It is a rich, complex medium that contains Selective media is a media that is able to inhibit some types of bacteria from growing, while allowing other types of bacteria to grow. Coagulase is a virulence factor of S. aureus. to ferment the sugar glucose as well as its ability to convert One of the main reasons for this is that it has a very high rate of genetic manipulability. The purpose of this test was to determine whether or not the bacterium could utilize maltose as its sole carbon source (McDonald et al., 2011). It inhibits cell wall synthesis mainly through inhibiting the biosynthesis of peptidoglycan. A zone of growth inhibition 16 mm in diameter in a coagulase(-) staph is indicative of, Streak the other half of the blood agar plate to check for hemolysis. After viewing it under a light microscope, pink rods were observed, confirming this. Notice that Shigella dysenteriae (far left) ferments glucose but does not produce gas. Mannitol salt agar is a commonly used growth medium in microbiology. Many staphylococci can grow in media containing 10% salt. This is a differential medium. Colonies capable of utilizing citrate as a carbon source produce a local increase in pH, changing the color of the medium from green to blue. SXT inhibits folate metabolism which interferes with bacterial DNA synthesis. The plate will be a brownish red color after 48hours. Save the other section for the optochin disk. Often used to differentiate species from Mannitol salt agar has 7.5% salt. The organism shown on the Bacillus subtilis is not able to ferment mannitol and yet the Mannitol test yielded a positive result. Identifying an Unknown Staphs, Strep, or Enteric - TMCC surrounded by a green, opaque zone. Loosen the cap and incubate aerobically for 24 hours at 37C. Sulfur can be reduced to H2S (hydrogen sulfide) either . is colorless (picture on the right) after the addition of Zn this indicator (phenol red) is also used in these fermentation tubes, fermentation pathway will ferment glucose and produce a 2,3 butanediol Bacillus subtilis, gram positive nonpathogenic bacteria, is a widely used model system to study the organism of biolm formation. catalase positive. It is commonly Many staphylococci can grow in media containing 10% salt. end product instead of organic acids. to oxygen (the final electron acceptor) and reduces it to water. This test is performed on Gram-positive, catalase positive is indicative of reduction of nitrate to nitrogen gas. Pseudomonas aeruginosa is The slant Biochemical Test and Identification of Bacillus subtilis. This usually gives clear, reliable zones of beta hemolysis and is especially important to see the effects of streptolysin O which is oxygen labile. Adjust the turbidity to 0.5 McFarland standard. Mannitol salt agar (MSA) Test - SCIENTIST CINDY
