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17

I will try to answer the question in the title: how can we know the sites where DNA binding proteins bind? I'll explain two experimental methods to identify binding sites on DNA. DNase footprinting ChIP-seq (Chromatin Immuno-Precipitation with sequencing) DNase footprinting We can locate proteins bound to DNA by their ability to protect DNA from some ...


12

Some that just come to mind, in random order: One cannot skip reading: Richard Dawkins - The selfish gene And, obviously: Charles Darwin - The Origin of Species And, for those interested in the evolution of the brain (and its quirks): David J Linden - The Accidental Mind Oliver Sacks - The Man Who Mistook His Wife for a Hat Not very DNA/...


11

No, not all enzymes (or other proteins for that matter) can be obtained in functional form by recombinant expression with today's methods. As you suspect, problems arise when complex post-translational modifications are necessary to obtain the correct function. Direct modifications to peptide is one potential problem. Some of these can be resolved by ...


7

A good recollection of the early days of micro and molecular biology is "The Eighth day of Creation" It covers the early use of e. coli, the discovery of phage, transcriptional elements and the impact that DNA structure had. It's very comprehensive and really useful if you are doing molecular biology today.


7

ATryn is a human antithrombin produced in the milk of transgenic goats by GTC Biotherapeutics. It has FDA approval and I believe that it is available for prescription in the USA. Added later, after the emphasis of the question changed somewhat. Proteins produced in a mammalian system are more likely to have post-translational modifications that are much ...


7

Short answer All of your sources are correct as they are not mutually exclusive. PCR is used to isolate and amplify DNA to yield small quantities of pure target product. Gene cloning can subsequently be applied to scale the production of the fragment up. PCR thus can be part of the DNA cloning process. Background Cloning in general simply means duplicating....


7

GFP has a lot of advantages: The detection of the fluorescence works directly and doesn't need a lysis step or the uptake of a reagent. Fluorescence can be detected directly using a fluorescence or confokal microscope with the cells. This can be done while growing them on plates (works for bacteria and eukaryotic cell culture). You can sort labelled cells ...


7

Often artificial neurons are created with conventions that zero is "rest" and 1 is "threshold". The unit starts at 0, and when it reaches 1 it will send an input to all of its targets and be reset back to 0. This isn't exactly how real biological neurons work, but its a reasonable approximation in some contexts (and can do real world computations). Most of ...


6

In theory it's possible to have an approximation, but not to know with certainty. Identical twins have the same genomes and look very much alike. Whether it can be done in practice depends on how well we can model the relationship between genes and looks and on how much information is necessary for a judge to permit arresting and questioning a suspect. ...


6

You'd think if such devices were used in humans, they wouldn't require a change of lifestyle. They don't say the power always decreases over time: Katz’s snails, for example, produced up to 7.45 microwatts, but after 45 minutes, that power had decreased by 80%. To draw continuous power, Katz’s team had to ramp down the power they extracted to 0.16 ...


6

The rationale for the choice of higher organisms as the producing source is based on costs and biological activity. Biological activity. In their active forms, various proteins have post-translational modifications (i.e. glycosylation) which are difficult to reproduce in bacteria. Alan's answer is already exhaustive. Costs. Mammalian cell lines are easier ...


6

This is a very interesting question and I had not thought about it before. I am reiterating the background of your question. Background Cas9 cuts the both the strands of the target DNA at the same location thereby making a blunt end cut. Usually sticky ends and microhomologous ends lead to indels because of exonucleolytic clipping and addition of extra ...


5

Yes, bacteria will produce human (or any organism's) proteins if you introduce their genetic material but there are a few things to consider. First, the introns must be removed from the human genetic sequence. Bacteria do not have the machinery to splice out introns after transcription. This is typically done by using a viral protein to reverse transcribe ...


5

It doesn't have very many reviews, but The Epic History of Biology sounds like it's perfect. Flipping through the first chapter in the preview, it doesn't seem overly technical in any way, so secondary school-level knowledge is probably enough. If your associates have absolutely no biology experience, perhaps a run through a popular press book would ...


5

This article gives an excellent review on yogurt manufacturing, but to summarize: -Raw milk goes through centrifugation to remove somatic cells and other solid impurities. -Thermalization is conducted at "60–69 °C for 20–30 s, aiming at the killing of many vegetative microorganisms and the partial inactivation of some enzymes." After this point, the milk ...


5

Biotechnology is a gigantic field. You should have a look at the wikipedia entry for biotechnology. Because of the size of the field "biotechnology", because the word biotechnology accept different definitions and because the word interesting is extremely arbitrary it is pretty much impossible to give a good answer to this question. I am using below ...


5

I think one of the orginal reasons for using biolistic on plant cells was that it seemed to be the only method which proved to be effective. This is due to some reasons: A wide range of highly successful methodes for prokaryotic cells (calcium chlorid method, electroporation) The plant cell has in comparison to animal cells a additional layer (= cell wall)...


5

Edited after clarifications in question, Let's start with normal functions of both enzymes. Helicases separates DNA strands while polymerase synthesize DNA strands as shown in the following figure. (Image Source: Wikimedia Commons) Watch this animation, it will clear your doubts about function. However, RNA polymerase does have both activities. In cells, ...


5

One reason a Western blot is more specific than an ELISA - even one using the same set of antibodies - is background. Antibody-linked colorimetric reactions aren't completely on/off. There's always some background reaction. The antibodies are a little bit cross reactive, or non-specifically sticky, or the colorimetric coupling enzymes aren't completely ...


5

I will assume that by "identical twin", you refer to "clones". Individuals who share the same genetics but of course do not necessarily share the same womb. I won't pay much attention in detail epigenetic modification nor in the length of telomeres. While it has never been done for ethical reasons, we would probably be quite able to make a clone of a human ...


4

A fantastic book that covers the evolution of modern science since the Renaissance (including a great deal of biology) is The Scientists by John Gribbin. I found that by focusing on the people doing the science in the context of the society in which they lived, I got a much better understanding for why early scientists thought the way they did and researched ...


4

Total solids (TS): The part of the sludge that remain after drying at 105$^{\circ}$C for 20 hours: $$ TS(\%) = \frac{\textrm{weight dried at } 105^{\circ}C}{\textrm{wet weight} }\times 100 $$ Volatile solids (VS): The part of the sludge that is combusted at 550$^{\circ}$C after 2 hours: $$ VS(\% \textrm{ of TS}) = \frac{\textrm{dried weight at }105^{\circ}...


4

Would this application in humans require that a patient eats more and "breathes more" than average? From the cellular standview, each glucose and O2 molecule that you substract to the cell for use in a second futile cycle, should be replaced. However, I doubt that the amount of glucose/O2 required per hour will be so important to require additional food ...


4

According to this article, a single lacI gene copy gives rise to about 10 copies of lacI protein per cell, and we can conclude, therefore, that this is the amount required to keep a single lac operon repressed. The article also mentions the lacIQ mutation in the promoter of lacI that results in a ten-fold increase in the level of lacI protein. If a lac ...


4

NAD+ is important in this step, since it is co-factor for the glyceraldehyde-3-phosphate dehydrogenase (G3PDH), which acts as a acceptor for the hydrogen atom from the C1 (see below). If you look at the reaction, the aldehyde from the C1 is oxidized to a carboxylic acid which in a second step is turned into a phosphoester. To do so, a cysteine from the ...


4

I have had good experience using a lithium boric acid buffer from Faster Better Media. I use it for RNA gels, but it's advertised for DNA gels. I don't think it can do protein, but I've never tried it. I'm not an electrician, but higher conductivity may be the opposite of what you want. The lithium boric acid buffer claims to have less conductivity than a ...


4

The question which buffer for DNA is better is quite old. Both have their pros and cons and I list a few of them: TBE is a better conductor and is thus less prone for overheating the gel Borate is a powerful enzyme inhibitor, so if you want to apply enzymatic steps downstream, TAE is the better choice TAE gives a better resolution for large fragments TBE ...


4

Grossly, it does not matter what buffer you use. It is the pH that matters. For DNA electrophoresis EDTA is added in order to chelate divalent cations that serve as cofactors for nucleases. Tris is the base of the buffer and is used to set pH. Along with Tris one can use Boric acid, Acetic acid or phosphoric acid for adjusting the pH. The buffering range ...


4

There are already many great answers to your question, however I thought I put my comments in form of an answer. The standard for DNA agarose gel is TAE and for the protein, it depends on the size of the protein and the gel type used! Some times MOPS works best and sometimes Tris-acetate works best. It really depends on the gel used and also the protein and ...


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