Bacteria are microorganisms that make up a sizeable domain of prokaryotic organisms. Bacteria are exceptionally adaptable to conditions and can differ in, morphologies: ranging from cocci, bacilli, vibrio and spirochaetes, they are typically a few micrometres in size. The wide variety of shapes is determined by the cell wall and cytoskeleton composition, it is important as it can influence the bacteria’s ability to acquire nutrients, motility and attach to surfaces forming biofilms. Many bacteria exist simply as single cell organisms but can have other forms, diploids (pairs), streptococcus (chains) and staphylococcus (clusters).
Bacteria are vital in recycling nutrients, with several stages in the nutrient cycles that depend on the organisms, such as the fixation of nitrogen from the atmosphere. Bacteria require nutrients to sustain life and populate a large diversity of habitats and are found in almost every environment: soil, air, acid hot springs, fresh water, earths crust and plants. Bacteria are also found in animals making up the bodies natural flora. The majority of these bacteria render harmless by the protective effects of the body’s immune system, certain bacteria are beneficial to the host. However, some bacteria are opportunistic and pathogenic causing infectious diseases such as anthrax, listeriosis, Lyme disease, salmonellosis diphtheria and septicaemia.
Particularly problematic disease causing bacteria are Enterococcus organisms. The genus Enterococcus is composed of Gram-positive cocci that occur singly, in pairs or as short chains. They are non-sporing, faculatively anaerobic, catalase-negative bacteria, with fermentative metabolism resulting in L(+) lactic acid as the major product of glucose fermentative. The...
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...sh between species and genus. Due to this the application of molecular techniques for the rapid identification of Enterococcus species has been expanded for use in clinical microbiology laboratories. A variety of molecular procedure has been proposed for the identification of enterococci species with future improvements may be available for rapid and precise detections of enterococci directly in clinical samples. The introduction of molecular techniques has substantially improved the ability to discriminate enterococci isolates and has provided critical insights into the epidemiology of the enterococci. Genus-specific PCR primers to 16S rRNA have previously been designed and found to be useful in identifying strains of Enterococcus. PCR amplification followed by sequencing and sequence comparison of target genes has allowed differentiation of species of enterococci.
The purpose of this study is to identify an unknown bacterium from a mixed culture, by conducting different biochemical tests. Bacteria are an integral part of our ecosystem. They can be found anywhere and identifying them becomes crucial to understanding their characteristics and their effects on other living things, especially humans. Biochemical testing helps us identify the microorganism present with great accuracy. The tests used in this experiment are rudimentary but are fundamental starting points for tests used in medical labs and helps students attain a better understanding of how tests are conducted in a real lab setting. The first step in this process is to use gram-staining technique to narrow down the unknown bacteria into one of the two big domains; gram-negative and gram-positive. Once the gram type is identified, biochemical tests are conducted to narrow down the specific bacterial species. These biochemical tests are process of elimination that relies on the bacteria’s ability to breakdown certain kinds of food sources, their respiratory abilities and other biochemical conditions found in nature.
The results of the gram stain test were cocci and purple. This indicated that the unknown bacteria were gram positive. The gram stain test eliminated Escherichia coli, Klebsiella pneumonia, Salmonella enterica, and Yersinia enterocolitica as choices because these bacteria are gram negative. Next a Blood Agar plate was used because in order to do a MSA or a Catalase test there needs to be a colony of the bacteria. The result of the Blood Agar plate was nonhemolytic.
Bacteria can function and reproduce as single cells but often combine into multicellular colonies. Bacteria are also surrounded by a cell wall. Archaea differ from bacteria in their genetics and biochemistry. Their cell membranes are made with different material than bacteria.
It has an outer membrane that contains lipopolysaccharides, a periplasmic space with a peptidoglycan layer, and an inner cytoplasmic membrane. It also consists of adhesive fibres. Some strains of E. coli are piliated and are capable of accepting, as well as transferring plasmids to and from other bacteria. This enables the bacteria under stressful or bad conditions to survive. Although its structure is simple with only one chromosomal DNA and a plasmid, it can perform complicated metabolism to help maintain its cell division and cell growth.
If the oxidase test was to be negative then the bacteria would have to be S. flexnery. S. flexneri is a bacterium that causes diarrheal disease, and it’s a “facultative anaerobe belonging to the family Enterobacteriaceae” (“Shigella flexneri”, n.d). However, if the oxidase test came as positive then the bacteria would have to either P. aeruginosa or A. faecalis (“Microbiology 20 Biochemical Unknown, 2009). Then an indole test will have to be done. An indole test is to identify if the bacteria could produce the enzyme tryptophase (SIM Medium”, n.d). If the test came as positive then unknown bacteria 2 would be P. aeruginosa (“Microbiology 20 Biochemical Unknown, 2009). P. aeruginosa is a bacterium that is the number one leading infections in humans. The bacterium is Gram negative that can lead to “endocarditis, meningitis, etc. (Friedrich.M, Dec 5, 2016). In the other hand if the bacteria came as indole negative then bacteria 2 would be A faecalis. A faecalis is a Gram-negative, rod-shape bacterium with flagella, and that belongs to the family Alcaligenaceas”, and it’s an opportunistic pathogen that induces infection (“Alcaligenes faecalis”, n.d). All in all, skills were practices to determine two unknown
Bacteria play a large role in our health, the environment, and most aspects of life. They can be used in beneficial ways, such as decomposing wastes, enhancing fertilizer for crops, and breaking down of substances that our bodies cannot. However, many bacteria can also be very harmful by causing disease. Understanding how to identify bacteria has numerous applications and is incredibly important for anyone planning to enter the medical field or begin a career in research. Having the background knowledge of identifying an unknown bacteria may one day aid healthcare professionals diagnose their patient with a particular bacterial infection or help researchers determine various clinical, agricultural, and numerous other uses for bacteria.
The body contains bacteria both inner and outer. The human body and some of there bacteria that the body contains is mutualistic. Mutualism is where both bacteria and host, human body, benefit from each other, and need one another in order to function. This bacteria is known as normal microbiota, harmless bacteria the body has. Yet, there are circumstances where these bacteria can cause harm if it enters through a wound into unknown tissue. However, biologists have several reasons why they want to learn more about these bacteria. The first is to understand the various bacteria in the body to further know how possible infections can be caused. Second is to know about the native microbes on any one-body part, allowing physicians to know what to test for. Third find out what happens when bacteria is present in locations where they are not normally at. Lastly, to inform people about the important role these bacteria have to help the human bodies immune system, and protection against other microorganisms. This experiment deals with isolating bacteria from the throat, skin and rectum is optional. This bacteria will be grown in different agar plats. Different agar plates are used to grow specific
Enterococcus faecalis is a genus of gram positive cocci and form short chains or are arranged in pairs. They are nonmotile, facultative anaerobic organisms and can survive in harsh conditions in nature. There are over 15 species of the Enterococcus genus but about 90% of clinical isolates are E. faecalis. E. faecalis is a nosocomial pathogen because it is commonly found in the hospital environment and can cause life-threatening infections in humans. It is a bacterium that normally inhabits the intestinal tract in humans and animals but when found in other body locations it can cause serious infections. The most common sites for E. faecalis infections are the heart, bloodstream, urinary tract, and skin wounds. Due to vancomycin-resistant Enterococci, many antibiotics have been shown ineffective in the treatment. In this paper, I will describe the ecology and pathology of E. faecalis; the antibacterial resistance; treatment; and, what you can do to prevent Enterococcus infection.
Multiplication of attached organisms leads to confluent growth and biofilm formation. Adherent bacteria synthesise extracellular polymers.
Bacterial cells, like plant cells, are surrounded by a cell wall. However, bacterial cell walls are made up of polysaccharide chains linked to amino acids, while plant cell walls are made up of cellulose, which contains no amino acids. Many bacteria secrete a slimy capsule around the outside of the cell wall. The capsule provides additional protection for the cell. Many of the bacteria that cause diseases in animals are surrounded by a capsule. The capsule prevents the white blood cells and antibodies from destroying the invading bacterium. Inside the capsule and the cell wall is the cell membrane. In aerobic bacteria, the reactions of cellular respiration take place on fingerlike infoldings of the cell membrane. Ribosomes are scattered throughout the cytoplasm, and the DNA is generally found in the center of the cell. Many bacilli and spirilla have flagella, which are used for locomotion in water. A few types of bacteria that lack flagella move by gliding on a surface. However, the mechanism of this gliding motion is unknown. Most bacteria are aerobic, they require free oxygen to carry on cellular respiration. Some bacteria, called facultatibe anaerobes can live in either the presence or absence of free oxygen. They obtain energy either by aerobic respiration when oxygen is present or by fermentation when oxygen is absent. Still other bacteria cannot live in the presence of oxygen. These are called obligate anaerobes. Such bacteria obtain energy only fermentation. Through fermentation, different groups of bacteria produce a wide variety of organic compounds. Besides ethyl alcohol and lactic acid, bacterial fermentation can produce acetic acid, acetone, butyl alcohol, glycol, butyric acid, propionic acid, and methane, the main component of natural gas. Most bacteria are heterotrophic bacteria are either saprophytes or parasites. Saprophytes feed on the remains of dead plants and animals, and ordinarily do not cause disease. They release digestive enzymes onto the organic matter. The enzymes breakdown the large food molecules into smaller molecules, which are absorbed by the bacterial cells. Parasites live on or in living organisms, and may cause disease. A few types of bacteria are Autotrophic, they can synthesize the organic nutrients they require from inorganic substances. Autotrophic bacteria are either photosynthetic or Chemosynthetic. The photosynthetic bacteria contain chlorophyll that are different from the plant chlorophyll. In bacterial photosynthesis, hydrogen is obtained by the splitting of compounds other than water.
Prescott, Harley & Klein (1990) describe bacteria as prokaryotic cells (cells that lack a true membrane enclosed nucleus). Bacteria are both small and simple in structure; they usually are between o.5 and 5cmm yet they have many characteristic shapes and sizes. Some bacteria are circular or oval shaped, they are known as cocci bacteria. Other bacteria are rod-shaped, they are known as bacilli bacteria, and some bacteria are spiral and coil-shaped and it is know as spirilla bacteria.
Bacteria are found nearly everywhere within the body and most types are harmless or even helpful to bodily function (Novitt-Moreno). While it is important to have these bacteria in the body, pathogenic invaders can cause serious illnesses. Pathogenic bacteria work by either actually attacking a part of the victim’s body or releasing toxic waste products into the body. Bacteria are single-celled and contain all of the cellular mechanisms needed to live, grow, and reproduce (Novitt-Moreno). That means, when treating a bacterial infection, it is critical to have a highly specific antibiotic that can destroy the unwanted
Microbes are everywhere in the biosphere, and their presence invariably affects the environment in which they grow. The effects
Biofilms are formed by a six step process. First is a reversible process, when an organic monolayer(made of polysaccharides or glycoproteins) absorbs to the surface, altering the chemical and physical properties of the surface. This makes the surface more conditioned and increase the chance that planktonic bacteria will attach. Secondly, also a reversible step, is when the free-floating or planktonic bacteria encounter the conditioned surface, and some attachment of the bacteria may occur. The third step is when the bacteria is left attached too long, then an irreversible attachment occurs. F...
The most commonly recognized food borne infections are those caused by the bacteria Campylobacter, Salmonella, and E. coli 0157:H7, and by a group of viruses called Calicivirus, also know as the Norwalk viruses. “Thousands of types of bacteria are naturally present in our environment, but not all bacteria cause disease in humans.” (Schmutz 1)