Has any scientist created an organism in a laboratory using the primitive kind of Earth's environment, like the one used by Miller, etc.?
I read that protobionts (coacervates and microspheres) have been created in the lab by Alexander Oparin and Sidney Fox respectively. I also read that these were not 100 percent living.
Answer
Now the question you have is really very interesting and deep but the short answer is we still don't know enough to be able to decide
1.Precisely when an assembly of molecules and their interactions becomes a living organism and
2.We have no idea what the "alternatives" of what we know today as life are, so we can't be really sure what kinds of "other possible life forms" can be generated both in the laboratory and in the outer space on some distant planets.
In order to tackle the first question in the last decade or 2 new science has emerged-the field of synthetic biology whose goal is to "recreate" life in the laboratory from materials generally not considered to be alive-like cell membranes and DNA alone out of the cell but they are also trying to upgrade our current technology for manipulating the DNA of living organisms to the point where we can literally create new species in the laboratory. Here are some very good publications by the most renowned expert in the field of synthetic biology Craig Venter-here and here . These are seminal works for synthetic biology but if you want to know more you can search entire journals dedicated only to synthetic biology-here,here and here. There are actually hundreds of articles pertaining exactly to the answer of the question you are posing-what are the experiments we have done in the laboratory to recreate life in controlled conditions and how much we can "model" it to our own desires. Even if you only skim the abstracts of the articles in these journals you will be able to see how far we are in the de novo genesis of life and what we can do with our newest technologies to mimic the process by which the first cells arose. You would also find good work showing the prospects for manipulating current living cells to "synthesize" what scientists would consider new "man-made" species of bacteria. Although we aren't quite there yet the prospects are exciting at the least and really mind blowing at best. The discipline (I call it discipline because it isn't "just" a science but a combination of recombinant DNA technology, advances in the chemistry of large biomolecules, cutting edge genomics and proteomics, novel methods for computational modeling of metabolism and genomics and many more disciplines combined into one direction) is just in its "infancy" but even only what we can do now is enough to open the door for an entire new array of biotechnologies to come. However, I personally advise you to begin with the 2 papers of Craig Venter I already showed you and also this one and then go to these journals.
I would also recommend you seeing the reviews of Pier Luigi Luisi on the attempts of constructing self-replicating vesicles in the laboratory-here,here and here. He in my opinion is the man who has got the closest to actually achieving in the laboratory the synthesis of systems close enough to the living cell-self-replicating lipid vesicles. I think if we are ever to recreate life in the laboratory this is the closest shot we have. You might also be interested in this paper here and this here who pertain to the same field-the use of lipid vesicles as a simple way to recreate the origins of life and to build living cells in the laboratory.
Lately, there is also one brand new interesting paper from this year on the issue of creating molecules and systems of molecules capable of evolving themselves into more complex ones here.
Now on the second question-how to recognize what kinds of forms of life can exists in the universe, there is also a fast growing new science-the science of astrobiology whose goal is to devise a broader perspective on what life is. can be and how it can arise in the wide context of the cosmos. not only in the particular context it occurred here on Earth. There are 2 good journals pertaining to this field here and here which can give you very good perspective as to what the field is about and how it can shed more light both on what life generally is in the universe and how can we recreate it on Earth. I would also recommend you to read the articles Life as we don't know it, Defining life,How rare is complex life in the Milky way? and The potential of detecting "Life as we don't know it" by fractal complexity analysis. Those papers should be nice "introduction" to the world of astrobiology and if you follow through browsing the journals I just showed you can get a pretty good idea where we are today in the quest to answer your question.
You might also want to consider learning more about the origins of life. It also is a field directly related to the question you posted. Nice review on the topic is here and you can also check out this article and this article here. Then, you may want to check out the journal dedicated specially to investigation on the origins of life-Origins of life and evolution of biospheres and watch this online lecture on the subject.
Another issue pertaining to the question is the definition of life and how difficult it is to be formulated. If you become familiar with the issue you will understand why it's so difficult to tackle the problem of how to synthesize life, where it is throughout the universe and how it originated here on Earth. I recommend you these 2 seminal works on the definition of life here and here. But I would also recommend you to read this,this and this article to get a deeper look at the problems we face even defining life today. If we can't even agree on what life is how do you expect to be able to understand how it originated or how to create it?
Another direction you could also look at is our attempt to model and describe what we can call life at all levels it can appear-the field of artificial life. You can learn more about it in the journal Artificial life which deals with our attempts at modelling complexity in abstract systems close to the dynamics of the living ones. Yet another attempt at understanding the dynamics of the living is the interesting field of biosemiotics about which you can read short overview or get more accustomed into in its journal here. I think this list is more than enough to cover all the major directions your interests can take you on.
But to get "the bigger picture" of the question here you need to do much more than that and to follow virtually every publication pertaining to the definition, origin, synthesis and location of life throughout space and time and this can be daunting task, believe me, I do it every day since years! But despite the enormous quantity of papers and articles I go through there are always newer and newer things to discover and no matter how many hours I dedicate to this task and how much it fulfils me there are still gaps in my knowledge and am learning new things about different perspectives on the BIG question-What is life? all the time!
So, to give you an advice derived from personal experience-the question you tackle is really very interesting and fundamental one but even if it consumes all your time and efforts you would still not be able to follow everything which can be pertained to it, so my advice is to take only 1 or 2 approaches used in either of the fields I just described you and concentrate only on their keywords to follow the advances of the people behind them. Take something from synthetic biology, something from the origin of life field or something from astrobiology and visit the journals I just showed you from time to time to search with these keywords and see what is new. Then you would have good enough idea how close we are to synthesizing life in the laboratory and knowing more about its nature and origins. This is my long answer and the best advice I can give you.
Hope it helps :)
No comments:
Post a Comment