Tyrannosaurus rex

Speaking about creationists (so perhaps not OT), I saw this work on making better proteins from scratch. This will not make anti-scientists happy:

“Our aim is to design new proteins from principles we discover studying natural proteins,” explains co-author Christopher C. Moser, PhD, Associate Director of the Johnson Foundation at Penn. “For example, we found that natural proteins are complex and fragile and when we make new proteins we want them to be simple and robust. That’s why we’re not re-engineering a natural protein, but making one from scratch.”

Currently, protein engineers take an existing biochemical scaffold from nature and tweak it a bit structurally to make it do something else. “This research demonstrates how we used a set of simple design principles, which challenge the kind of approaches that have been used to date in reproducing natural protein functions,” says Dutton. [Bold added.]

The researchers have made a new oxygen carrier, a hemo-not-a-globin-but-a-functional-bundle, with the intention to make miniature chemical reactors:

To build their protein, the Penn team started with just three amino acids, which code for a helix-shaped column. From this, they assembled a four-column bundle with loops that resembles a simple candelabra. They added a heme, a chemical group that contains an iron atom, to bind oxygen molecules. They also added another amino acid called glutamate to add strain to the candelabra to help the columns open up to capture the oxygen. Since heme and oxygen degrade in water, the researchers also designed the exteriors of the columns to repel water to protect the oxygen payload inside.

When they are satisfied with a sequence they use E. coli as a host for making the protein.

“This exercise is like making a bus,” says Dutton. “First you need an engine and we’ve produced an engine. Now we can add other things on to it. Using the bound oxygen to do chemistry will be like adding the wheels. Our approach to building a simple protein from scratch allows us to add on, without getting more and more complicated.” [Bold added.]

Nature produces proteins that are too complex and fragile for proficient designers, which is why they make up a real design rule set and likes the designed result molecular “engines”.

PS. They also walk dogs.