Potassium Channels Even More Clever Than Thought

What Was Thought to be the Problem is Actually the Solution

At the cellular level our bodies depend on a delicate balance of ions that is constantly adjusted. Potassium ions, for example, are atoms with one missing electron which are constantly streaming into or out of our cells. These positively charged ions enter and exit the cell via huge protein machines called channels which are imbedded in the cell wall and, like a donut, have a hole in the middle through which the ions flow. What is astonishing is how well these channels work. Not only do they open and close as needed, but they have two seemingly impossible design features. On the one hand they are extremely selective, allowing only a particular type of ion to flow through it. But on the other hand, they allow the chosen ions to flow through incredibly fast. It would seem that high selectivity would come at the cost of a slow transmission rate. But no, potassium channels for instance filter out practically everything but potassium ions, and yet their flow rate is practically at the maximum speed that is physically attainable. Now a recent study has added more information about how potassium channels perform their amazing feats.

One of the conundrums with ion channels is how ions of like charge, which therefore repulse each other, could be stuffed through the small hole in the ion channel protein machine. One possible answer is that the ions are separated from each other. For more than a decade now it has been thought that the potassium ions flowing through potassium channels are separated by water molecules. This would avoid the problem that the positively charged potassium ions repel each other, not making for a very smooth or concentrated flow.

The new study, however, persuasively argues that, in fact, the potassium ions travel together, not separated by water molecules. This higher concentration of potassium ions is achieved with a subtle, complex design of the charge contour within the channel. In fact, as the paper explains, the �repulsion between adjacent ions is found to be the key to high-efficiency K+ conduction.�

That's incredible, and this poses a problem for the theory of evolution because it means that random mutations, rather than forming a gene that produces some simple, easily formed molecular donut, instead must have discovered an astronomically unlikely design. Final causes and teleology which are so much despised by evolutionists are clearly the better explanation for the potassium channel. No that doesn�t mean science comes to an end, no that is not a religious explanation, and no that isn�t the final word in the matter. That is just what the science is telling us, loud and clear.