Citrate: The citrate test gave a positive result, showing a dark blue color in the tube, caused by the alkaline conditions present, which is caused by the bacteria’s ability to utilize the citric acid present in the citrate slant. The positive result confirms the presecnce of the citrase enzyme. H2S Production: The H2S test yielded a positive result, giving rise to a black precipitate created by iron and H2S combining. Proving the presence of the desulfurase enzyme. Indole: The indole test yielded a negative result, giving a yellow ring at the top of the test tube caused by lacking a reaction between Kovac’s reagent and indole, due to the fact that there is no indole present in the tube, as well as no tryptophanase enzyme. Methyl Red:
