It was Har Gobind Khorana who carried Watson and Cricks' legacy so elegantly. He was the first to synthesize oligonulceotides (short sequences of nucleotides: RNA or DNA) and the first to isolate DNA Ligase (an enzyme that 'stitches' pieces of DNA together). Now maverick Venter is poised to give the finishing touch to it.
Craig Venter, the bald and bearded American biologist, who has the habit of hitting newspaper headlines, is 'back in black'. He has now synthesized a piece of chromosome, in his laboratory. His team, headed by Nobel laureate Hamilton Smith, is now on the verge of creating the first artificial life form, christened Mycoplasma laboratorium. This 'organism', containing 381 genes, is capable of behaving as an infecting organism, when it enters a living cell.
What does it mean? A lot. For example, this could herald a new era in drug delivery systems. They can also be manipulated to manufacture weapons of bioterrorism. Even a highly infectious organism may emerge from a research misadventure.
Prion proteins (proteinaceous infective organism) are proteins, which are normally present in cells such as nerve cells. When the shape of these proteins are altered, they may behave as infecting organisms too. These 'misfolded' proteins have the ability to distort other proteins too, thus giving them abnormal shapes. These abnormally folded proteins do not work properly, and diseases such as mad cow disease (bovine spongiform encephalopathy: it makes so many holes in the brain that it resembles a sponge), Creutzfeldt Jakob disease (CJD), and many others.
So what is life? Protein molecules consisting of simple amino acids; or simple nucleotide sequences comprising of nitrogenous bases and pentose sugars? You can well imagine a strand of molecule, the physical part, but where is this abstract part called life? And more importantly, what next?
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