The purpose of the study by Barr et al. is to investigate an assumed symbiotic relationship between a bacteriophage and the mucus layer of a metazoan host, which may create a defense against microbes to protect the mucus layers from bacterial infection. The mucus layer has about four times more phage than bacteria, which is seen in preliminary testing, and because phage encode hypervariable proteins that may aid in adsorption to bacteria prey, the phages may work to protect the mucus layer be adhering to the surface with the hoc protein found in the capsid of the T4 bacteriophage. The study hopes to explain the importance of the co-evolution between phages and the mucus layer by presenting evidence of their symbiotic relationship, which could help to treat bacterial infections with further investigation.
There were three experiments completed to investigate the relationship between the mucus layer and the phages present. The researchers studied the phage adherence to the mucus, the phage adherence with infection, and the role of the capsid in the phage adherence. The results of the ...
Studies have shown pertactin, a 69kDa non fimbrial outer membrane protein, facilitates attachment of the bacteria to ciliated respiratory cells. Experiments conducted on humans to test the role of pertactin have shown no significant effect except with the results from Bassinet (4). Furthermore, filamentous haemagglutinin confers infection by attaching to the host cells in the lower respiratory tract. It is about 2nm wide, and 50n...
S. flexneri causes infection via bacterial penetration of the mucous membrane in the human colon. Humans are the only known reservoir to this pathogen (7). Following invasion of M cells and upon contact with the epithelial cells of the colon, S. flexneri releases Ipa proteins through a type three secretion system. Once inside the host cell, Ipa proteins activate small GTPases in the Rho family as well as c-src, a protooncogene, leading to cytoskeletal rearrangements. This alteration to the cytoskeleton allows the bacteria to be macropinocytosed by the host cell. Once inside the host, the pathogen colonizes the cytoplasm. IcsA, a bacterial surface protein, activates the host protein N-WASP and, in turn, stimulates actin assembly by host Arp 2/3. Thus, S. flexneri develops actin-based motility enabling the pathogen to become efficient at cell-to-cell spread and host cell cytoplasmic colonization. Infected cells become highly proinflammatory and secrete IL-8. IL-8 attracts neutrophils to the site of infection. The influx of neutrophils, chemokines and cytokines to the area damages the epithelial layer permeability and, in turn, advocates further S. flexneri invasion (6). Once initial invasion of S. flexneri occurs, the targeted epithelial cells require 45 minutes to 4 hours to mount an inflammatory response (8).
Disease and parasitism play a pervasive role in all life. Many of these diseases start with microparasites, which are characterized by their ability to reproduce directly within an individual host. They are also characterized by their small size, short duration of infection, and the production of an immune response in infected and recovered individuals. Microparasites which damage hosts in the course of their association are recognized as pathogens. The level of the interaction and the extent of the resultant damage depends on both the virulence of the pathogen, as well as the host defenses. If the pathogen can overcome the host defenses, the host will be damaged and may not survive. If on the other hand the host defenses overcome the pathogen, the microparasite may fail to establish itself within the host and die.
The bodies first line of defense includes the presence of physical and chemical barriers. These limit entry of microorganisms into the body. “These include: intact skin and epithelial surfaces that act as mechanical barriers, presence of normal micro flora on the skin that compete with pathogens for nutrients and inhibit pathogen growth through lactic acid production, normal flora of throat, colon, and vagina occupy receptors that prevents colonization by pathogens.” (Ogston-Tuck, 2014, p. 55). This also includes secretions which contain antibodies.
What are microorganisms? They are organisms that you have to view with a microscope. The three that I will be discussing are bacteria, viruses, and prions. Of the three, a bacterium is the only one that can be helpful to us in many situations, and they are also the most diverse organism on the earth. The structure, reproduction, and the diseases bacteria, viruses, and prion cause are all different. Let’s begin to compare these microorganisms.
One thing that must be noted is that contrary to popular belief, infectious agents such as viruses, bacteria, parasites, etc. are not desig...
Streptococcus pneumoniae is a Gram-positive and fast-growing bacteria which inhabit upper respiratory tract in humans. Moreover, it is an aerotolerant anaerobe and usually causes respiratory diseases including pneumonia, otitis media, meningitis, peritonitis, paranasal sinusitis, septic arthritis, and osteomyelitis (Todar, 2003). According to Tettelin et al., more than 3 million of children die from meningitis or pneumonia worldwide (2001). S.pneumoniae has an enzyme known as autolysin that is responsible for disintegration and disruption of epithelial cells. Furthermore, S.pneumoniae has many essential virulence factors like capsule which is made up of polysaccharides that avoids complement C3b opsonization of cells by phagocytes. Many vaccines contain different capsular antigens which were isolated from various strains (Todar, 2003). There are plenty of S.pneumoniae strains that developed resistance to most popular antibiotics like macrolides, fluoroquinolones, and penicillin since 1990 (Tettelin et al., 2001). Antibiotic resistance was developed by the gene mutation and selection processes that, as a consequence, lead to the formation of penicillin-binding proteins, etc. (Todar, 2003).
S. pneumoniae is the leading cause of pneumonia in all ages. Pneumonia due to this organism is characterized by four stages. In the first stage the lung alveoli fill up with a serous fluid which is thought to be stimulated by the cell wall of the organism. This fluid contains a lot of organisms but little inflammatory cell...
Certain structures of bacteria are indispensable for causing sepsis. All sepsis causing bacteria have S-layer and produce capsules, slime layer and biofilm (see tab. ). These structures protect the bacteria in the tissues against phagocytosis, ROS, lytic enzymes, immune complexes, etc., whereas in the bloodstream capsule and slime layer prevent triboelectric charging, attraction and fixation on the surface of erythrocytes, oxidation and killing by the oxygen released from erythrocytes [33 ].
Infection control is a central concept to every practice of health care providers. Its main objective is to prevent the transmission of infectious diseases from both patients and health personnel (Martin et al., 2010). In dental clinic, infection control is a continuous concern for its professionals. They have to contact patients routinely and be exposed to their blood, saliva, dental plaque and pus that may contain infectious pathogens. It is important for the dental professionals to treat these fluids as if they are infectious and special precautions must be taken to handle them. In this essay, I will highlight the scope of infection control practices in dental clinics and the ways through which infectious microorganisms are transmitted in the dental clinic. Also, I will talk about some infection control guidelines implemented in dental clinics and how they meet the needs of the patients. Finally, from a personal perspective, I will mention some factors that affect the implantation of infection control guidelines and procedures.
When Fleming discovered penicillin in 1928, the world exploded with advancements in medicine, but as advancements go forward, so do reactions backfire. The strains that were once thought easily curable with a few antibiotic pills are fighting back. As antibiotic-resistant bacteria are becoming more and more prevalent due to modern medicinal practices, including overuse and unnecessary intake, factors exist which can contribute to halting this increase. Phage therapy should be implemented into Western healthcare as a replacement or safety net for antibiotics because such techniques have the potential to diminish antibiotic-resistance.
With that being said, there are a multitude of virulence factors associated with E. coli. Several traits have been added to this bacteria, such as genes that code for a toxin, virulent enzymes, and traits that help bacteria avoid phagocytosis, all of which began from the transfer of genes to nearby bacteria (1,3). The most common virulence factor is associated with processes of adding DNA from other bacteria (1). Antigens such as the O and H antigens, which are found in the cell membrane and flagella, lead to different strains of E. coli (1). In addition, E. coli have fimbria which are hair like structures that enable them to attach to the intestine and eventually form a biofilm which then begins to multiply (3). Without fimbria, this attachment
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.
Gonorrhea is a bacterium that can multiply and grow in mucus membranes in the body very qu...
Microbes are major key components in both are homes and industrial food preparation. There are number of lactic acid which is a form of bacteria which is a large group of beneficial bacteria used in certain foods while they are getting prepared such as yogurt, cheese, sour cream, butter milk and other type of fermented milk products. Things such as vinegars are produced by bacterial acetic acid fermentation. Yeast is also major use in the making of beer and wine and also for the leaving of breads. This also involves fermentations to convert corn and other vegetable carbohydrates to also make beer, wine or gasohol but also bacteria is the agents of are other foods. Other fermented foods will include things such as soy sauce, olives and cocoa. (Microbes and human life, 2013) Single cell proteins are known as dried cells of microbes which are used in protein supplement shacks. They are also called “novel food” and “minifood”. The production of this requires micro-organisms which then serve as the protein source and then the substrate which is biomass which they grow on them. There are a number of both these sources that we are able to use for the production of single cell protein (SCP). The micro-organisms used belong to the following groups of Algae, Fungi and bacteria. (Slide Share, 2012)