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First off, the difference between the types of inhibition: competitive inhibition: The inhibitor only binds to the substrate-free form of the enzyme. (Not necessarily at the active site!) uncompetitive inhibition: The inhibitor only binds to the substrate-bound form of the enzyme. noncompetitive inhibition: The inhibitor binds equally well to both the ...


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After several hours of 'work', the neuro-transmitters are depleted of what they need for good cognitive function. What they need is quality food which most of us don't eat enough of. Synapses are slower to exchange neurons. Basically, lack of active neurotransmitters is the reason for most people who are otherwise healthy. It's not the same mechanism as ...


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It depends on how much time elapsed between adding the concentrated antibodies to the diluting solution and adding the diluted antibodies to the slide. If it was just a couple of seconds, then I can abolutely see there being a difference. Even if it was longer - say 30-90 seconds, even - there potentially could be antibody gradients in the solution without ...


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No. Your supposition is incorrect — the phosphate in glyceraldehyde 3-phosphate has to come from somewhere, and it comes from glucose 6-phosphate. The reason a second ATP is required before you get to the triose phosphate stage in glycolysis is that you are generating two molecules of triose phosphate. In the pentose phosphate pathway (energy-producing non-...


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Only about 5–6% of triglyceride (fat) can be converted to glucose in humans. This is because triglyceride is made up of one 3-carbon glycerol molecule and three 16- or 18-carbon fatty acids. The glycerol (3/51-to-57 = 5.2–5.9%) can be converted to glucose in the liver by gluconeogenesis (after conversion to dihydroxyacetone phosphate). The fatty acid ...


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Most reactions require an activation energy to cross an energy barrier (this you may already know) after which the reaction is downhill. Even though enzyme catalysed reactions have a relatively lower activation energy compared to that of an uncatalysed reaction, there is still a transition state that has a higher free energy compared to the products. This ...


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2-mercaptoethanol (2ME) reduces the disulphide bonds in proteins. If disulphide bonds are connecting two polypeptide chains ("intermolecular") then 2ME would cause them to separate and therefore instead of a higher molecular weight (MW) band you would get one or more lower MW bands. However, if there are disulphide bonds in the same polypeptide chain, they ...


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In the biological context, membrane-partitioning is usually referring to the stage in which the transmembrane-destined region of a protein moves from interacting with the water, to interact with the interface of the membrane. In the diagram below showing a four step thermodynamic cycle, the partitioning free energy can be referred to as as ΔGwiu in terms ...


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It seems that beta-glucosidases do not require co-factors but some alpha-glucosidases are co-factor dependent. Some bacterial alpha-glucosidases (GH4 family) require NAD+ to function (Hall et al., 2009). Thermotoga maritama alpha-glucosidase (GH4 family) requires Mn2+, in addition to NAD+ to function (Lodge et al., 2003). Ferroplasma acidophilum alpha-...


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Apparently not for lactase and β-galactosidase, as one might expect for this sort of hydrolytic reaction. There are also Wikipedia entries for maltase, sucrase and trehalase with references you can follow up to check yourself.


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The mechanical stability of a protein (I am assuming by strength you mean mechanical stability) depends greatly on the general context and there is no clear connection between alpha helix or beta-sheet content and stability. For example fibroin, one of the main components of spider silk and one of the strongest proteins known, consists mainly of beta sheets ...


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An SDS-PAGE standard curve of Rf vs LogMW is linear because the standard you're given is engineered to behave that way. An expanded SDS-PAGE curve would show that the actual graph is sigmoidal: Structues that are too large can't enter the matrix, and too small they pass right through. Your standard has taken into account the % composing the gel, and the size ...


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Some more hours of literature research finally produced a result: As published by Khan et al. 2006 6x-His-tag has an association constant of kon = 6.3 10-3 and a dissociation constant koff = 1.8 10-3.


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Your description of it is largely correct, but the electron transport chain does not simply "dump" charged oxygen ions in the mitochondrial matrix. Instead, cytochrome C oxidase (complex IV) binds the O$_2$ molecule to one of its heme groups, and the reduction O$_2$ + 4 H$^+$ + 4 e$^-$ $\rightarrow$ 2 H$_2$O occurs at the heme group before water is released. ...


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Membrane potential (ΔµH) AKA the membrane electrochemical potential, may be thought of as the voltage that is experienced across the membrane, analogous to a battery. The extracellular side is typically positive, while the cytoplasmic side is typically negative. This induces the electrochemical gradient with ions having a preference for a particular side ...


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A motif means a pattern. Since nucleotides and proteins have a sequence, they can have some patterns of sub-sequence that may serve some kind of function. For example TATA box in DNA serves as a promoter element. Similarly proteins can have some sequence motifs that can serve as recognition sites for binding partners (amongst other functions). Similarly ...


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They are doing a peptide competition assay (see abcam protocol). The antibody is incubated with a purified sample of the antigen and used in a normal Western-Blot of cell lysates. Any cross-reactivities of the antibody would still be visible as only the interaction with the epitope of interest is blocked. So all bands that disappear after such treatment are ...


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Ferredoxins and variants such as fladidoxins and rubredoxins are simply electron carrying protein that need to be regenerated, like the more energetic NADPH. The key thing to remember is that redox balance is key. You cannot have electron pair accumulate so there has to be a terminal acceptor. In the case of aerobic resipration it is oxygen, in the case of ...


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The terms are different. Oxidation number is the difference in number of electrons (not pairs) from the elemental form (which for many elements exists only on paper) of an atom. Degree of reduction is a more uncommon term that is basically the number of electrons that atoms in a molecule are donating per atoms of a given element. It is calculated formally by ...


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As you suspected, hemoglobin is the reason why O$_2$ and CO$_2$ in blood are expressed as a pressure (mmHg) and not a concentration. Most of the oxygen in blood is bound to hemoglobin; the concentration of free oxygen in plasma is low because oxygen does not dissolve well in water (which is of course the reason why hemoglobin exists in the first place). ...


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By the ideal gas law, PV = nRT, you can find pressure by dividing both sides by volume, P = nRT/V. Since R is a constant, and you can usually assume T isn't changing very quickly for biological systems, you can pretend P = n/V, which is moles per unit volume, analogous to concentration. The reason the units are written in pressure is probably because gases ...


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What should be the correct reason for bilayer arrangement? I'll answer your second question first, but there is an almost identical question on this site already: Why do cells have a bilayer? There is water on the extracellular and intracellular side of the membrane. What's actually happening at a molecular dynamics level is the self-association of the ...


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One way of examining this is by looking at the transcriptome as a whole before and after the introduction of the chemical. I would use microarray or next generation sequencing RNA-seq technology to look on the expression level of all the genes after the introduction of the chemical, some inert control and no treatment control. Then, you can calculate the ...


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To rephrase what you already mentioned in your question: For a KEGG Module to be completed (so that an organism can perform a certain function) you need a certain set of functional units or enzymes. So to evaluate the abilities of an organism you would check its genome for the gene sequences related to the module by performing the logical operation you ...



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