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Protein Folding

Protein Folding

Protein Folding

Protein Folding

Proteins are chains of amino acids linked together by peptide bonds. Upon synthesis, a protein folds into a three-dimensional conformation, critical to its biological function. Interactions between its constituent amino acids guide protein folding, and hence the protein structure is primarily dependent on its amino acid sequence.
Protein Structure Is Critical to Its Biological Function
Proteins perform a wide range of biological functions such as catalyzing chemical reactions, providing...

Protein Folding

Protein Folding

Protein and Protein Structure

Protein and Protein Structure

Proteins are one of the most abundant organic molecules in living systems and have the most diverse range of functions of all macromolecules. Proteins may be structural, regulatory, contractile, or protective. They may serve in transport, storage, or membranes; or they may be toxins or enzymes. Their structures, like their functions, vary greatly. They are all, however, amino acid polymers arranged in a linear sequence.
A protein's shape is critical to its function. For example, an enzyme...

Protein Organization

Protein Organization

Protein Organization

Protein Organization

Proteins are polymers of amino acid residues. They are versatile and responsible for different cellular functions, including DNA replication, molecular transport, catalysis, and structural support. Proteins have a hierarchical structure comprising at least three levels of organization: primary, secondary, and tertiary structure. Some large proteins have a quaternary structure where individual protein subunits are linked together.
The primary structure of a protein is its amino acid sequence....

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Updated: Mar 14, 2026

A Protocol for Computer-Based Protein Structure and Function Prediction

A Protocol for Computer-Based Protein Structure and Function Prediction

Published on: November 3, 2011

Basic units of protein structure, folding, and function.

Igor N Berezovsky¹, Enrico Guarnera², Zejun Zheng²

¹Bioinformatics Institute (BII), Agency for Science, Technology and Research (A*STAR), 30 Biopolis Street, #07-01, Matrix, 138671, Singapore; Department of Biological Sciences (DBS), National University of Singapore (NUS), 8 Medical Drive, 117579, Singapore.

Progress in Biophysics and Molecular Biology

|October 5, 2016

Summary

This summary is machine-generated.

Researchers discovered closed loops as the minimal unit of protein structure, forming stable protein folds and enabling functional design. These elementary functional loops (EFLs) offer insights into early protein evolution and enzyme design.

Keywords:

Closed loops Evolution Hierarchy of domain structure Protein folding Protein function Protein structure

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A Protocol for Computer-Based Protein Structure and Function Prediction

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Published on: November 3, 2011

Application of I TASSER, trRosetta, UCSF Chimera, HADDOCK server, and HEX loria for De Novo and In Silico Design of Proteins

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Published on: July 8, 2025

Protein WISDOM: A Workbench for In silico De novo Design of BioMolecules

Protein WISDOM: A Workbench for In silico De novo Design of BioMolecules

Published on: July 25, 2013

Area of Science:

Structural biology
Protein folding
Evolutionary biochemistry

Background:

Investigating protein domain hierarchy and discontinuous domains questioned the minimal structural unit.
A hypothesis proposed the polypeptide backbone's crucial role in defining globular protein elementary units.

Purpose of the Study:

To explore the fundamental principles governing protein folding and stability in early evolution.
To identify the minimal structural and functional units of proteins.
To establish rules for designing enzymatic functions based on evolutionary relationships.

Main Methods:

Analysis of protein domain hierarchy and discontinuous domains.
Hypothesis-driven investigation of polypeptide backbone's role.
Consideration of simplified protein sequences.
Identification and analysis of elementary functional loops (EFLs).

Main Results:

Discovery of closed loops as the minimal structural unit of protein domains.
Elucidation of the loop-n-lock structure, crucial for protein stability and co-translational folding.
Identification of elementary functional loops (EFLs) as units of protein function, potentially descending from prebiotic peptides.
Demonstration of how EFLs can map evolutionary relationships between protein superfamilies and folds.

Conclusions:

Closed loops represent the fundamental building blocks of protein structure and function.
EFLs provide a framework for understanding protein evolution and designing novel enzymatic functions.
Generalized descriptors of elementary functions can advance computational protein design.