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Related Experiment Video

Updated: Jun 14, 2026

OaAEP1-Mediated Enzymatic Synthesis and Immobilization of Polymerized Protein for Single-Molecule Force Spectroscopy

OaAEP1-Mediated Enzymatic Synthesis and Immobilization of Polymerized Protein for Single-Molecule Force Spectroscopy

Published on: February 5, 2020

A Stevedore's protein knot.

Daniel Bölinger¹, Joanna I Sułkowska, Hsiao-Ping Hsu

¹Department of Physics, Johannes Gutenberg-Universität Mainz, Mainz, Germany.

Plos Computational Biology

|April 7, 2010

Summary

This summary is machine-generated.

Researchers discovered the smallest and most complex protein knots to date. Folding simulations revealed a potential mechanism for forming these intricate Stevedore knots through a single loop flip.

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Area of Science:

Biochemistry
Structural Biology
Computational Biology

Background:

Protein knots are increasingly recognized as important structural motifs, with seven types identified.
The folding mechanisms of these complex protein structures remain largely unknown.
Recent advancements in experiments and simulations are beginning to elucidate knot formation.

Purpose of the Study:

To investigate the folding mechanism of the most complex and smallest protein knots discovered.
To understand how the topologically intricate Stevedore knot forms in proteins.
To explore the formation of protein knots in a 92-amino acid fragment and an alpha-haloacid dehalogenase.

Main Methods:

Analysis of new protein structures from the Protein Data Bank.
Structure-based coarse-grained folding simulations.
Topological analysis of protein knot complexity.

Main Results:

Identification of the smallest protein knot (92 amino acids) and the most complex knot (Stevedore knot with six crossings) to date.
Uncovering a plausible folding mechanism for the Stevedore knot involving a single loop flip.
Demonstration of how complex topological structures can arise in small protein fragments.

Conclusions:

Protein knots, particularly the Stevedore knot, can form through relatively simple mechanisms like a single loop flip.
The discovery of small, complex knots challenges previous assumptions about protein folding.
Further research into protein knot folding is crucial for understanding protein structure and function.