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Streptobacillus Moniliformis
''Streptobacillus moniliformis'' is a non-motile, Gram-negative rod-shaped bacterium that is a member of the family Leptotrichiaceae. The genome of ''S. moniliformis'' is one of two completed sequences of the order Fusobacteriales. Its name comes from the Greek word ''streptos'' for "curved" or "twisted", and the Latin words ''bacillus'' meaning "small rod" and ''moniliformis'' for "necklace". ''S. moniliformis'' is microaerophilic, requiring less oxygen than is present in the atmosphere for its growth. Background History ''S. moniliformis'' was first isolated from a rat-bitten man in 1914 by German microbiologist H. Schottmüller, who described it as ''Streptothrix muris ratti''. In the United States during the year 1916, ''S. moniliformis'' was determined to be the causative source of rat-bite fever. Microbiology Some isolates of ''S. moniliformis'' have been collected from the upper respiratory tract of domestic and wild rats. Two known variants of ''S. moniliformis' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Colony (biology)
In biology, a colony is composed of two or more conspecific individuals living in close association with, or connected to, one another. This association is usually for mutual benefit such as stronger defense or the ability to attack bigger prey. Colonies can form in various shapes and ways depending on the organism involved. For instance, the bacterial colony is a cluster of identical cells (clones). These colonies often form and grow on the surface of (or within) a solid medium, usually derived from a single parent cell. Colonies, in the context of development, may be composed of two or more unitary (or solitary) organisms or be modular organisms. Unitary organisms have determinate development (set life stages) from zygote to adult form and individuals or groups of individuals (colonies) are visually distinct. Modular organisms have indeterminate growth forms (life stages not set) through repeated iteration of genetically identical modules (or individuals), and it can be diffi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Elbow
The elbow is the region between the arm and the forearm that surrounds the elbow joint. The elbow includes prominent landmarks such as the olecranon, the cubital fossa (also called the chelidon, or the elbow pit), and the lateral and the medial epicondyles of the humerus. The elbow joint is a hinge joint between the arm and the forearm; more specifically between the humerus in the upper arm and the radius and ulna in the forearm which allows the forearm and hand to be moved towards and away from the body. The term ''elbow'' is specifically used for humans and other primates, and in other vertebrates forelimb plus joint is used. The name for the elbow in Latin is ''cubitus'', and so the word cubital is used in some elbow-related terms, as in ''cubital nodes'' for example. Structure Joint The elbow joint has three different portions surrounded by a common joint capsule. These are joints between the three bones of the elbow, the humerus of the upper arm, and the radius an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Peritonsillar Abscess
Peritonsillar abscess (PTA), also known as quinsy, is an accumulation of pus due to an infection behind the tonsil. Symptoms include fever, throat pain, trouble opening the mouth, and a change to the voice. Pain is usually worse on one side. Complications may include blockage of the airway or aspiration pneumonitis. PTA is typically due to infection by a number of types of bacteria. Often it follows streptococcal pharyngitis. They do not typically occur in those who have had a tonsillectomy. Diagnosis is usually based on the symptoms. Medical imaging may be done to rule out complications. Treatment is by removing the pus, antibiotics, sufficient fluids, and pain medication. Steroids may also be useful. Admission to hospital is generally not needed. In the United States about 3 per 10,000 people per year are affected. Young adults are most commonly affected. Signs and symptoms Physical signs of a peritonsillar abscess include redness and swelling in the tonsillar area of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Abscess
An abscess is a collection of pus that has built up within the tissue of the body. Signs and symptoms of abscesses include redness, pain, warmth, and swelling. The swelling may feel fluid-filled when pressed. The area of redness often extends beyond the swelling. Carbuncles and boils are types of abscess that often involve hair follicles, with carbuncles being larger. They are usually caused by a bacterial infection. Often many different types of bacteria are involved in a single infection. In many areas of the world, the most common bacteria present is ''methicillin-resistant Staphylococcus aureus''. Rarely, parasites can cause abscesses; this is more common in the developing world. Diagnosis of a skin abscess is usually made based on what it looks like and is confirmed by cutting it open. Ultrasound imaging may be useful in cases in which the diagnosis is not clear. In abscesses around the anus, computer tomography (CT) may be important to look for deeper infection. St ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Strain (biology)
In biology, a strain is a genetic variant, a subtype or a culture within a biological species. Strains are often seen as inherently artificial concepts, characterized by a specific intent for genetic isolation. This is most easily observed in microbiology where strains are derived from a single cell colony and are typically quarantined by the physical constraints of a Petri dish. Strains are also commonly referred to within virology, botany, and with rodents used in experimental studies. Microbiology and virology It has been said that "there is no universally accepted definition for the terms 'strain', ' variant', and 'isolate' in the virology community, and most virologists simply copy the usage of terms from others". A strain is a genetic variant or subtype of a microorganism (e.g., a virus, bacterium or fungus). For example, a "flu strain" is a certain biological form of the influenza or "flu" virus. These flu strains are characterized by their differing isoforms of sur ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Conserved Signature Indels
Conserved signature inserts and deletions (CSIs) in protein sequences provide an important category of molecular markers for understanding phylogenetic relationships. CSIs, brought about by rare genetic changes, provide useful phylogenetic markers that are generally of defined size and they are flanked on both sides by conserved regions to ensure their reliability. While indels can be arbitrary inserts or deletions, CSIs are defined as only those protein indels that are present within conserved regions of the protein. The CSIs that are restricted to a particular clade or group of species, generally provide good phylogenetic markers of common evolutionary descent. Due to the rarity and highly specific nature of such changes, it is less likely that they could arise independently by either convergent or parallel evolution (i.e. homoplasy) and therefore are likely to represent synapomorphy. Other confounding factors such as differences in evolutionary rates at different sites or amon ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Internal Transcribed Spacer
Internal transcribed spacer (ITS) is the spacer DNA situated between the small-subunit ribosomal RNA (rRNA) and large-subunit rRNA genes in the chromosome or the corresponding transcribed region in the polycistronic rRNA precursor transcript. ITS across life domains In bacteria and archaea, there is a single ITS, located between the 16S and 23S rRNA genes. Conversely, there are two ITSs in eukaryotes: ITS1 is located between 18S and 5.8S rRNA genes, while ITS2 is between 5.8S and 28S (in opisthokonts, or 25S in plants) rRNA genes. ITS1 corresponds to the ITS in bacteria and archaea, while ITS2 originated as an insertion that interrupted the ancestral 23S rRNA gene. Organization In bacteria and archaea, the ITS occurs in one to several copies, as do the flanking 16S and 23S genes. When there are multiple copies, these do not occur adjacent to one another. Rather, they occur in discrete locations in the circular chromosome. It is not uncommon in bacteria to carry tRN ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ribosomal DNA (rDNA)
Ribosomal DNA (rDNA) is a DNA sequence that codes for ribosomal RNA. These sequences regulate transcription initiation and amplification, and contain both transcribed and non-transcribed spacer segments. In the human genome there are 5 chromosomes with nucleolus organizer regions: the acrocentric chromosomes 13 (RNR1), 14 ( RNR2), 15 ( RNR3), 21 (RNR4) and 22 (RNR5). The genes that are responsible for encoding the various sub-units of rRNA are located across multiple chromosomes in humans. But the genes that encode for rRNA are highly conserved across the domains, with only the copy numbers involved for the genes having varying numbers per species. In Bacteria, Archaea, and chloroplasts the rRNA is composed of different (smaller) units, the large (23S) ribosomal RNA, 16S ribosomal RNA and 5S rRNA. The 16S rRNA is widely used for phylogenetic studies. Eukaryotes The rRNA transcribed from the approximately 600 rDNA repeats forms the most abundant section of RNA found in cell ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
16S Ribosomal RNA
16 S ribosomal RNA (or 16 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 gene and are used in reconstructing 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. Functions * Like the large (23S) ribosomal RNA, it has a structural role, acting as a scaffold defining the positions of the ribosomal proteins. * The 3-end contains the anti- Shine-Dalgarno sequence, which binds upstream to the AUG start codon on the mRNA. The 3-end of 16S RNA binds to the proteins S1 and S21 which are known to be involved in initiation of protein synthesis * Interacts with 23S, aiding in the binding of the two riboso ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sneathia
''Sneathia'' is a Gram-negative, rod-shaped, non- spore-forming and non-motile genus of bacteria from the family of Leptotrichiaceae. Species have been identified as pathogens associated with bacterial vaginosis Bacterial vaginosis (BV) is a disease of the vagina caused by excessive growth of bacteria. Common symptoms include increased vaginal discharge that often smells like fish. The discharge is usually white or gray in color. Burning with urination .... ''Sneathia'' is named of the microbiologist H. A. Snaeth. References Further reading * * * * * Fusobacteriota Bacteria genera {{Bacteria-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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