The bacterial flagellum is a major icon of the modern intelligent design movement with it’s design resembling man-made machines. In this latest study, it’s molecular rotary motor reveals even more specialized complexity by repairing parts of its rotor while it is rotating! The stator was a surprise that it could be replaced during operation, even more so was the rotor…
Oxford scientists explain the new discovery in PNAS…
“Most biological processes are performed by multiprotein complexes. Traditionally described as static entities, evidence is now emerging that their components can be highly dynamic, exchanging constantly with cellular pools…. It is powered by transmembrane ion flux through a ring of stator complexes that push on a central rotor.”
“The Escherichia coli motor switches direction stochastically in response to binding of the response regulator CheY to the rotor switch component FliM. Much is known of the static motor structure, but we are just beginning to understand the dynamics of its individual components.”
“We show that the ~30 FliM molecules per motor exist in two discrete populations, one tightly associated with the motor and the other undergoing stochastic turnover…. In many ways the bacterial flagellar motor is as an archetype macromolecular assembly, and our results may have further implications for the functional relevance of protein turnover in other large molecular complexes.”
This was no easy undertaking, specialized imaging techniques were needed in order for the Oxford team to be able to identify components of the rotor undergoing dynamic turnover in about 30- to 40-second timeframes. It’s currently unknown the reason for such turnover. Ideas consist of maintenance of the motor or function. Also, it appears that a signaling mechanism is involved with the turnover.
There is caution on the researchers part about speculating whether FliM turnover is involved in the switch function of the C ring, emphasizing that the exchange of FliM subunits could be either a cause or effect of motor reversal. It’s quite a remarkable feat and awesome design that can switch parts while spinning around at 60,000 rpm. Also, the researchers say nothing about evolution in this paper (like it would matter in understanding this very complex system that was believed to be just a simple blob at one point in time). The paper contained some outstanding work on how it operates!
The only theory that contains a vocabulary and concepts with explanatory resources to deal with observations that are rich in engineering that resembles man-made machinery and control language is creationism!