Amoxicillin is an antibiotic medication belonging to the aminopenicillin class of the penicillin family. The drug is used to treat bacterial infections such as middle ear infection, strep throat, pneumonia, skin infections, odontogenic infections, and urinary tract infections. It is taken by mouth, or less commonly by injection.
A flagellum is a hairlike appendage that protrudes from certain plant and animal sperm cells, and from a wide range of microorganisms to provide motility. Many protists with flagella are known as flagellates.
Ureases, functionally, belong to the superfamily of amidohydrolases and phosphotriesterases. Ureases are found in numerous bacteria, fungi, algae, plants, and some invertebrates, as well as in soils, as a soil enzyme. They are nickel-containing metalloenzymes of high molecular weight.
Helicobacter pylori, previously known as Campylobacter pylori, is a gram-negative, microaerophilic, spiral (helical) bacterium usually found in the stomach. Its helical shape is thought to have evolved in order to penetrate the mucoid lining of the stomach and thereby establish infection. The bacterium was first identified in 1982 by the Australian doctors Barry Marshall and Robin Warren. H. pylori has been associated with cancer of the mucosa-associated lymphoid tissue in the stomach, esophagus, colon, rectum, or tissues around the eye, and of lymphoid tissue in the stomach.
Helicobacter is a genus of Gram-negative bacteria possessing a characteristic helical shape. They were initially considered to be members of the genus Campylobacter, but in 1989, Goodwin et al. published sufficient reasons to justify the new genus name Helicobacter. The genus Helicobacter contains about 35 species.
Secretion is the movement of material from one point to another, such as a secreted chemical substance from a cell or gland. In contrast, excretion is the removal of certain substances or waste products from a cell or organism. The classical mechanism of cell secretion is via secretory portals at the plasma membrane called porosomes. Porosomes are permanent cup-shaped lipoprotein structures embedded in the cell membrane, where secretory vesicles transiently dock and fuse to release intra-vesicular contents from the cell.
Limosilactobacillus reuteri is a lactic acid bacterium found in a variety of natural environments, including the gastrointestinal tract of humans and other animals. It does not appear to be pathogenic and may have health effects.
Bacteria are ubiquitous, mostly free-living organisms often consisting of one biological cell. They constitute a large domain of prokaryotic microorganisms. Typically a few micrometres in length, bacteria were among the first life forms to appear on Earth, and are present in most of its habitats. Bacteria inhabit soil, water, acidic hot springs, radioactive waste, and the deep biosphere of Earth's crust. Bacteria play a vital role in many stages of the nutrient cycle by recycling nutrients and the fixation of nitrogen from the atmosphere. The nutrient cycle includes the decomposition of dead bodies; bacteria are responsible for the putrefaction stage in this process. In the biological communities surrounding hydrothermal vents and cold seeps, extremophile bacteria provide the nutrients needed to sustain life by converting dissolved compounds, such as hydrogen sulphide and methane, to energy. Bacteria also live in symbiotic and parasitic relationships with plants and animals. Most bacteria have not been characterised and there are many species that cannot be grown in the laboratory. The study of bacteria is known as bacteriology, a branch of microbiology.
Cancer bacteria are bacteria infectious organisms that are known or suspected to cause cancer. While cancer-associated bacteria have long been considered to be opportunistic, there is some evidence that bacteria may be directly carcinogenic. The strongest evidence to date involves the bacterium H. pylori and its role in gastric cancer.
Pathogenic bacteria are bacteria that can cause disease. This article focuses on the bacteria that are pathogenic to humans. Most species of bacteria are harmless and are often beneficial but others can cause infectious diseases. The number of these pathogenic species in humans is estimated to be fewer than a hundred. By contrast, several thousand species are part of the gut flora present in the digestive tract.
Estimates place the worldwide risk of cancers from infectious causes at 16.1%. Viral infections are risk factors for cervical cancer, 80% of liver cancers, and 15–20% of the other cancers. This proportion varies in different regions of the world from a high of 32.7% in Sub-Saharan Africa to 3.3% in Australia and New Zealand.
Helicobacter pullorum is a bacterium in the Helicobacteraceae family, Campylobacterales order. It was isolated from the liver, duodenum, and caecum of broiler and layer chickens, and from humans with gastroenteritis. It is a nongastric urease-negative Helicobacter species colonizing the lower bowel.
Helicobacter bilis is a bacterium in the Helicobacteraceae family, Campylobacterales order. It is a fusiform bacterium with three to 14 multiple bipolar sheathed flagella and periplasmic fibers wrapped around the cell. It is resistant to cephalothin and nalidixic acid, but sensitive to metronidazole. Like Helicobacter hepaticus, it colonizes the bile, liver, and intestine of mice, and is associated with multifocal chronic hepatitis and hepatocellular tumors.
Helicobacter muridarum is a bacterium in the Helicobacteraceae family, Campylobacterales order. It is microaerophilic and helical and was first isolated from the intestinal mucosa of rodents, hence its name. It is characterised by the presence of 9 to 11 periplasmic fibers which appear as concentric helical ridges on the surface of each cell. The cells are motile and have bipolar tufts of 10 to 14 sheathed flagella. These bacteria are nutritionally fastidious and physiologically similar to other Helicobacter species and Wolinella succinogenes, but can be differentiated from these organisms by their unique cellular ultrastructure. ST1T is its type strain.
Helicobacter felis is a bacterial species in the Helicobacteraceae family, Campylobacterales order, Helicobacter genus. This bacterium is Gram-negative, microaerophilic, urease-positive, and spiral-shaped. Its type strain is CS1T. It can be pathogenic.
Helicobacter acinonychis is a bacterium in the Helicobacteraceae family, Campylobacterales order. It was first isolated from cheetahs with gastritis, so has been associated with this disease in this particular species and others of its kind. It is Gram-negative, spiral-shaped, and grows under microaerophilic conditions. The type strain is 90-119.
Helicobacter canadensis is a bacterium in the Helicobacteraceae family, Campylobacterales order, first isolated from humans with diarrhea. Its genome has been sequenced.
Helicobacter anseris is a bacterium in the Helicobacteraceae family, Campylobacterales order. It is Gram-negative, microaerophilic, spiral to curve-shaped, being first isolated from the faeces of geese.
Helicobacter brantae is a bacterium in the Helicobacteraceae family, Campylobacterales order. It is Gram-negative, microaerophilic, spiral to curve-shaped, being first isolated from the faeces of geese.
Mark Achtman FRS is Professor of Bacterial Population Genetics at Warwick Medical School, part of the University of Warwick in the UK.
