRO/Catalase_Test.htm http://www.bacteriainphotos.com/catalase_test.html https://en.wikipedia.org/wiki/Catalase http://microbeonline.com/catalase-test-principle-uses-procedure-results/ http://web.clark.edu/tkibota/240/Unknowns/Catalase.htm https://en.wikipedia.org/wiki/Catalase https://en.wikipedia.org/wiki/Catalase http://learn.chm.msu.edu/vibl/content/catalase.html http://learn.chm.msu.edu/vibl/content/oxidase.html
what is a catalase positive result