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DNA holds genetic information and holds the key to the evolution of living organisms. Transcription and translation mechanisms enable living cells to process information encoded in DNA. To that end, transcription and translation are fundamental mechanisms needed to enable the evolution of organisms. Molecular machines (enzymes) carry out these mechanisms by reading the information in DNA and using it to construct proteins.
Did the first living cell contain the machinery needed for translation and transcription? or Did they evolve over time?
EDIT: Edited the question to narrow the scope.
The main hypothesis is that all starts from RNA. "The RNA world". There was no DNA and no proteins. Both function was performed by RNA. Now there are no living organism that carrying information in RNA (only viruses… ), but there is "enzymes" from RNA - ribozymes.
The evolution to DNA was later, according to this hypothesis.
There is really good article in wiki.
or if you want something more look here
From our knowledge of present-day organisms and the molecules they contain, it seems likely that the development of the directly autocatalytic mechanisms fundamental to living systems began with the evolution of families of molecules that could catalyze their own replication. With time, a family of cooperating RNA catalysts probably developed the ability to direct synthesis of polypeptides. DNA is likely to have been a late addition: as the accumulation of additional protein catalysts allowed more efficient and complex cells to evolve, the DNA double helix replaced RNA as a more stable molecule for storing the increased amounts of genetic information required by such cells.
The History of PCR
Making the Pursuit Possible
Unfortunately, talk is cheap. What stopped Turing from getting to work right then and there? First, computers needed to fundamentally change. Before 1949 computers lacked a key prerequisite for intelligence: they couldn’t store commands, only execute them. In other words, computers could be told what to do but couldn’t remember what they did. Second, computing was extremely expensive. In the early 1950s, the cost of leasing a computer ran up to $200,000 a month. Only prestigious universities and big technology companies could afford to dillydally in these uncharted waters. A proof of concept as well as advocacy from high profile people were needed to persuade funding sources that machine intelligence was worth pursuing.
2. The Imaginative Pioneers of Nanotechnology
The American physicist and Nobel Prize laureate Richard Feynman introduce the concept of nanotechnology in 1959. During the annual meeting of the American Physical Society, Feynman presented a lecture entitled “There’s Plenty of Room at the Bottom” at the California Institute of Technology (Caltech). In this lecture, Feynman made the hypothesis “Why can’t we write the entire 24 volumes of the Encyclopedia Britannica on the head of a pin?”, and described a vision of using machines to construct smaller machines and down to the molecular level . This new idea demonstrated that Feynman’s hypotheses have been proven correct, and for these reasons, he is considered the father of modern nanotechnology. After fifteen years, Norio Taniguchi, a Japanese scientist was the first to use and define the term “nanotechnology” in 1974 as: “nanotechnology mainly consists of the processing of separation, consolidation, and deformation of materials by one atom or one molecule” .
After Feynman had discovered this new field of research catching the interest of many scientists, two approaches have been developed describing the different possibilities for the synthesis of nanostructures. These manufacturing approaches fall under two categories: top-down and bottom-up, which differ in degrees of quality, speed and cost.
The top-down approach is essentially the breaking down of bulk material to get nano-sized particles. This can be achieved by using advanced techniques such as precision engineering and lithography which have been developed and optimized by industry during recent decades. Precision engineering supports the majority of the micro-electronics industry during the entire production process, and the high performance can be achieved through the use of a combination of improvements. These include the use of advanced nanostructure based on diamond or cubic boron nitride and sensors for size control, combined with numerical control and advanced servo-drive technologies. Lithography involves the patterning of a surface through exposure to light, ions or electrons, and the deposition of material on to that surface to produce the desired material .
The bottom-up approach refers to the build-up of nanostructures from the bottom: atom-by-atom or molecule-by-molecule by physical and chemical methods which are in a nanoscale range (1 nm to 100 nm) using controlled manipulation of self-assembly of atoms and molecules. Chemical synthesis is a method of producing rough materials which can be used either directly in product in their bulk disordered form, or as the building blocks of more advanced ordered materials. Self-assembly is a bottom-up approach in which atoms or molecules organize themselves into ordered nanostructures by chemical-physical interactions between them. Positional assembly is the only technique in which single atoms, molecules or cluster can be positioned freely one-by-one .
The general concept of top down and bottom up and different methods adopted to synthesized nanoparticles by using these techniques are summarized in Figure 2 . In 1986, K. Eric Drexler published the first book on nanotechnology 𠇎ngines of Creation: The Coming Era of Nanotechnology”, which led to the theory of “molecular engineering” becoming more popular . Drexler described the build-up of complex machines from individual atoms, which can independently manipulate molecules and atoms and thereby produces self-assembly nanotructures. Later on, in 1991, Drexler, Peterson and Pergamit published another book entitled “Unbounding the Future: the Nanotechnology Revolution” in which they use the terms “nanobots” or 𠇊ssemblers” for nano processes in medicine applications and then the famous term “nanomedicine” was used for the first time after that .
The concept of top down and bottom up technology: different methods for nanoparticle synthesis.
The origin of molecular machines - Biology
The Institute of Molecular Biology -- the IMB -- is a group of biologists, chemists, and physicists at the University of Oregon who have pooled their expertise to tackle fundamental questions in molecular biology. What are the underlying principles that define life? How do organisms develop and respond to their environments in an organized fashion? How does life evolve? How can we translate our molecular understanding into novel therapies?
To address these questions, the IMB boasts a highly collaborative faculty with expertise in genomics, cell biology, biochemistry/biophysics, systems biology, microbiology, and evolutionary biology. Our researchers use a wide variety of biological systems, from germ-free zebrafish to in vitro-reconstituted molecular machines to computational models. As a result, students enrolled in our PhD program come away with the broad conceptual and technical skills necessary to succeed in modern biological research. Further, our state-of-the-art facilities and excellent support staff allow members of the IMB community to focus their efforts on science.
The Institute of Molecular Biology strives to create an inclusive and welcoming environment to scientists of all racial, ethnic, socioeconomic and other backgrounds. Systemic, even murderous, racism has resulted in centuries-old barriers to Black scientists in particular. We are committed to the difficult work of tearing down these barriers. IMB leadership fully acknowledges that our past, present and future role as gatekeepers to science places the responsibility on us to work toward correcting these inequities. We also recognize our success depends on engaging with and learning from faculty, staff, trainees and the broader community to design and implement genuine solutions. We invite you to share your thoughts and join us in confronting racism and bias. Together, we will cultivate an institute that nurtures diversity to improve society while enabling bolder and more creative science.
The origin of molecular machines - Biology
A long path leads from the origins of primitive "life," which existed at least 3.5 billion years ago, to the profusion and diversity of life that exists today. This path is best understood as a product of evolution.
Contrary to popular opinion, neither the term nor the idea of biological evolution began with Charles Darwin and his foremost work, On the Origin of Species by Means of Natural Selection (1859). Many scholars from the ancient Greek philosophers on had inferred that similar species were descended from a common ancestor. The word "evolution" first appeared in the English language in 1647 in a nonbiological connection, and it became widely used in English for all sorts of progressions from simpler beginnings. The term Darwin most often used to refer to biological evolution was "descent with modification," which remains a good brief definition of the process today.
|Life Form||Millions of Years Since |
First Known Appearance
|Microbial (procaryotic cells)||3,500|
|Complex (eucaryotic cells)||2,000|
|First multicellular animals||670|
|Vertebrates (simple fishes)||490|
|Australopithecine ancestors of humans||4|
|Modern humans||0||.15 (150,000 years)|
So many intermediate forms have been discovered between fish and amphibians, between amphibians and reptiles, between reptiles and mammals, and along the primate lines of descent that it often is difficult to identify categorically when the transition occurs from one to another particular species. Actually, nearly all fossils can be regarded as intermediates in some sense they are life forms that come between the forms that preceded them and those that followed.
The fossil record thus provides consistent evidence of systematic change through time--of descent with modification. From this huge body of evidence, it can be predicted that no reversals will be found in future paleontological studies. That is, amphibians will not appear before fishes, nor mammals before reptiles, and no complex life will occur in the geological record before the oldest eucaryotic cells. This prediction has been upheld by the evidence that has accumulated until now: no reversals have been found.