How can a cell prevent its own protease from digesting all its own proteins and killing itself?
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Cell has it own protective mechanism to distinguih self components from others .such methylation etc.. so that protease reconize self component and donot lyse it
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it does actually kill the bug.\nAfter being eaten, the Bt protein in the insect midgut is dissolved and enzymatically digested to render a solubilized and truncated protein toxin. The toxin then must bind to specific receptors in the gut where it causes pore formation and membrane disruption. The insect dies by septicemia and/or starvation. The efficiency of protein solubilization, truncation and toxin attachment for each insect and toxin combination accounts for the specificity and lethality of certain Bt proteins against different insect pests.
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Pepsin is an enzyme that breaks proteins into amino acids so that they can be absorbed by the intestines.
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This food is entered into the body via the mouth, where enzymes such as lysozyme begin to breakdown the food while it is chewed. When this food is broken down into smaller pieces it can then be swallowed, where it travels down the oesophagus towards the stomach.\n\nThe stomach then continues to break down the foodstuff. The stomach at this point is filled with a type of acid that further breaks down the food, until it is in the duodenum, which is part of the small intestine. It is here where the food is completely broken down, in the following manner:\n\n    * Proteins are broken down into amino acids\n    * Fats into fatty acids\n    * Complex sugars into simple sugars\n\nFrom here, you can see that a complex product (the food you eat) is stripped bare, until the substances that they are broken down to can be used by the body in some way. By breaking down these foodstuffs to their most basic nature, the body can then rebuild these substances as and when required, for example, to create enzymes.\n\nThe Physiological Homeostasis page in the Regulation of Biological Systems tutorial looks at how the body determines when a particular action is required, such as the increase of blood sugar concentration. Also, the Cell Biology Tutorial page ADP and ATP introduces ATP, the body's biological energy, and how it is created, which is continued on the following page.\n\nLink below tells the rest of the story.
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your question doesnt make sense\ni know theres such thing as a DNase, that chews up DNA, but a replication digestive enzyme is like an oxymoron, its two different processes
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Lysosomes are organelles that contain digestive enzymes (acid hydrolases) to digest macromolecules. They are found in both plant and animal cells, and are built in the Golgi apparatus. At pH 4.8, the interior of the lysosomes is more acidic than the cytosol (pH 7). The lysosome single membrane stabilizes the low pH by pumping in protons (H+) from the cytosol, and also protects the cytosol, and therefore the rest of the cell, from the degradative enzymes within the lysosome. The digestive enzymes need the acidic environment of the lysosome to function correctly. For this reason, should a lysosome's acid hydrolases leak into the cytosol, their potential to damage the cell will be reduced, because they will not be at their optimum pH. All these enzymes are produced in the endoplasmic reticulum, and transported and processed through the Golgi apparatus. The Golgi apparatus produces lysosomes by budding. Each acid hydrolase is then targeted to a lysosome by phosphorylation. The lysosome itself is likely safe from enzymatic action due to having proteins in the inner membrane which has a three-dimensional molecular structure that protects vulnerable bonds from enzymatic attack[1
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Some enzymes will be destroyed. But most will still work. Remember every enzyme has has an optimum envornment that it works at i.e. temperature and pH. So when it gets to 112 a lot of enzymes are not working at their best to sustain life.
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B, its specific shape allows specific substrates to bind to the enzyme, thus catalyzing the reaction. If the enzyme DIDN'T have the specific shape, then the substrate would have to take a longer time to break their own bonds themselves.
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You need to buy or create a detergent lysis buffer. Something with, say, Triton X-100 or Igepal and a protease inhibitor cocktail.\n\nYou can buy these ready made or find several recipes quite easily in standard methods textbooks.\n\nOnce you've isolated your cells you need to incubate them on ice with your lysis buffer then macerate the cells using either a vortex or Dounce homogenizer. Spin down the mixture at high speed and the supernatant is your crude whole cell extract.
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it's true because phosphatase prevents vectors from closing in on themselves. This doesn't inhibit cloning but ehances it and allows a greater chance for the insert getting in the plasmid and not just the vector re-closing in on itself.\n\nIf you have any other questions about plasmids, cloning in bacteria, etc. feel free to contact me. I do this in lab almost daily.
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A low pH slows down the enzyme activity. The enzyme present in the stomach is ptyalin. When ptyalin is inactivated, it cannot function.\n\nA little fact of enzyme:\nEnzymes are biological catalysts made of protein. They alter the rate of chemical reactions without themselves being chemically changed at the end of the reaction.\n\nEnzyme combine with the substrate (starch) to form a enzyme-substrate complex. After that, it breaks up into smaller products. The reaction does not change the surface configuration on the enzyme, and therefore can be used to catalyze another reaction. Smaller products makes digestion easier.\n\nSo, when pytalin (enzyme) is inactivated, it cannot go through the procedure as described above.
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Right-the classic idea is that somehow nucleotides got together to form a self-replicating molecule (odds are that it was RNA at first, not DNA), and then these self-replicating molecules began to assemble amino acid chains, which, through uncounted bazillions of reacions (keep in mind whole oceans full of molecules, and billions of years) these amino acid/peptides began to have specific  functions.  The newest theory is that proteins formed (which is fairly easy with the right conditions), and some of these were captured in small mycells (little balls of lipids, which form naturally).  In some of them, the proteins interacted with each other to produce energy-generating reactions, and perhaps served as templates for formation of more of the same protein.  We now know this is as least theoretically possible, because of prion diseases, in which small proteins get into cells and cause generation of the same protein chain, independently of the DNA coding mechanism.  So, under this theory, you have mycells full of enzymes, energy-generating ( as in glycolysis or the TCA cycle) and only later did RNA or DNA come to play a role, as a more convenient and stable way to code for the proteins.  This makes a lot of sense biochemically, and is easier to visualize chemcically than the classic theory.  And, it makes sort of an elegant and chemically poetic argument that the origin of life was the thing that really makes life today-the proteins and the protein reaction-and relegates DNA to just a convenient way for the proteins to replicate.
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they contain an enzyme that inhibits the jelling process
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The Golgi body is responsible for synthesis and packaging of chemicals in the cell. These chemicals are then packaged into thin membranes and used either by the cell or outside of it. \n\nSo, without a Golgi, the cell would not be able to produce the chemicals essential for its life. Hence, the cell would 'die'. \nHowever, if the cell is producing chemicals for external use, the lack of a Golgi body would not 'kill' it, but would only prevent it from fulfilling its function eg - secreting saliva.
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Protein damage through sulfydryl group interactions.  Proteins within the cell are damaged and the cell cannot proliferate (dies).
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In order to perform in vitro analyses, a protein must be purified away from other cellular components. This process usually begins with cell lysis, in which a cell's membrane is disrupted and its internal contents released into a solution known as a crude lysate. The resulting mixture can be purified using ultracentrifugation, which fractionates the various cellular components into fractions containing soluble proteins; membrane lipids and proteins; cellular organelles, and nucleic acids. Precipitation by a method known as salting out can concentrate the proteins from this lysate. Various types of chromatography are then used to isolate the protein or proteins of interest based on properties such as molecular weight, net charge and binding affinity. The level of purification can be monitored using gel electrophoresis if the desired protein's molecular weight is known, by spectroscopy if the protein has distinguishable spectroscopic features, or by enzyme assays if the protein has enzymatic activity.\n\nFor natural proteins, a series of purification steps may be necessary to obtain protein sufficiently pure for laboratory applications. To simplify this process, genetic engineering is often used to add chemical features to proteins that make them easier to purify without affecting their structure or activity. Here, a "tag" consisting of a specific amino acid sequence, often a series of histidine residues (a "His-tag"), is attached to one terminus of the protein. As a result, when the lysate is passed over a chromatography column containing nickel, the histidine residues ligate the nickel and attach to the column while the untagged components of the lysate pass unimpeded.\n\n\n[edit] Cellular localization\n \nProteins in different cellular compartments and structures tagged with green fluorescent protein.The study of proteins in vivo is often concerned with the synthesis and localization of the protein within the cell. Although many intracellular proteins are synthesized in the cytoplasm and membrane-bound or secreted proteins in the endoplasmic reticulum, the specifics of how proteins are targeted to specific organelles or cellular structures is often unclear. A useful technique for assessing cellular localization uses genetic engineering to express in a cell a fusion protein or chimera consisting of the natural protein of interest linked to a "reporter" such as green fluorescent protein (GFP). The fused protein's position within the cell can be cleanly and efficiently visualized using microscopy, as shown in the figure opposite.\n\nThrough another genetic engineering application known as site-directed mutagenesis, researchers can alter the protein sequence and hence its structure, cellular localization, and susceptibility to regulation, which can be followed in vivo by GFP tagging or in vitro by enzyme kinetics and binding studies.\n\n\n[edit] Proteomics and bioinformatics\nMain articles: Proteomics and Bioinformatics\nThe total complement of proteins present in a cell or cell type is known as its proteome, and the study of such large-scale data sets defines the field of proteomics, named by analogy to the related field of genomics. Key experimental techniques in proteomics include protein microarrays, which allow the detection of the relative levels of a large number of proteins present in a cell, and two-hybrid screening, which allows the systematic exploration of protein-protein interactions. The total complement of biologically possible such interactions is known as the interactome. A systematic attempt to determine the structures of proteins representing every possible fold is known as structural genomics.\n\nThe large amount of genomic and proteomic data available for a variety of organisms, including the human genome, allows researchers to efficiently identify homologous proteins in distantly related organisms by sequence alignment. Sequence profiling tools can perform more speci
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because 70% can penetrate deeper into the protein tissues.\n100% coagulates the outer part of the protein only.  It does it too fast so it only reaches the outer portion not the inner layers.