Complexity of Life

The other day I was listening to some microbiology classes via podcast that I got from iTunes U.

They were talking proteins, their structure and how they fold into compact shapes. Scientists used to study x-ray crystallography of proteins to understand their physical and chemical structure and now they don't look directly at proteins any more. They look at the DNA to figure out what kind of protein is made. The way this works is that DNA transcribes, or writes RNA or proteins, and RNA transcribes proteins. You've probably heard about how DNA is both a structure and a code. When you unravel DNA, it makes a template to produce all kinds of chemicals. This is called transcription.

Our technological advance, abandoning an old technique because of new knowledge makes me wonder if we might be missing something. What if transcription "shudders" and does not make a protein corresponding to the exact DNA sequence? It's possible that transcription is more complex than making a copy of a fragment of a gene, it could be that there is a cut and paste sequence in there somewhere. By only using DNA sequencing, are we sometimes misunderstanding protein sequence and shape?

If the DNA in a single cell in your body was unraveled, it would be 2 meters long. And only a few atoms across. This structure folds back on itself in an intricate way to fit into the nucleus of a cell. The were talking about primary, secondary, tertiary, and quatranary folds of proteins, and DNA has similar folds and it's called supercoiling.

Genetic Microbiologists already know about "chaperones". These are auxiliary chemical that help proteins fold properly. They are like little chemical jigs that hold or twist a protein while more chemicals are being added to the end of the protein chain. Partly because they need this special assistance, the complexity is enormous. Proteins, which consist of 50 to 100 base amino acids don't work properly if they are not folded properly. Prions, responsible for mad cow disease in cattle, Creutzfeldt-Jakob disease in humans, and chronic wasting in deer, are no more than a misfolded protein. One little error and the whole protein transforms from a useful building block to a deadly toxin.

We are still, in some ways, in the early phases of understanding all the complex machinations of the chemicals of life. Many discoveries in science are made by fortuitous accidents. By the same token, how many missteps have led us astray? How many times has "something better" come along and caused us to abandon a line of research? The tree of knowledge is sometimes just that, a growing and branching of direction build on past achievements. It makes you wonder if why have not missed magic or ESP or some other whole branch of untapped science because our history lead us away from that field.

You can't miss what you never had, but you can go back and look at some of the things that weren't tried, and in light of future knowledge, see if there were treasures to be had along the paths not taken.