Is this evidence?

No, it is not.

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On to the seventh installment:

The two primary rotary machines in the bacterial membrane are the flagellum and the ATP synthase. With both machines, an influx of protons is used to drive the rotors, giving rise to motility and ATP synthesis, respectively. The source of these protons typically comes from metabolism, where the transport of electrons is tied to the efflux of protons (the electron transport chain). But what happens if the bacteria find themselves in an environment where metabolism cannot be carried out? Do they simply die?

Recent research has shown that bacteria can use a protein known as proteorhodopsin to absorb photons and use this energy to drive the efflux of protons. In other words, no they don’t die; several bacteria come with a solar powered back-up system

See here for a more detailed description.

What’s also interesting is that this little solar power system uses the same basic design as the receptors in your eye. Pieces and parts of eye may have been front-loaded into the first cells.

I have previously written about the genetic code from the perspective of design. A new study builds on this theme, suggesting that the genetic code is optimized on many different levels:

Alon and his doctoral student Shalev Itzkovitz compared the real genetic code to alternative, hypothetical genetic codes with equivalent codon-amino acid assignment characteristics. Remarkably, Itzkovitz and Alon showed that the real genetic code was superior to the vast majority of alternative genetic codes in terms of its ability to encode other information in protein-coding genes–such as splice sites, mRNA secondary structure, or regulatory signals.

Itzkovitz and Alon also demonstrated that the real genetic code provides for the quickest incorporation of a stop signal–compared to most of the alternative genetic codes–in cases where protein synthesis has gone amiss (situations that scientists call “frameshift errors”). This helps the cell to conserve its energy and resources.

“We think that the ability to carry parallel codes–or information beyond the amino acid code–may be a side effect of selection for avoiding aberrant protein synthesis,” says Itzkovitz. “These parallel codes were probably exploited during evolution to allow genes to support a wide range of signals to regulate and modify biological processes in cells.”

That the code may be optimized in terms of using stop codons to conserve cellular energy, splice site placement, and regulation clearly suggests that this code has not only been “exploited during evolution,” but may have also shaped it. Taken together, we have the echo of foresight.

I previously introduced the reader to the enhanced complexity that is seen in eukaryotic cells and asked why it is that eukaryotes are like this. We then considered an experiment using GFP that helped us to appreciate one way in which the eukaryal and bacterial cell plans are different: yeast, but not bacteria, were able to efficiently fold an artificial multi-domain protein. Let us there pause to consider this in more detail.

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