free essays
Free essays

Report on the Elimination Process of an Unknown Organism



Inthe elimination process of an unknown microorganism, Tryptic SoyaAgar (TSA) in streak plate was used since it covers a wide range ofmicroorganisms that were generally susceptible for growth. In thelaboratory experiment performed, two unknown microorganism sampleswere collected to perform TSA streak plate. The main goal of theexperiment was to determine the two types of unknown microorganismsthat we have selected based on Bergey`s Manual of DeterminitiveBacteriology on the microorganism`s test on whether it can beconsidered a gram positive or a gram negative type of bacteria.

Asa form of differentiation, Bergey`smethod was usedto classify thetwo unknown bacteriabased on their structural and functional attributes by arranging theminto specific familial orders.As a procedure conducted in the experiment, gram staining wereperformed so as to determine whether the two unknowns were consideredas gram positive or gram negative bacteria. Moreover, the gramnegative bacteria obtained from gram staining procedure was furtherexamined through various biochemical procedures.

Resultsfrom the experiment showed that the unknown bacteria # 17, a and bare Staphylococcusepidermidis,whichis a gram positive bacteria,andAlcaligenesfaecalis,a gram negative bacteria, respectively. Staphylococcusepidermidisbelongsto a genus Staphylococcus.Itis a gram positive cocci belonging to phylum Firmicutes that formswhite, raised, cohesive, small colonies of bacteria with 1-2 mm indiameter. It can grow through aerobic respiration or by fermentationprocess. Meanwhile, Alcaligenesfaecalis,agram negative, rod-shaped phylum Proteobacteria belonging to genusAlcaligenes,iscommonly found in in water, soil, in the environment etc. andcommonly known as flagella stain, non-nitratereducing, oxidase positive, andcatalasepositive.


Holt,J. G. (2000). Bergey`sManual of Determinitive Bacteriology(9thed.). Philadelphia, USA: Williams &amp Wilkins.