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According to wikipedia: HIV protease inhibitors are peptide-like chemicals that competitively inhibit the action of the virus aspartyl protease. These drugs prevent proteolytic cleavage of HIV Gag and Pol polyproteins that include essential structural and enzymatic components of the virus. This prevents the conversion of HIV particles into their ...


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Your answer is correct. HIV-1 encodes a single homodimeric aspartic protease, with each monomer containing the classic Asp-Thr-Gly motif, and the dimer's active site being formed with the two monomeric active sites creating a cleft where the proteolysis takes place. In it, water acts as a nucleophile in conjunction with the aspartic acid residue to hydrolyze ...


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Enzymes usualy have a relative narrow temperature optimum, for those of our body this is usually around 37°C. It is around 37,2°C in the morning and goes slightly up to 37,7°C in the evening (see reference 1 for details). The temparature optimum for most enzymes looks somewhat like displayed in the figure (from here, interesting to read): Enzymes are ...


0

As far as I know fats are solid lipids while oils are liquid lipids in (I guess) room temperature. So saturated triglycerides are usually fats, and unsaturated triglycerides are usually oils. This is because saturated and trans-unsaturated fatty acid chains are linear while cis-unsaturated fatty acid chains are curly (non-linear). Forces between linear ...


1

If there is passive transport for each ion, then every ion will diffuse over the membrane until the concentrations will be the same, and the membrane potential will be zero. So there is active transport in the cell, which maintains the resting potential which is -63mV. So with the current concentrations the membrane potential will differ from this -63mV, ...


1

This is an important topic in immunology, especially for vaccine development. MHC or HLA is a molecule expressed by some cells of the immune system which acts like a "catcher's mitt" and "presents" short snippets of protein to other immune cells. Other molecules act alongside MHC to provide co-signals which promote or suppress immune attack against the ...


2

DNA polymerase must catalyse the addition of 4 different nucleotides to the growing strand. This means that it cannot directly determine which base to incorporate at a specific point (how would it 'know' which base to incorporate and how it would it change its specificity for different bases). This means that the specificity for which base pair to ...


3

Are you taking in an in vitro context for preventing protein denaturation after protein isolation from for example E. coli or are you more worried about proteins in the context of the whole cell? I'm no expert in the protein folding/conformation studies but from laboratory based prospective if you want to achieve denaturation for experimental purposes, you ...


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High-fidelity DNA polymerases have several safeguards to protect against both making and propagating mistakes while copying DNA. Such enzymes have a significant binding preference for the correct versus the incorrect nucleoside triphosphate during polymerization. If an incorrect nucleotide does bind in the polymerase active site, incorporation is slowed ...


3

Really the question how does protein folding work? But let me answer your questions... 1) Very few proteins have disulfide bonds (usually secreted proteins) or really any covalent bond stabilizing the amino acid chain beyond the bonds that make up the polypeptide itself. Denaturation is only reversible in relatively few cases in fact. A few proteins, ...


0

Lehninger Principles of Biochemistry by Nelson and Cox is quite popular and covers everything you listed in great detail except for immunology. I don't really have a recommendation for an immunology book; I think pretty well any of them will cover immunoglobulins (they're pretty integral). My university uses Kuby Immunology by Kindt et al. Molecular ...


2

Afaik you can describe the potentials between the two sides of the cell membrane using the Nernst-equation. Yepp wikipedia writes the same here. Membrane potential is a very important thing, because human cells require stable internal concentrations of Na+, K+, Ca2+, etc... in order to work properly. These concentration can depend on species, for example ...


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This is a draft. How do the pharmacodynamics of the NSAIDs differ - -? Merck's manual ch. 36 to start little bit at an introductory level: The anti-inflammatory activity of the NSAIDs is mediated chiefly through inhibition of biosynthesis of prostaglandins (Figure 36–2). Various NSAIDs have additional possible mechanisms of action, including ...


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The answer here lies in epidemiology and the pathogenic nature of the virus. Humans infected with Ebola have a range of recovery rates of 5-75%, meaning that most of those infected will not survive infection. Given the combination of preparedness factors at first recognizing a true outbreak in Ebola and viral load which had already been spread by the point ...


3

coconut oil is composed mainly of medium-chain triglycerides, 1)it is smaller than other long-chain triglycerides so that it can be digested easily, 2)the digestion of coconut oil does not involve in the Pancreatic digestive enzyme system, 3) liver prefer use medium-chain triglycerides as the fuel sources 4) medium-chain triglycerides will convert to ...


0

Just to clear out some things: As stateted above, NADH is produced in catabolic reactions and is later used in the electron transport chain to obtain energy by converting NADH back to NAD+. NADPH is primarily produced in the oxidative part of the pentose phosphate pathway. NADPH is used in a) anabolic syntheses to produce cholesterol, fatty acids, ...


3

Fats include free fatty acids and their compounds with glycerol: mono-, di- and triglycerides. In a cooking context, fats refer to solid fats, and oils to fats that are liquid at room temperature. Most of them contain triglycerides. Fats belong to a broader group--lipids--, which are substances that are usually not soluble in water and usually soluble in ...


4

In principle, Meiosis is only the process in which the haploid egg or sperm are generated. Have a look at this figure, which shows Meiosis I and II (from the Wikipedia): During Meiosis I homologous recombination between homologous chromosomes can happen, the chromosomes are then distributed normally among the daughter cells. In Meiosis II the cells split ...


-1

Question: Why can't we just take enough pills to obtain these vitamins and minerals? My reasoning: There are about 45 essential nutrients, which you need to consume to be healthy and live. You can get all of them from food without thinking about them. I'm not sure if currently there are a lot of supplements on the market that contain all essential ...


3

Embalming solutions for cadaver study differ from institution to institution (and are reportedly somewhat different from embalming for funerals, but I'm not sure of those details). Typically embalming solutions for cadavers meant to be stored indefinitely consist mostly of water with lesser but roughly equal amounts alcohol (usually methanol), gylcerin, ...


0

There are multicellular organism which do not actively eat other organisms, however, there are no organisms period who do not kill other organisms. Trees, and other vertical plants, evolved in the first place in competition for sunlight. For plants, being in the shade is like smother or starving a human since they literally use sunlight to create and ...


1

Patch clamping Or Ultracentrifugation to get soluble fractions. If you get enough of it and u have validated its purity you could runs conductivity probe into your fraction


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Yes, plants! Plants are autotrophs. While Animals and fungi are heterotrophs. Have a look to the wikipedia articles. In short, autotrophs organisms are organisms that synthesize their own compounds from inorganic compounds. Heterotrophs organisms are organisms that synthesize their own compounds from organic compounds. Therefore, any multicellular plants ...


3

Yes, this is the effect of metabolizing ethanol and also the reason why excess amount of ethanol can lead to hypoglycemia. Ethanol is oxidized by the alcohol dehydrogenase to acete aldehyde. This reaction needs consumes one molecule of NAD+ per molecule ethanol oxidized: Ethanol + NAD+ <=> Acetaldehyde + NADH + H+ Acetaldehyde is oxidized by the ...


1

The fundamental principle behind this is a "sensor" or the excitation-contraction coupling, regardless where you are. Let's consider the striated muscle and the cardiac muscle. The function of excitation-contraction coupling in skeletal muscle is as voltage sensor to tell the SR, "We have got an action potential; release Ca2+ for contraction". This is a ...


4

Your cells produce thymidine by converting uridine using an enzyme called Thymidylate Synthase. 5-Fluorouracil irreversibly inhibits this enzyme. Here is the structure of 5-Fluorouracil: Here is the mechanism the enzyme uses to make thymidine: It looks like the enzyme forms a bond to the uridine ring through a sulfur. 5-Fluorouracil probably inhibits ...


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See this paper. They have studied RBP-protected sites in the entire human transcriptome by RNA-protein crosslinking followed by RNAse digestion and sequencing: PIPseq. Figure 1 of the paper shows distribution of protein protected sites in RNAs. They also correlate it with different regions of mRNA and its expression. They show number of protein protected ...


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The sRNA mediated regulation in bacteria operates via diverse mechanisms. This case of sRNA competing with a mRNA for a protein is a passive kind of regulation. This might be good for finetuning but may not be very efficient. It is much better to actively regulate a mRNA by direct binding. Also, it will work only if the concerned protein is in limiting ...


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PSI-BLAST is an iterative algorithm. Each cycle it uses a model (the position-specific scoring matrix, or PSSM) to search for sequences matching the model, next updates the model with the sequences found, and then runs the search again with the updated model. That P-value controls which of the sequences found in each iteration should be included in the new ...


3

Anti-oxidants affect human metabolism by altering the redox states of the cell and redox-regulated functions and signaling mechanisms. The following quotes are from The Redox Stress Hypothesis of Aging (Free Radic Biol Med. Feb 2012) More recently, in a major conceptual shift, ROS have been found to be physiologically vital for signal transduction, ...


2

From doing a bit of research, I quote The various analytes have different stability in serum. Serum TLI and PLI are stable for up to 2 weeks at room temperature. However, serum folate shows limited stability at room temperature. Therefore, serum samples for folate analysis should be kept at 4ºC for not longer than 48 hours, but freezing is ...


1

I would say theoretically yes, if you know lots of other information, but practically no, because of all the unknowns. According to this paper cysteine content and therefore sulfur content of proteins vary depending on what kind of organism your organic material is coming from. Animals have more, bacteria tend to have less. The sulfur content as a fraction ...


3

After some research, I could primarily find two tests for testing the protein content in dog urine. 1) The Urinalysis dipstick test (reference) which has a chance of giving false positive results (reference). Here is the link to a lab test done using the dipstick method and the results that the researchers got. A sample Dipstick (reference) 2) The ...



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