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Saporin
Saporin is a protein that is useful in biological research applications, especially studies of behavior. Saporins are so-called ribosome inactivating proteins (RIPs), due to its N-glycosidase activity, from the seeds of ''Saponaria officinalis'' (common name: soapwort). It was first described by Fiorenzo Stirpe and his colleagues in 1983 in an article that illustrated the unusual stability of the protein. Among the RIPs are some of the most toxic molecules known, such as ricin and abrin. Each of these toxins contain a second protein subunit, which inserts the RIP into a cell, enabling it to enzymatically inactivate the ribosomes, shutting down protein synthesis, stopping basic cell functions, resulting in cell death, and eventually causing death of the victim. Saporin has no chain capable of inserting it into the cell. Thus it and the soapwort plant are safe to handle. This has aided its use in research. If given a method of entry into the cell, saporin becomes a very potent to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Saponins
Saponins (Latin ''sapon'', 'soap' + ''-in'', 'one of') are bitter-tasting, usually toxic plant-derived secondary metabolites. They are Organic compound, organic chemicals that become foamy when agitated in water and have high Molar mass, molecular weight. They are present in a wide range of plant species throughout the bark, leaves, stems, roots and flowers but particularly in Saponaria, soapwort (genus ''Saponaria''), a flowering plant, the Quillaja saponaria, soapbark tree (''Quillaja saponaria''), Agrostemma githago, common corn-cockle (''Agrostemma githago'' L.), Gypsophila, baby's breath (Gypsophila, ''Gypsophila'' spp.) and soybeans (''Soybean, Glycine max'' L.). They are used in soaps, medicines (e.g. drug adjuvants), fire extinguishers, dietary supplements, steroid synthesis, and in carbonated beverages (for example, being responsible for maintaining the head on root beer). Saponins are both water and fat soluble, which gives them their useful soap properties. Some example ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ribosome Inactivating Protein
A ribosome-inactivating protein (RIP) is a protein synthesis inhibitor that acts at the eukaryotic ribosome. This protein family describes a large family of such proteins that work by acting as rRNA N-glycosylase (EC 3.2.2.22). They inactivate 60S ribosomal subunits by an N-glycosidic cleavage, which releases a specific adenine base from the sugar-phosphate backbone of 28S rRNA. RIPs exist in bacteria and plants. Members of the family include shiga toxins, and type I (e.g. trichosanthin and luffin) and type II (e.g. ricin, agglutinin, and abrin) ribosome inactivating proteins (RIPs). All these toxins are structurally related. RIPs have been of considerable interest because of their potential use, conjugated with monoclonal antibodies, as immunotoxins to treat cancers. Further, trichosanthin has been shown to have potent activity against HIV-1-infected T cells and macrophages. Elucidation of the structure-function relationships of RIPs has therefore become a major research effor ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
David Flavell
David J. Flavell is a British academic research scientist who specializes in the development of antibody-based treatments for adults and children with various forms of leukaemia and lymphoma. Early life Born in Southport, Lancashire, in 1953, he obtained his bachelor's degree in applied Biology from Liverpool in 1975, and his Ph.D. in cancer immunology from Sheffield in 1978. He has held posts at the University of Sheffield (1975–78), Mahidol University, Bangkok, Thailand (1978–79), The University of London, London School of Hygiene and Tropical Medicine (1979–1983) and the University of Southampton Medical School (1984–2005). He became a member of The Royal Society of Pathologists in 1997, and later a Fellow of the same Royal Society in 2004. Career With his wife Sopsamorn and two other couples, Flavell started a children's leukaemia A child () is a human being between the stages of childbirth, birth and puberty, or between the Development of the human bo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gelonin
Gelonin is a type 1 ribosome-inactivating protein and toxin of approximately 30 kDa found in the seeds of the Himalayan plant Gelonium multiflorum. In cell (biology), cell-free systems gelonin exerts powerful N-glycosidase activity on the 28S rRNA unit of eukaryotic ribosomes by cleaving out adenine at the 4324 site. Gelonin lacks carbohydrate-binding domains so it is unable to cross the plasma membrane, making it highly effective only in cell free systems. Structure Gelonin is a 30 kDa protein. Gelonin is a dimer, consisting of two identical monomers. Each monomer is composed of 251 amino acids, for a total of 502 residues. Gelonin is classified as an (α + β) protein, as its secondary structure consists of both beta sheets and alpha helices. Each monomer’s first 100 amino acids form 10 beta sheets, while their last 151 amino acids form 10 alpha helices. Gelonin’s two dimers are stabilized by hydrophobic interactions and hydrogen bonds. Specifically, the Asn22, Arg178, Asn1 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Protein
Proteins are large biomolecules and macromolecules that comprise one or more long chains of amino acid residue (biochemistry), residues. Proteins perform a vast array of functions within organisms, including Enzyme catalysis, catalysing metabolic reactions, DNA replication, Cell signaling, responding to stimuli, providing Cytoskeleton, structure to cells and Fibrous protein, organisms, and Intracellular transport, transporting molecules from one location to another. Proteins differ from one another primarily in their sequence of amino acids, which is dictated by the Nucleic acid sequence, nucleotide sequence of their genes, and which usually results in protein folding into a specific Protein structure, 3D structure that determines its activity. A linear chain of amino acid residues is called a polypeptide. A protein contains at least one long polypeptide. Short polypeptides, containing less than 20–30 residues, are rarely considered to be proteins and are commonly called pep ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Immunotoxins
An immunotoxin is an artificial protein consisting of a targeting portion linked to a toxin. When the protein binds to that cell, it is taken in through endocytosis, and the toxin kills the cell. They are used for the treatment of some kinds of cancer and a few viral infections. Design These chimeric proteins are usually made of a modified antibody or antibody fragment, attached to a fragment of a toxin. The targeting portion is composed of the Fab portion of an antibody that targets a specific cell type. The toxin is usually an AB toxin, a cytotoxic protein derived from a bacterial or plant protein, from which the natural binding domain has been removed so that the Fv directs the toxin to the antigen on the target cell. Sometimes recombinant fusion proteins containing a toxin and a growth factor are also referred to as recombinant immunotoxins, although they do not contain an antibody fragment. A more specific name for this latter kind of protein is recombinant fusion toxin. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Proteolysis
Proteolysis is the breakdown of proteins into smaller polypeptides or amino acids. Protein degradation is a major regulatory mechanism of gene expression and contributes substantially to shaping mammalian proteomes. Uncatalysed, the hydrolysis of peptide bonds is extremely slow, taking hundreds of years. Proteolysis is typically catalysed by cellular enzymes called proteases, but may also occur by intra-molecular digestion. Proteolysis in organisms serves many purposes; for example, digestive enzymes break down proteins in food to provide amino acids for the organism, while proteolytic processing of a polypeptide chain after its synthesis may be necessary for the production of an active protein. It is also important in the regulation of some physiological and cellular processes including apoptosis, as well as preventing the accumulation of unwanted or misfolded proteins in cells. Consequently, abnormality in the regulation of proteolysis can cause diseases. Proteolysis can also ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Denaturation (biochemistry)
In biochemistry, denaturation is a process in which proteins or nucleic acids lose folded structure present in their native state due to various factors, including application of some external stress or compound, such as a strong acid or base, a concentrated inorganic salt, an organic solvent (e.g., alcohol or chloroform), agitation, radiation, or heat. If proteins in a living cell are denatured, this results in disruption of cell activity and possibly cell death. Protein denaturation is also a consequence of cell death. Denatured proteins can exhibit a wide range of characteristics, from conformational change and loss of solubility or dissociation of cofactors to aggregation due to the exposure of hydrophobic groups. The loss of solubility as a result of denaturation is called ''coagulation''. Denatured proteins, e.g., metalloenzymes, lose their 3D structure or metal cofactor, and therefore, cannot function. Proper protein folding is key to whether a globular or memb ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alzheimer's Disease
Alzheimer's disease (AD) is a neurodegenerative disease and the cause of 60–70% of cases of dementia. The most common early symptom is difficulty in remembering recent events. As the disease advances, symptoms can include problems with language, disorientation (including easily getting lost), mood swings, loss of motivation, self-neglect, and behavioral issues. As a person's condition declines, they often withdraw from family and society. Gradually, bodily functions are lost, ultimately leading to death. Although the speed of progression can vary, the average life expectancy following diagnosis is three to twelve years. The causes of Alzheimer's disease remain poorly understood. There are many environmental and genetic risk factors associated with its development. The strongest genetic risk factor is from an allele of apolipoprotein E. Other risk factors include a history of head injury, clinical depression, and high blood pressure. The progression of the di ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Forebrain
In the anatomy of the brain of vertebrates, the forebrain or prosencephalon is the rostral (forward-most) portion of the brain. The forebrain controls body temperature, reproductive functions, eating, sleeping, and the display of emotions. Vesicles of the forebrain (prosencephalon), the midbrain (mesencephalon), and hindbrain (rhombencephalon) are the three primary brain vesicles during the early development of the nervous system. At the five-vesicle stage, the forebrain separates into the diencephalon (thalamus, hypothalamus, subthalamus, and epithalamus) and the telencephalon which develops into the cerebrum. The cerebrum consists of the cerebral cortex, underlying white matter, and the basal ganglia. In humans, by 5 weeks in utero it is visible as a single portion toward the front of the fetus. At 8 weeks in utero, the forebrain splits into the left and right cerebral hemispheres. When the embryonic forebrain fails to divide the brain into two lobes, it results i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Animal Testing
Animal testing, also known as animal experimentation, animal research, and ''in vivo'' testing, is the use of animals, as model organisms, in experiments that seek answers to scientific and medical questions. This approach can be contrasted with field studies in which animals are observed in their natural environments or habitats. Experimental research with animals is usually conducted in universities, medical schools, pharmaceutical companies, defense establishments, and commercial facilities that provide animal-testing services to the industry. The focus of animal testing varies on a continuum from Basic research, pure research, focusing on developing fundamental knowledge of an organism, to applied research, which may focus on answering some questions of great practical importance, such as finding a cure for a disease. Examples of applied research include testing disease treatments, breeding, defense research, and Toxicology testing, toxicology, including Testing cosmetics ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vanderbilt University
Vanderbilt University (informally Vandy or VU) is a private university, private research university in Nashville, Tennessee, United States. Founded in 1873, it was named in honor of shipping and railroad magnate Cornelius Vanderbilt, who provided the school its initial $1 million endowment in the hopes that his gift and the greater work of the university would help to heal the sectional wounds inflicted by the American Civil War. Vanderbilt is a founding member of the Southeastern Conference and has been the conference's only private school since 1966. The university comprises ten schools and enrolls nearly 13,800 students from the US and 70 foreign countries. Vanderbilt is Carnegie Classification of Institutions of Higher Education, classified among "R1: Doctoral Universities – Very high research activity". Several research centers and institutes are affiliated with the university, including the Robert Penn Warren, Robert Penn Warren Center for the Humanities, the Freedom Foru ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
