Hot answers tagged biochemistry
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Here is a possible answer given by this paper:
http://www.ncbi.nlm.nih.gov/pubmed/16794952
or
http://www.math.unl.edu/~bdeng1/Papers/DengDNAreplication.pdf
It gives a Darwinian explanation to the question. It approaches the problem from Claude Shannon's theory for communication. It treats DNA replication conceptually and mathematically the same as a data ...
3
This is one of my favorite charts demonstrating the complexity of amino acid properties:
http://www.jalview.org/help/html/misc/aaproperties.html
Histidine is probably the most complicated amino acid in this regard (just compare how many circles it falls into). But don't undersell Cysteine and Methionine; those sulfurs exhibit some surprising behavior, ...
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The imidazole ring in histidine is indeed aromatic. But an aromatic amino-acid is not usually defined as "an amino-acid with an aromatic ring". Rather, they are usually defined by common chemical properties, such as high absorption at 280nm, or better their common metabolic pathway.
Histidine as a stand-alone amino-acid is a weak base, but this is mainly ...
2
The binding of proteins (and cells) to glass (or silicon) surfaces can be prevented by coating the glass with polyethylene glycol (PEG) groups. PEG-silane is a reagent used to create this coating.
PEG-silane (the image shows a methoxy- version) (image taken from here; no connection) will coat glass surfaces because the silane portion (right hand end of ...
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As Arthur Kornberg said: "Don't waste clean thinking on dirty enzymes."
Discovering an assay for a biological event in a cell-free extract opens the way to its molecular resolution and reconstitution (Commandment I). Trying to devise a mechanism with a crude extract, even with ingenious experiments, is generally a waste of effort. An extract is too ...
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There are both chemical and electrical synapses in many organisms. The electrical synapses are called gap junctions.
As you point out, the primary advantage of gap junctions is their speed, and they are commonly used in systems involving defensive reflexes.
However, as AndroidPenguin indicates, chemical synapses allow for greater computational abilities ...
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This is the coolest part. Those synapses are the reason the brain is so complex! Basically you've got the first part right, the neurones are quicker and they transmit messages from one end to the other. The other thing you have to do is analyse and calculate. Signals from multiple neurones feed into a single neurone using a chemical synapse. Similarly the ...
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The answer is no really, but some variants might allow you to study inhibition.
Michaelis Menten kinetics are experiments which try to characterize the catalysis characteristics of a reaction but to do so the numbers are obtained at concentrations of substrate that you dont find in a cell.
Vmax is defined as the maximum rate at which the reaction is run ...
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As far as I am aware there are various regulatory mechanisms (allosteric regulation, hormonal control) in place to minimise futile cycling by ensuring that phosphofructokinase (glycolysis) and fructose 1,6 bisphosphatase (gluconeogenesis) are not both active at the same time.
See this Wikipedia article for a starting point.
The precise regulation of ...
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There are various parameters that describe change of seasons such as day length, temperature, humidity. But it can be assumed that most of these parameters ultimately depend on one parameter- day length.
The response of plants towards the length of day/night cycle is called photoperiodism (which dictates spring flowering).
This article explains the effect ...
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