Open Letters

More thoughts on folding and form

Maurizio Brunori Arianna Brunori
By Maurizio Brunori and Arianna Brunori
Oct. 28, 2020

We were pleased to read Sudha Neelam’s pleasant and stimulating essay, “The art of paper folding and the science of protein folding,”in ASBMB Today.

Origami-bird-300x161.jpg
Daniel Álvasd/ Unsplash

Outlining the similarity between an origami and a folded protein is quite popular, since in both the form combines beauty and functional relevance. In both cases, the mechanism of folding to achieve the final state is complex. This similarity has been taken further to highlight that a misfolded origami mimics in some way a misfolded protein seen at the onset of neurodegenerative diseases that develop via irreversible population of an amyloid state by extensive misaggregation.

Folding-protein-300x315.jpg
Jawahar Swaminathan/
European Bioinformatics Institute

We should, however, recall one difference between folding a paper sheet and a polypeptide chain, a difference that is of fundamental significance.

The complex course of action to fold a paper sheet to produce origami of a chosen shape demands that precise information be injected in the procedure by an operator (in this specific case, Nihkil, the son of the writer Sudha Neelam). The order of guided steps is essential to overcome the loss of entropy coupled to the creation of an ordered object, such as a classical origami sculpture.

David-300x360.jpg
Jörg Bittner Unna/Wikimedia Commons

In the case of folding a complex 3D structurestarting from one disordered polypeptide, the information guiding the series of events/chemical steps leading to the globular protein is imprinted within the amino acid sequence. The primary structure itself is also the code carrying the instructions on how to fold in water and thereby the information to overcome the huge, unfavorable entropy loss.

In water, the amino acid sequence of a protein conforms beautifully to Aristotle’s definition of substance, the intimate ensemble of matter and form (in Greek: “synolon”), insofar as the amino acid sequence contains in itself the reason for becoming what it is (in Latin: “substantia causa sui”). In this respect, we can compare the amino acid sequence to the marble block as seen by Michelangelo Buonarroti. In Michelangelo’s view, the artist need only bring into actuality the form that already lies in the marble block by chiseling away the superfluous material.

Likewise, as shown by Nobel laureate Christian Anfinsen, the amino acid sequence embeds from the beginning the properties that will characterize the protein in the final functionally competent native state, needing only water to pass from potentiality into actuality.

 

Enjoy reading ASBMB Today?

Become a member to receive the print edition monthly and the digital edition weekly.

Learn more
Maurizio Brunori
Maurizio Brunori

Maurizio Brunori is emeritus president of the National Academy of the Lincei and professor emeritus at the Sapienza University of Rome.

Arianna Brunori
Arianna Brunori

Arianna Brunori is a Ph.D. student in medieval philosophy at the Scuola Normale Superiore di Pisa.

Get the latest from ASBMB Today

Enter your email address, and we’ll send you a weekly email with recent articles, interviews and more.

Latest in Opinions

Opinions highlights or most popular articles

Rethinking the promotion letter
Diversity

Rethinking the promotion letter

Feb. 22, 2024

Writers of a recent article suggest a new strategy for retaining and advancing underrepresented faculty.

Escape to the ice
Essay

Escape to the ice

Feb. 19, 2024

Outside the lab, two scientists strap on their skates and grab their sticks.

Equitable hiring strategies for a diversified faculty
Diversity

Equitable hiring strategies for a diversified faculty

Feb. 8, 2024

An evidence-based road map describes six important strategies for hiring faculty from historically marginalized and excluded backgrounds.

We're saving some trees
Society News

We're saving some trees

Feb. 5, 2024

ASBMB Today will now be printed four times a year.

The legacy of Geraldine P. Woods
Diversity

The legacy of Geraldine P. Woods

Feb. 1, 2024

A trailblazer in science and diversity, she helped create NIH programs to broaden participation in STEM

I survived sudden cardiac arrest and 37 days in a coma — then the hard part began
Essay

I survived sudden cardiac arrest and 37 days in a coma — then the hard part began

Jan. 25, 2024

“The neurologist on my team said there were ‘no purposeful signs of activity’ … and weaned my phenobarbital dose down. I woke up the next morning.”