(2). Unknown 15 was examined after a one week incubation period, thus, it demonstrated gamma-hemolysis. Mannitol Salt Agar (MSA) was used to distinguish whether Unknown 15 belonged to the genus Enterococcus or Lactococcus. When streak plated onto the MSA medium, Unknown 15 grew on the plate and produced a yellow color change. The growth and color change (indicative of mannitol fermentation) resembled the the positive control Staphylococcus aureus. Very few microorganisms are capable of, both, growing on the halophilic medium and fermenting mannitol; thus, the genus Lactococcus was eliminated…
1.Introduction: Background/Aim. 1.1 Nature of the microorganism: Enterococcus faecalis was placed under group D streptococci because of similar lysis characters; Identified as Gram positive, non-motile, anaerobic fermentative, lactic acid bacteria; are commensal inhabitant of intestinal bacteria and opportunistic pathogens. They occur singly or in pairs or chains. 1.2 Economic importance: Enterococcus faecalis is also used as a probiotic for production of Mediterranean cheese and meat products…
Investigating Enterococcus faecalis’s structures and resistances to antibiotics Introduction Bacteria’s phenotype is commonly described as gram-negative or gram-positive from conducting a gram stain. A bacterium that is gram-negative tends to have cells composed of a thin peptidoglycan layer, and a gram stain of gram-negative bacteria are seen as red or pink through a microscope (Smith and Hussey, 2005). On the other hand, a bacterium that is gram-positive will have cells made of a thick…
Unknown Lab Report: Unknown #20 Unknown Number: #20 Bacteria identified as Enterococcus casseliflavus. Introduction: Many bacteria have existed for hundreds of millions of years that we have not yet discovered. Those bacteria can survive under the thawing layers of ice, so when it melts, they are awakened and become strongly active. These bacteria are consumed by plants and animals, whom we also consume as our daily source of food. The basis for those bacteria can lead to certain epidemics.…
on an unknown bacterium. Since numerous kinds of microorganisms cultivate in and on the human body as normal microbiota, proper identification is required. Identifying unknown bacteria is part of an important aspect in microbiology. In order to properly identify the unknown bacterium following procedures is required which can be found in Material & Methods. Moreover, Exercise 28 focuses on Streptococci and Enterococci. The genus of streptococcus is streptococci and the genus for enterococcus is…
After my gram staining I was able to comfortably eliminate all of the gram negative results. This encouraged me in knowing that I was able to execute an experiment efficiently enough to eliminate some of my choices. I was also able to eliminate all of the streptococcus bacteria because my bacteria was in clusters and not in a chain arrangement. Gram staining also helped me in eliminating the bacilli because my interpretation of the observation was that my unknown bacteria was spherical in nature…
Gram-positive cocci are an interesting group of bacteria to study. Some common species include Staphylococcus aureus, Staphylococcus epidermidis, Enterococcus faecalis, Streptococcus pyogenes, and Sarcina lutea. Gram-positive cocci have a gram positive cell wall, cocci morphology and many different styles of grouping. Some species have begun to exhibit a resistance to fluoroquinolone by the use of altering the drug binding site and the use of a membrane pump (Hooper 2002). Thanks to the…
Violet red bile agar is a selective medium used to identify lactose-fermenting coliforms. This medium is typically used to test dairy products and water. The medium contains lactose which acts as a carbohydrate source, bile salts and crystal violet that act as an inhibitory agent towards gram-positive microorganisms and neutral red is added to serve as a pH indicator, microorganisms lower the pH which results in the colonies turning red. Some of the organisms that grow on this medium are:…
There is a surplus amount of microorganisms that are out there in the world. A single swab of any surface, including the human body, will yield many different types of microorganisms. Once grown on a nutrient-rich medium, the identification of these microorganisms can be made by isolating pure colonies and performing and using various plates and broth and recording its characteristics. It is important to understand and characterize each microorganism, behavior, reaction, and appearance for…
antibiotics, known as beta-lactamases (Rice 2012). The first method,that of producing new PBPs is most common in gram-positive bacteria, such as Staphylococcus aureus, which produces PBP2a,or Enterococcus faecium, which produces PBP5 (Rice 2012). Gram-negative bacteria however favour the production of beta-lactamases (Rice 2012). These enzymes9e similar in structure to PBPs, and so are able to catalyse the hydrolisation of the beta-lactam ring, rendering the antibiotic ineffective (Andersson,…