Summary Of Casein Unknown # 7

Unable to read the Gram Stain at first it was later confirmed that Unknown #7 was a gram negative bacteria. When introduced to Starch Unknown #7 produced no zone of clearing showing that it did not contain the enzyme amylase. When introduced to the Lipid Unknown #7 did produce a zone of clearing indicating that it did contain the enzyme lipase. When introduced to Casein Unknown #7 produced no zone of clearing indicating that it did not contain the enzyme protease. When streaked onto the Gelatin, it remained solid after being incubated for a week. When exposed to various mediums, Unknown #7 conveyed various results. Streaking on Mannitol Salt produced a yellow color indicating that the organism was a fermenter. Contrastingly streaking on to
the McConkey agar produced a yellow color change, a pink color change with the Eosin Methylene Blue agar and no visible colonies grown on the Phenyl ethyl Alcohol agar all relating to negative results and confirming that Unknown #7 was not a fermenter. When streaked onto the Blood Unknown #7 showed no change in the state of the agar correlating to the fact that there was no lysis of red blood cells.
Glucose exposure resulted in a yellow color change proving that Unknown #7 fermented glucose and produced an acid but when exposed to Sucrose Unknown #7 produced a red color change indicating that it was a non-fermented of sucrose which was reflected with an alkaline bi-product. The Enterotubes showed that Unknown #7 was an "enteric" bacterium with a score of "46141" Lysine, Adonitol, Lactose, Dulcitol/Phenylalanine, and Harnstoff/Uree were all negative, while Ornithine, Arabinose, and Sorbitol were proven to be positive. The IMViC test identifies members of Enterobacteriaceae and included Indole that tested negative, Methyl Red which produced a red color change showing that Unknown #7 could ferment glucose to acidic ends, Vogves Proskaer which tested negative because Unknown #7 failed to convert those acidic bi-products back to neutral ends, and Citrate which tested positive with a blue color change and growth on the medium because Unknown #7 was able utilize citrate. The Nitrate Reduction test displayed Incomplete Reduction with a red color change when Solution A and B were added meaning that it could only reduce NO3- to NO2-
. When exposed to Catalase Unknown #7 produced bubbles which proved that it contained catalase and could reduce free radicals such as 2H2O2 (hydrogen peroxide) to H2O (water) and O2 (oxygen). When tested for Oxidase Unknown #7 produced a purple color change which would prove that it contained cytochrome oxidase and could catalyze the oxidation of a reduced cytochrome by molecular oxygen, however knowing that Unknown #7 was an enteric bacteria and should have tested negative, the reliability of the reagent used is called into question. Turbidity was used to determine which temperature and pH Unknown #7 produced the most growth in. The organism grew best in a Temperature ranging from 20˚C to 45˚C making it a mesophile. Additionally it also presented the most growth in a pH of 7 making it a neutrophile. When testing O2 Intolerance Unknown #7 not only grew at the top of the medium but all throughout it showing that it does not utilize O2 and is no harmed by it, termed as Aerotolerant.
These results lead me to identify Unknown #7 as Salmonella.