After experimentation, the identity of each isolate was determined using MEGA and BLAST. After thorough analysis, the identity of Isolate 1, a beach sample obtained from blood agar plate, was determined to be Fictibacillus phosphorivorans strain Ca7. This gram-positive, aerobic, and rod-shaped microorganism is commonly found in aquatic conditions and specific wetland environments, which in not surprising being that this isolate was obtained from the beach (Glaeser et al.
2013). Additionally, the lack of growth on the MacConkey (MAC) plate (Table 2) further confirms the gram-positive nature of the microorganism since MAC plates are selective for gram-negative organisms. According to a BLAST analysis, this isolate was related to a myriad of microorganisms belonging to the genus Bacillus including Bacillus funiculus and Bacillus halophilus.
Studies have indicated that Fictibacillus phosphorivorans strain Ca7 is unable to ferment glucose, lactose, sucrose, or mannitol and relies on the peptone supplied on the media plates for energy production (Glaeser et al. 2013). These findings further support the results obtained during experimentation. As seen in Tables 1 and 2, Fictibacillus phosphorivorans strain Ca7 (isolate 1) tested negative for glucose, sucrose and lactose fermentation. This was indicated by a lack of color change from red to yellow on the test tubes. Furthermore, no color change was observed on the triple sugar agar (TSI) slant test, further confirming the lack of glucose, sucrose, and lactose fermentation. Additionally, lack of growth and color change on the MSA agar plate (Table 2) confirmed that the organism does not ferment mannitol.
The exact pathogenicity of this particular microorganism remains relatively unknown. In fact, many biological aspects of Fictibacillus phosphorivorans strain Ca7 are still unidentified and unexplored being that this microorganism was discovered only a few years ago in 2013 as a novel species (Glaeser et al. 2013). The isolate did, however, result in gamma hemolysis, indicating that this microorganism is incapable of destroying red blood cells.
Given this, it can be assumed that Fictibacillus phosphorivorans strain Ca7 might have a relatively low pathogenicity. The second isolate, a backbay sample obtained from NA plate, was determined to be Bacillus megaterium strain ATCC 14581. This gram positive, aerobic, and rod-shaped microorganism can be found in a variety of diverse environments including aquatic habitats, soils, and plant environment (Scholle et al. 2003).
The lack of growth of this organism of the MAC plate confirms the gram-positive nature of this isolate since MAC agar plates are selective towards gram-negative organisms (Table 2). Studies have also indicated that B. megaterium is able to ferment glucose, sucrose, and mannitol (White 1972). Certain strains of this microorganism are also capable of lactose fermentation (White 1972). These findings are parallel with the results obtained from the experiment. As seen in Table 1, this isolate tested positive for both glucose and sucrose fermentation. Furthermore, when placed onto a MSA plate, B.
megaterium strain ATCC 14581 was able to successfully turn the phenol red in the plate yellow, further confirming its ability to ferment mannitol (Table 2). Additionally, B. megaterium resulted in gamma hemolysis and was determined to be non-pathogenic. As its name suggests, B. megaterium is composed of a relatively large shape and is perhaps one of the largest known microorganisms.
Its massive composition along with its non-pathogenic nature contributes to the organisms medicinal, biological, economic and industrial importance (Vary et al. 2007). The production of diverse enzymes and proteins is a very desirable feature of B. megaterium.
Crucial enzymes, such as penicillin amylase, further contribute to the importance of B. megaterium in the pharmaceutical field (Vary et al. 2007). Furthermore, its ability to house plasmids from other microorganism makes B. megaterium essential in understanding concepts such as plasmid transformation, cloning, and gene expression. Isolate 3, a beach sample obtained from anaerobic blood agar plate, was determined to be Staphylococcus saccharolyticus strain JCM 1768. This gram-positive cocci can only grow in anaerobic environments, thus categorized as an obligate anaerobe (Westblom 1990).
These findings were not surprising being that the sample for this particular isolate was obtained from an anaerobic grown bacteria. The gram-positive aspect of the isolate was confirmed by the lack of growth of the MAC plate (Table 2). Furthermore, S. saccharolyticus strain resulted in a beta-hemolysis, thus categorizing it as highly pathogenic (Table 2). In fact, S. saccharolyticus has been linked to causing anaerobic endocarditis and pneumonia, both of which can be fatal (Westblom 1990).
The lack of information and experience with this particular organism makes these conditions quite difficult to treat. Strong antibiotic resistance also contributes to the difficulty of treatment (Wu et al. 2009).This particular species of Staphylococci also tested positive for glucose fermentation and negative for sucrose and lactose fermentation. The glucose fermentation was also observed in the TSI agar slant test, indicated by the color change from red to yellow on the bottom of the tube. Unfortunately, being that little is known about Staphylococcus saccharolyticus strain JCM 1768, these findings could not be confirmed.