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Actinomyces
''Actinomyces'' is a genus of the Actinomycetia class of bacteria. They all are Gram-positive and facultatively anaerobic, growing best under anaerobic conditions. ''Actinomyces'' species may form endospores, and while individual bacteria are rod-shaped, ''Actinomyces'' colonies form fungus-like branched networks of hyphae. The aspect of these colonies initially led to the incorrect assumption that the organism was a fungus and to the name ''Actinomyces'', "ray fungus" (from Greek , ray or beam, and , fungus). ''Actinomyces'' species are ubiquitous, occurring in soil and in the microbiota of animals, including the human microbiota. They are known for the important role they play in soil ecology; they produce a number of enzymes that help degrade organic plant material, lignin, and chitin. Thus, their presence is important in the formation of compost. Certain species are commensal in the skin flora, oral flora, gut flora, and vaginal flora of humans and livestock. They are also ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Human Microbiota
Human microbiota are microorganisms (bacteria, viruses, fungi and archaea) found in a specific environment. They can be found in the stomach, intestines, skin, genitals and other parts of the body. Various body parts have diverse microorganisms. Some microbes are specific to certain body parts and others are associated with many microbiomes. This article lists some of the species recognized as belonging to the human microbiome and focuses on the oral, vaginal, ovarian follicle, uterus and the male reproductive tract microbiota. Categories of bacteria The "reference" 70 kg human body is estimated to have around 39 trillion bacteria with a mass of about 0.2 kg. These can be separated into about 10,000 microbial species, about 180 of the most studied is listed below here. However, these can broadly be put into three categories: Spheres or ball-shaped (cocci bacteria) Cocci are usually round or spherical in shape. They can form clusters and are non-motile. Examples incl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Actinomycetia
Actinomycetia is a class of bacteria. Taxonomy The currently accepted taxonomy is based on the List of Prokaryotic names with Standing in Nomenclature (LPSN) and National Center for Biotechnology Information (NCBI). * Acidothermales Sen et al. 2014 * Actinomycetales Buchanan 1917 (Approved Lists 1980) * ? Bifidobacteriales Stackebrandt et al. 1997 * Catenulisporales Donadio et al. 2015 * Cryptosporangiales Nouioui et al. 2018 * Frankiales Sen et al. 2014 * Geodermatophilales Sen et al. 2014 * ? Glycomycetales Labeda 2015 * Jatrophihabitantales Salam et al. 2020 * Jiangellales Tang et al. 2015 * Kineosporiales Kämpfer 2015 * ? Micrococcales Prévot 1940 (Approved Lists 1980) * Micromonosporales Genilloud 2015 * Motilibacterales Salam et al. 2020 * Mycobacteriales Janke 1924 (Approved Lists 1980) * Nakamurellales Sen et al. 2014 * Propionibacteriales (Rainey et al. 1997) Patrick and McDowell 2015 * Pseudonocardiales Labeda and Goodfellow 2015 * Sporichthyales Noui ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gram-positive Bacteria
In bacteriology, gram-positive bacteria are bacteria that give a positive result in the Gram stain test, which is traditionally used to quickly classify bacteria into two broad categories according to their type of cell wall. The Gram stain is used by microbiologists to place bacteria into two main categories, gram-positive (+) and gram-negative (−). Gram-positive bacteria have a thick layer of peptidoglycan within the cell wall, and gram-negative bacteria have a thin layer of peptidoglycan. Gram-positive bacteria retain the crystal violet stain used in the test, resulting in a purple color when observed through an optical microscope. The thick layer of peptidoglycan in the bacterial cell wall retains the stain after it has been fixed in place by iodine. During the decolorization step, the decolorizer removes crystal violet from all other cells. Conversely, gram-negative bacteria cannot retain the violet stain after the decolorization step; alcohol used in this stage ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oral Flora
Oral microbiology is the study of the microorganisms (microbiota) of the oral cavity and their interactions between oral microorganisms or with the host. The environment present in the human mouth is suited to the growth of characteristic microorganisms found there. It provides a source of water and nutrients, as well as a moderate temperature. Resident microbes of the mouth adhere to the teeth and gums to resist mechanical flushing from the mouth to stomach where acid-sensitive microbes are destroyed by hydrochloric acid. Anaerobic bacteria in the oral cavity include: ''Actinomyces'', ''Arachnia (bacterium), Arachnia'' (''Propionibacterium propionicus''), ''Bacteroides'', ''Bifidobacterium'', ''Eubacterium'', ''Fusobacterium'', ''Lactobacillus'', ''Leptotrichia buccalis, Leptotrichia'', ''Peptococcus'', ''Peptostreptococcus'', ''Propionibacterium'', ''Selenomonas'', ''Treponema'', and ''Veillonella''. The most commonly found protists are ''Entamoeba gingivalis'' and ''Trichomo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Endospore
An endospore is a dormant, tough, and non-reproductive structure produced by some bacteria in the phylum Bacillota. The name "endospore" is suggestive of a spore or seed-like form (''endo'' means 'within'), but it is not a true spore (i.e., not an offspring). It is a stripped-down, dormant form to which the bacterium can reduce itself. Endospore formation is usually triggered by a lack of nutrients, and usually occurs in Gram-positive bacteria. In endospore formation, the bacterium divides within its cell wall, and one side then engulfs the other. Endospores enable bacteria to lie dormant for extended periods, even centuries. There are many reports of spores remaining viable over 10,000 years, and revival of spores millions of years old has been claimed. There is one report of viable spores of '' Bacillus marismortui'' in salt crystals approximately 25 million years old. When the environment becomes more favorable, the endospore can reactivate itself into a vegetative state. Mos ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bacillus (shape)
Bacterial cellular morphologies are the shapes that are characteristic of various types of bacteria and often key to their identification. Their direct examination under a light microscope enables the classification of these bacteria (and archaea). Generally, the basic morphologies are spheres (coccus) and round-ended cylinders or rod shaped (bacillus). But, there are also other morphologies such as helically twisted cylinders (example '' Spirochetes''), cylinders curved in one plane (selenomonads) and unusual morphologies (the square, flat box-shaped cells of the Archaean genus '' Haloquadratum)''. Other arrangements include pairs, tetrads, clusters, chains and palisades. Types Coccus A coccus (plural ''cocci'', from the Latin ''coccinus'' (scarlet) and derived from the Greek ''kokkos'' (berry)), is any microorganism (usually bacteria) whose overall shape is spherical or nearly spherical. Coccus refers to the shape of the bacteria and can contain multiple genera, such as st ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Scanning Electron Micrograph
A scanning electron microscope (SEM) is a type of electron microscope that produces images of a sample by scanning the surface with a focused beam of electrons. The electrons interact with atoms in the sample, producing various signals that contain information about the surface topography and composition. The electron beam is scanned in a raster scan pattern, and the position of the beam is combined with the Intensity (physics), intensity of the detected signal to produce an image. In the most common SEM mode, secondary electrons emitted by atoms excited by the electron beam are detected using a secondary electron detector (Everhart–Thornley detector). The number of secondary electrons that can be detected, and thus the signal intensity, depends, among other things, on specimen topography. Some SEMs can achieve resolutions better than 1 Nanometre, nanometer. Specimens are observed in high vacuum in a Convention (norm), conventional SEM, or in low vacuum or wet conditions in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vaginal Flora
Vaginal flora, vaginal microbiota or vaginal microbiome are the microorganisms that colonize the vagina. They were discovered by the German gynecologist Albert Döderlein in 1892 and are part of the overall human flora. The amount and type of bacteria present have significant implications for an individual's overall health. The primary colonizing bacteria of a healthy individual are of the genus ''Lactobacillus'', such as ''Lactobacillus crispatus, L. crispatus'', and the lactic acid they produce is thought to protect against infection by pathogenic species. Lactobacilli The primary colonizing bacteria of a healthy individual are of the genus ''Lactobacillus'' (90–95%), the most common being ''Lactobacillus crispatus, L. crispatus'', ''Lactobacillus iners, L. iners'', ''Lactobacillus jensenii, L. jensenii'', and ''Lactobacillus gasseri, L. gasseri''. Since the first description of lactobacilli by Döderlein, lactobacilli have been generally considered the gatekeepers of the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Skin Flora
Skin flora, also called skin microbiota, refers to microbiota (community (ecology), communities of microorganisms) that reside on the skin, typically human skin. Many of them are bacterium, bacteria of which there are around 1,000 species upon human skin from nineteen Phylum, phyla. Most are found in the superficial layers of the Epidermis (skin), epidermis and the upper parts of hair follicles. Skin flora is usually non-pathogenic, and either commensalism, commensal (are not harmful to their host) or Mutualism (biology), mutualistic (offer a benefit). The benefits bacteria can offer include preventing transient pathogenic organisms from Infection#Colonization, colonizing the skin surface, either by competing for nutrients, secreting chemicals against them, or stimulating the skin's immune system. However, resident microbes can cause skin diseases and enter the blood system, creating life-threatening diseases, particularly in immunosuppressed people. A major non-human skin flora ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gut Flora
Gut microbiota, gut microbiome, or gut flora are the microorganisms, including bacteria, archaea, fungi, and viruses, that live in the digestive tracts of animals. The gastrointestinal metagenome is the aggregate of all the genomes of the gut microbiota. The gut is the main location of the human microbiome. The gut microbiota has broad impacts, including effects on colonization, resistance to pathogens, maintaining the intestinal epithelium, metabolizing dietary and pharmaceutical compounds, controlling immune function, and even behavior through the gut–brain axis. The microbial composition of the gut microbiota varies across regions of the digestive tract. The colon contains the highest microbial density of any human-associated microbial community studied so far, representing between 300 and 1000 different species. Bacteria are the largest and to date, best studied component and 99% of gut bacteria come from about 30 or 40 species. About 55% of the dry mass of feces ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Opportunistic Infection
An opportunistic infection is an infection that occurs most commonly in individuals with an immunodeficiency disorder and acts more severe on those with a weakened immune system. These types of infections are considered serious and can be caused by a variety of pathogens including viruses, bacteria, fungi, and parasites. Under normal conditions, such as in humans with uncompromised immune systems, an opportunistic infection would be less likely to cause significant harm and would typically result in a mild infection or no effect at all. These opportunistic infections can stem from a variety of sources, such as a weakened immune system (caused by human immunodeficiency virus and acquired immunodeficiency syndrome), when being treated with immunosuppressive drugs (as in cancer treatment), when a microbiome is altered (such as a disruption in gut microbiota), or when integumentary barriers are breached (as in penetrating trauma). Opportunistic infections can contribute to antimic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Livestock
Livestock are the Domestication, domesticated animals that are raised in an Agriculture, agricultural setting to provide labour and produce diversified products for consumption such as meat, Egg as food, eggs, milk, fur, leather, and wool. The term is sometimes used to refer solely to animals which are raised for consumption, and sometimes used to refer solely to farmed ruminants, such as cattle, sheep, and goats. The breeding, maintenance, slaughter and general subjugation of livestock called ''animal husbandry'', is a part of modern agriculture and has been practiced in many cultures since humanity's transition to farming from hunter-gatherer lifestyles. Animal husbandry practices have varied widely across cultures and periods. It continues to play a major economic and cultural role in numerous communities. Livestock farming practices have largely shifted to intensive animal farming. Intensive animal farming increases the yield of the various commercial outputs, but also nega ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
