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Corynebacterium Ureicelerivorans
''Corynebacterium'' () is a genus of Gram-positive bacteria and most are aerobic. They are bacilli (rod-shaped), and in some phases of life they are, more specifically, club-shaped, which inspired the genus name ('' coryneform'' means "club-shaped"). They are widely distributed in nature in the microbiota of animals (including the human microbiota) and are mostly innocuous, most commonly existing in commensal relationships with their hosts. Some, such as '' C. glutamicum'', are commercially and industrially useful. Others can cause human disease, including, most notably, diphtheria, which is caused by '' C. diphtheriae''. Like various species of microbiota (including their relatives in the genera '' Arcanobacterium'' and '' Trueperella''), they are usually not pathogenic, but can occasionally capitalize opportunistically on atypical access to tissues (via wounds) or weakened host defenses. Taxonomy The genus ''Corynebacterium'' was created by Lehmann and Neumann in 189 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Corynebacterium Ulcerans
''Corynebacterium ulcerans'' is a rod-shaped, aerobic, and Gram-positive bacterium. Most ''Corynebacterium'' species are harmless, but some cause serious illness in humans, especially in immunocompromised humans. ''C. ulcerans'' has been known to cause diphtheria and diphtheria-like infections in patients. Previously thought to simply be contaminants recovered from diphtheria patients, “ coryneform” or “diphtheroids” are now believed to be the ''cause'' of such infections. Disease Increasingly over the past few decades, ''C. ulcerans'' has been recognized as an emerging pathogen in over six countries across the globe including the United States, the United Kingdom, and Japan. '' C. diphtheriae'' is the causative agent of classical diphtheria, and ''C. ulcerans'' has been found to carry the same gene that codes for the diphtheria toxin. After swabbing lesions on a 53-year-old woman in Germany who experienced swelling of her pharynx and who developed a whitish pseudomem ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pathogen
In biology, a pathogen (, "suffering", "passion" and , "producer of"), in the oldest and broadest sense, is any organism or agent that can produce disease. A pathogen may also be referred to as an infectious agent, or simply a Germ theory of disease, germ. The term ''pathogen'' came into use in the 1880s. Typically, the term ''pathogen'' is used to describe an ''infectious'' microorganism or agent, such as a virus, bacterium, protozoan, prion, viroid, or fungus. Small animals, such as helminths and insects, can also cause or Transmission (medicine), transmit disease. However, these animals are usually referred to as parasites rather than pathogens. The scientific study of microscopic organisms, including microscopic pathogenic organisms, is called microbiology, while parasitology refers to the scientific study of parasites and the organisms that host them. There are several pathways through which pathogens can invade a host. The principal pathways have different episodic time ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nocardia
''Nocardia'' is a genus of weakly staining Gram-positive, catalase, catalase-positive, rod-shaped bacteria. It forms partially acid-fast beaded branching filaments (appearing similar to fungi, but being truly bacteria). It contains a total of 85 species. Some species are nonpathogenic, while others are responsible for nocardiosis. ''Nocardia'' species are found worldwide in soil rich in organic matter. In addition, they are oral microflora found in healthy human Gums, gingiva, as well as periodontal pockets. Most ''Nocardia'' infections are acquired by inhalation of the bacteria or through traumatic introduction through openings in Epithelium, epithelial barriers. Culture and staining ''Nocardia'' colonies have a variable appearance, but most species appear to have aerial hyphae when viewed with a dissecting microscope, particularly when they have been grown on nutritionally limiting media. ''Nocardia'' grow slowly on nonselective culture media, and are strict Aerobic metaboli ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mycobacterium
''Mycobacterium'' is a genus of over 190 species in the phylum Actinomycetota, assigned its own family, Mycobacteriaceae. This genus includes pathogens known to cause serious diseases in mammals, including tuberculosis (''Mycobacterium tuberculosis, M. tuberculosis'') and leprosy (''Mycobacterium leprae, M. leprae'') in humans. The Greek language, Greek prefix ''myco-'' means 'fungus', alluding to this genus' Mold (fungus), mold-like colony surfaces. Since this genus has cell walls with a waxy lipid-rich outer layer containing high concentrations of mycolic acid, acid-fast staining is used to emphasize their resistance to acids, compared to other cell types. Mycobacterial species are generally aerobic, non-motile, and capable of growing with minimal nutrition. The genus is divided based on each species' pigment production and growth rate. While most ''Mycobacterium'' species are non-pathogenic, the genus' characteristic complex cell wall contributes to evasion from host defenses. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Arthrobacter
''Arthrobacter'' (from the Greek, "jointed small stick”) is a genus of bacterium, bacteria that is commonly found in soil. All species in this genus are Gram-positive obligate aerobes that are bacterial shape, rods during exponential growth and bacterial shape, cocci in their Stationary phase (biology), stationary phase. ''Arthrobacter'' have a distinctive method of cell division called "snapping division" or reversion (microbiology), reversion in which the outer bacterial cell wall ruptures at a joint. Description ''Arthrobacter'' can be grown on mineral salts pyridone broth, where colonies have a greenish metallic center on incubated at . Under the microscope, ''Arthrobacter'' appear as rods when rapidly dividing, and cocci when in stationary phase. Dividing cells may also appear as chevrons ("V" shapes). Other notable characteristics are that it can use pyridone as its sole carbon source, and that its cocci are resistant to desiccation and starvation. Use in industry ''Arth ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cytosine
Cytosine () (symbol C or Cyt) is one of the four nucleotide bases found in DNA and RNA, along with adenine, guanine, and thymine ( uracil in RNA). It is a pyrimidine derivative, with a heterocyclic aromatic ring and two substituents attached (an amine group at position 4 and a keto group at position 2). The nucleoside of cytosine is cytidine. In Watson–Crick base pairing, it forms three hydrogen bonds with guanine. History Cytosine was discovered and named by Albrecht Kossel and Albert Neumann in 1894 when it was hydrolyzed from calf thymus tissues. A structure was proposed in 1903, and was synthesized (and thus confirmed) in the laboratory in the same year. In 1998, cytosine was used in an early demonstration of quantum information processing when Oxford University researchers implemented the Deutsch–Jozsa algorithm on a two qubit nuclear magnetic resonance quantum computer (NMRQC). In March 2015, NASA scientists reported the formation of cytosine, alon ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Guanine
Guanine () (symbol G or Gua) is one of the four main nucleotide bases found in the nucleic acids DNA and RNA, the others being adenine, cytosine, and thymine ( uracil in RNA). In DNA, guanine is paired with cytosine. The guanine nucleoside is called guanosine. With the formula C5H5N5O, guanine is a derivative of purine, consisting of a fused pyrimidine- imidazole ring system with conjugated double bonds. This unsaturated arrangement means the bicyclic molecule is planar. Properties Guanine, along with adenine and cytosine, is present in both DNA and RNA, whereas thymine is usually seen only in DNA, and uracil only in RNA. Guanine has multiple tautomeric forms. For the imidazole ring, the proton can reside on either nitrogen. For the pyrimidine ring, the ring N-H can center can reside on either of the ring nitrogens. The latter tautomer does not apply to nucleoside or nucleotide versions of guanine. It binds to cytosine through three hydrogen bonds. In cytosine, t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eubacteria
Bacteria (; : bacterium) 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 the air, 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 mutualistic, commensal ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
16S RRNA
16S ribosomal RNA (or 16Svedberg, S rRNA) is the RNA component of the 30S subunit of a prokaryotic ribosome (SSU rRNA). It binds to the Shine-Dalgarno sequence and provides most of the SSU structure. The genes coding for it are referred to as 16S rRNA genes and are used in reconstructing phylogenetics, phylogenies, due to the slow rates of evolution of this region of the gene. Carl Woese and George E. Fox were two of the people who pioneered the use of 16S rRNA in phylogenetics in 1977. Multiple sequences of the 16S rRNA gene can exist within a single bacterium. Terminology The descriptor ''16S'' refers to the size of these ribosomal subunits as reflected indirectly by the speed at which they sediment when samples are centrifuged. Thus ''16S'' means 16 Svedberg, Svedburg units. Functions * Like the 23S ribosomal RNA, large (23S) ribosomal RNA, it has a structural role, acting as a scaffold defining the positions of the ribosomal proteins. * The Directionality (molecular biolo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Morphology (biology)
Morphology (from Ancient Greek μορφή (morphḗ) "form", and λόγος (lógos) "word, study, research") is the study of the form and structure of organisms and their specific structural features. This includes aspects of the outward appearance (shape, structure, color, pattern, size), as well as the form and structure of internal parts like bones and organs, i.e., anatomy. This is in contrast to physiology, which deals primarily with function. Morphology is a branch of life science dealing with the study of the overall structure of an organism or taxon and its component parts. History The etymology of the word "morphology" is from the Ancient Greek (), meaning "form", and (), meaning "word, study, research". While the concept of form in biology, opposed to function, dates back to Aristotle (see Aristotle's biology), the field of morphology was developed by Johann Wolfgang von Goethe (1790) and independently by the German anatomist and physiologist Karl Fried ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Taxonomy (biology)
In biology, taxonomy () is the science, scientific study of naming, defining (Circumscription (taxonomy), circumscribing) and classifying groups of biological organisms based on shared characteristics. Organisms are grouped into taxon, taxa (singular: taxon), and these groups are given a taxonomic rank; groups of a given rank can be aggregated to form a more inclusive group of higher rank, thus creating a taxonomic hierarchy. The principal ranks in modern use are domain (biology), domain, kingdom (biology), kingdom, phylum (''division'' is sometimes used in botany in place of ''phylum''), class (biology), class, order (biology), order, family (biology), family, genus, and species. The Swedish botanist Carl Linnaeus is regarded as the founder of the current system of taxonomy, having developed a ranked system known as Linnaean taxonomy for categorizing organisms. With advances in the theory, data and analytical technology of biological systematics, the Linnaean system has transfo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Immunodeficiency
Immunodeficiency, also known as immunocompromise, is a state in which the immune system's ability to fight infectious diseases and cancer is compromised or entirely absent. Most cases are acquired ("secondary") due to extrinsic factors that affect the patient's immune system. Examples of these extrinsic factors include HIV infection and environmental factors, such as nutrition. Immunocompromisation may also be due to genetic diseases/flaws such as SCID. In clinical settings, immunosuppression by some drugs, such as steroids, can either be an adverse effect or the intended purpose of the treatment. Examples of such use is in organ transplant surgery as an anti- rejection measure and in patients with an overactive immune system, as in autoimmune diseases. Some people are born with intrinsic defects in their immune system, or primary immunodeficiency. A person who has an immunodeficiency of any kind is said to be immunocompromised. An immunocompromised individual may par ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
