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A perfectly reasonable definition of a ligand from Wikipedia: In biochemistry and pharmacology, a ligand is a substance that forms a complex with a biomolecule to serve a biological purpose. A ligand can be anything, so long as it binds to a biomolecule. Often, the ligand is a small molecule or peptide, and the thing that it binds to is a protein. On ...


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You are right the compounds provoking this burning/tingling sensation is called allyl isothiocyanate. We (human) perceive these compounds in two different ways when ingested, namely via the gustatory and olfactory systems. The molecular receptor sensing isothiocyanates is called the transient receptor channel A1 (TRPA1) [ref]. Here a simplistic view of how ...


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These kind of equations (the Michaelis-Menten [MM] like term) denote saturation kinetics. The basic mechanistic assumption behind saturation kinetics is this: A rate (of lets say product formation) is dependent on the concentration of a molecule such that the rate increases linearly with increase in the concentration of the molecule. Example 1: Substrate ...


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The notation you are referring to is a way to express the elongation of a nucleotide strand (Fig. 1). dNTP + dNMP(n) → dNMP(n+1) + PPi means Existing strand + deoxynucleotidetriphosphate → elongated-strand + pyrophospate. Fig. 1. Elongation of DNA. Source: Concepts in Genetics. This reaction holds for DNA replication as well as ...


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In biology ligand is a very broad term. Everything is called a ligand that has a receptor for it, regardless whether it is free or membrane-bound. There is very much sense in membrane bound ligands, because many cells in our body are capable of actively moving around (for example T-cells). Cells can use signal transduction by direct cell-to-cell contact - ...


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Another small addition There is class of oxidoreductases called oxygenases which incorporate molecular oxygen into the substrates and not just use it as an electron acceptor like in oxidases (note that the terminal enzyme in ETC is an oxidase and there are other such oxidases). In other words, oxygen is not a cofactor but a co-substrate. Oxygenases are ...


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DNA in pure water. The only time that nucleic acids would encounter pure water would be in a laboratory setting--for example after an oligonucleotide is synthesized in vitro, the protecting groups are removed from the reactive atoms in the finished sequence and the final product is cleaved from the supporting matrix. At that point you can lyophilize ...


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Looks like some parasitoid wasps have zinc coated barbs on their ovipositors which may function to help them bore through wood and lay their eggs. Here's the blog entry about it on IFL Science, and the original article: parasitoid ovipositor specimens had a weight percentage of zinc of 7.19±3.8% (N=42) in the tip regions, which was significantly higher ...


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What does it mean for an element to be mobile or immobile in plants? Generally speaking, mobile elements are those that can be moved from older to newer tissue in the plant, while immobile ones cannot be. For example, calcium is incorporated into the cell wall, so it is immobile; it cannot be relocated later. Plants with a deficiency of mobile elements ...


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There appears to be either a typo or transcription error in your textbook. According to this Nuffield Foundation and Royal Society of Chemistry article Molecules of most detergents and soaps are long chain hydrocarbon molecules with an ionic group at one end, usually carrying a negative charge, thus making it an anion. This charge is balanced by ...


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Surface tension is about how much energy you need to create new surface between not mixing materials e.g. water and lipids. Surfactants like bile makes this easier (lowers the energy required). So they can form small bubbles of lipids: micelles, which can be handled much easier by the digestive system. Another usage of surfactants to make foams, creams, ...


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Given your background (not a biologist or chemist) you would probably find the introductory material in a biochemistry "lite" textbook more accessible/useful than a hardcore text for specialists. As a co-author of a biochemistry textbook, I can tell you that there are essentially three different classes, or types of texts. Comprehensive textbooks, of ...


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There are stable ubiquitinated proteins in mammalian cell lysates even if active proteosomes exist in cells. First, you might want to make sure that the antibody is applicable to WB. Then, you would ask if your WB system using the antibody works. You could optimize the condition using just 1D SDS-PAGE followed by WB. For the condition for isoelectric ...


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Your question is answered in the paper, the protein likely exists as a homodimer in vivo and denaturation (such as performed with SDS PAGE -> Western Blot) separates the dimers into monomers: "To determine the quaternary structure, size exclusion high-performance liquid chromatography was performed using an Agilent 1100 series high-performance liquid ...



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