Tuesday 19 January 2016

"Exquisitely Designed" Enzyme Challenges Darwinian Explanations


It’s complicated, yet exquisitely designed. Image courtesy of Boghog2, public domain.




Joel Kontinen

Intelligent design is becoming increasingly obvious. So obvious that researchers are having a hard time describing genetics or biology without using the word designed.

In today’s research, Darwinese with its erroneous concepts like junk DNA seems to belong to the distant past.

A brief report issued by the Massachusetts Institute of Technology (MIT) illustrates this trend. Catherine Drennan, a professor of chemistry and biology at MIT, recently wrote a paper published in eLife with her colleagues on ribonucleotide reductase (RNR).

She describes it as being “exquisitely designed.”

The MIT report states:

Cell survival depends on having a plentiful and balanced pool of the four chemical building blocks that make up DNA — the deoxyribonucleosides deoxyadenosine, deoxyguanosine, deoxycytidine, and thymidine, often abbreviated as A, G, C, and T. However, if too many of these components pile up, or if their usual ratio is disrupted, that can be deadly for the cell.

A new study from MIT chemists sheds light on a longstanding puzzle: how a single enzyme known as ribonucleotide reductase (RNR) generates all four of these building blocks and maintains the correct balance among them
.”

While professor Drennan attempts to speculate about a plausible evolutionary origin of this enzyme, it does not work as if it were the result of Darwinian processes:

The enzyme’s active site — the region that binds the substrate — changes shape depending on which effector molecule is bound to a distant site on the enzyme. For this enzyme, the effector molecules are deoxynucleoside trisphosphates such as deoxyadenosine triphosphate (dATP) or thymidine triphosphate (TTP).”

Once again, research shows that living beings are a lot more complicated than Mr. Darwin could ever have dreamt. They’re full of coded systems and miniature machines.

Scientists will even admit that our genome is ”a complex orchestra.”

Source:

Trafton, Anne. 2016. Supply chain: Chemists discover how a single enzyme maintains a cell’s pool of DNA building blocks. MIT News (12 January).