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7

I found article in Nature: A helper phage to improve single-chain antibody presentation in phage display Experimental protocol Standard cloning procedures, determination of colony-forming units and plaque-forming units, and immunoblot after PAGE were carried out according to Sambrook et al. Construction of the packaging cell line. ...


7

There are metabolic processes in which ATP is synthesised without the involvement of ATP synthase. The best examples are, in fact, two steps in the glycolytic pathway, catalysed by phosphoglycerate kinase and pyruvate kinase. This is why, in the absence of any aerobic metabolism, many organisms (like yeast for example) can grow quite happily, producing two ...


5

Do you know about BioPython? Here, on another website, someone already asked this question and a pretty nice answer was provided by Brad Chapman. He gives already written functions to perform this kind of analysis (I personally haven't tried the codes). In Perl there is Bio::Align::DNAStatistics. You might adapt it to Python. This might be useful as well. ...


4

If the process of evolution is driven by completely random process... It's not. The evolution of "better" protein (and other) molecules happens because of selection, a very non-random process. The repeated selection of better molecules, and then of the variants of the better molecules, repeated many times, will lead to "good" molecules (in the sense ...


3

Expanding on the comment by @Chris: Short Answer Overlapping sequences imply evolutionarily conserved regions, i.e. preserved by evolution through time due to theirs having some important function. Long Answer Assuming the sequences are homologous, overlapping regions of similarity reveal "evolutionarily conserved regions". These are regions in the ...


3

There are wikipedia pages on Geological history of oxygenation and on Great Oxygenation Event I don't know much about geology and someone else might be able to give an exhaustive list of evidence (and method of measuring) concerning the oxygen concentration on earth but that would be a very long answer I guess! Rather than a full answer, I give you a list ...


3

Yes, there are cases where one gene has become two. Or, at least, where multiple functions carried out by a single protein, the product of one gene, are carried out by distinct proteins, the products of different genes, in another species. One case I have personally worked with is the bacterial SelB protein. It is essential for selenoprotein biosynthesis ...


2

Since we only have one planet that we know of with life, it's a bit difficult to make good estimates on the probability of various events in the history of life. To make a good estimate, you'd want to have thousands of planets very similar to earth to compare. Since we don't have access to that kind of data, one proxy which you can look at is how long did ...


2

Exactly how genetic material changes from one generation to the next is a very complex subject. But essentially you are right. The change in genes from one generation to the next is not only mutations though. It is also mixing of the genes carried by the male and the genes carried by the female. The selection process is also very complex, and sexual ...


2

Human teeth are strongly attached to a socket, which is not true for many other animals. Our teeth are designed to last our lifetime (specifically up until the point we pass on our genes). Most people's teeth last until they are in their 50s, when the majority of people have passed their genes on. As for food attacking our teeth, this would be fruit juice, ...


1

Others have nicely summarized to different types of biological networks and how they can evolve. I would like to make a fine distinction between evolution and dynamic adaptation and add some comments about relative evolvabilities of different biological networks. Given an architecture, a network can respond dynamically to different inputs. The preferred ...


1

I find this a very interesting question as I personally work with networks very frequently! Based on your definition of evolving networks, it is feasible to consider protein-protein interaction networks as evolving since over time more and more interactions between different proteins are discovered and more novel proteins (nodes) are tested for their ...


1

The following does not answer the question! It only gives some ideas of where I personnaly found some work involving network analysis in biology. Most of the networks I've heard about in biology concern network of species interactions network of individual interactions within a population network of subpopulation interactions within a metapopulation ...


1

Not sure if this meets your definition of a network, but there are several kinase cascades which transmit signals. For example, the basic MAPK cascade has evolved to serve different roles via the ERK, JNK, and p38 cascades The evolution of the MAP kinase pathways: coduplication of interacting proteins leads to new signaling cascades. Caffrey et al., Journal ...


1

This would be a very long answer but just to give you some hints, the migrational mechanisms are already there and the cancerous cells makes use of them to metastasise. So in short its deregulation. What is under selection pressure tho are cancerous cells themselves to constantly change and evade cellular fail safes which kill (apoptosis) uncontrollably ...


1

Human teeth and animal teeth are not fragile. It is meant to last a life time, barring physical injury. If anything makes it fragile it is ourselves. The main two causes of tooth loss is dental decay and gum disease. Both are cause by the soft tenacious bacteria filled biofilm called 'Plaque". If there is no plaque then there is no dental caries(cavities) ...



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