Session 4.1g - Pre-Reading [Article] Flashcards
https://www.sciencemag.org/news/2016/07/protein-designer-aims-revolutionize-medicines-and-materials?utm_source=general_public&utm_medium=youtube&utm_campaign=vid-protein-fold-5886
What shapes can 3D printed proteins make?
- Rings
- Balls
- Tubes
- Cages
etc.
What has David Baker and his team been doing?
Figuring out how long strings of amino acids fold up into the 3D proteins that form the working machinery of life. Now, he and colleagues have taken this ability and turned it around to design and then synthesize unnatural proteins intended to act as everything from medicines to materials.
What applications has virtuoso proteinmaking yielded so far?
- An experimental HIV vaccine
- Novel proteins that aim to combat all strains of the influenza viruses simultaneously
- Carrier molecules that can ferry reprogrammed DNA into cells
- New enzymes that help microbes suck carbon dioxide out of the atmosphere and convert it into useful chemicals.
Cages of proteins can be made from as many as how many proteins?
120
How can proteinmaking be used to combat HIV?
To create an experimental HIV vaccine
How can proteinmaking be used to combat influenza?
To create novel proteins that aim to combat all strains of the influenza viruses simultaneously
How can proteinmaking be used to involve DNA?
To create carrier molecules that can ferry reprogrammed DNA into cells
How can proteinmaking be used for enzymes?
To create new enzymes that help microbes suck carbon dioxide out of the atmosphere and convert it into useful chemicals.
How can proteinmaking be used for carbon dioxide?
To create new enzymes that help microbes suck carbon dioxide out of the atmosphere and convert it into useful chemicals.
Cages can be assembled from as many 120 designer proteins.
What could this do?
This could open the door to a new generation of molecular machines.
What is the newfound ability of designing novel proteins akin to?
If the ability to read and write DNA spawned the revolution of molecular biology, the ability to design novel proteins could transform just about everything else
What implications could the design of novel proteins lead to?
Nobody knows the implications because it has the potential to impact dozens of different disciplines
How far back do efforts to predict how proteins fold and using that information to fashion novel versions date back?
Decades
When did biochemists at the U.S. National Institutes of Health (NIH) recognise that each protein folds itself into an intrinsic shape?
In the early 1960s
How can you lose a protein’s 3D structure?
Heat a protein in a solution and its 3D structure will generally unravel
What happens when you heat a protein in solution?
Its 3D structure will generally unravel
What happens after proteins are heated and structures unravelled?
The proteins refold themselves as soon as they cool.
Proteins can be heated and their 3D structure will generally unravel. However, as soon as they cool, the proteins refold themselves. What does this imply about their structure?
It implies that their structure stems from the interactions between different amino acids, rather than from some independent molecular folding machine inside cells
How do we know protein structure is dependent on interactions between amino acids rather than from independent molecular folding machinery inside the cell?
Heat a protein in a solution and its 3D structure will generally unravel. However, these proteins will refold themselves as soon as they cool
What is needed to be able to understand how an amino acid sequence would assume its final shape?
If researchers could determine the strength of all those interactions [between amino acids], they might be able to calculate how any amino acid sequence would assume its final shape
What is the protein folding problem?
Understanding how amino acid interactions lead to the final protein shape.
What is essential for life from DNA to proteins?
The machinery for building proteins is essential for all life on earth
What does building proteins begin with?
Building proteins begins with DNA’s genetic code.
What is the relationship between DNA, genes and amino acids?
In protein-coding regions of genes, each amino acid is encoded by three rungs of the DNA ladder.
How many amino acids make up the building blocks of proteins?
Twenty such amino acids make up the building blocks of proteins.
What is the first step in DNA becoming a protein?
Double stranded DNA is transcribed into single-stranded RNA, which is then sent to the ribosome where proteins are manufactured.
How does RNA become an amino acid?
A molecular machine called the ribosome translates each RNA coding sequence into an amino acid, building up a growing protein chain.
How are amino acids formed into a protein?
Forces between amino acids cause a linear chain to fold up on itself, creating a functional 3D protein.
How can proteins structures be configured experimentally?
- X-ray crystallography
- Nuclear magnetic resonance (NMR) spectroscopy
What is a disadvantage of using x-ray crystallography/NMR to determine protein structures?
It’s slow and expensive
How many proteins does the Protein Data Bank hold for known structures?
Only roughly 110,000 proteins - out of the hundreds of millions or more thought to exist
Why would it be beneficial to know a proteins’ shape?
Knowing the 3D structures of those other proteins would offer biochemists vital insights into each molecule’s function, such as whether it serves to ferry ions across a cell membrane or catalyze a chemical reaction
It would also give chemists valuable clues to designing new medicines
What is the next step after X-ray crystallography/NMR spec to studying protein shape?
So, instead of waiting for the experimentalists, computer modelers such as Baker have tackled the folding problem with computer models.
What are the two broad kinds of folding models?
- Homology models
- Ab initio modeling
How do homology models works?
These compare the amino acid sequence of a target protein with that of a template - a protein with a similar sequence and a known 3D structure
The models adjust their prediction for the target’s shape based on the differences between its amino acid sequence and that of the template