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Genetic Incorporation of Biosynthesized L-dihydroxyphenylalanine DOPA and Its Application to Protein Conjugation
Published on: August 24, 2018
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Halogenated DOPA in a Marine Adhesive Protein
Cheng Jun Sun1, Aasheesh Srivastava, Jack R Reifert
1Molecular, Cell & Developmental Biology Department, University of California at Santa Barbara, Santa Barbara, CA, USA.
The Journal of Adhesion
|February 4, 2010
Summary
Marine worms use a unique chlorinated amino acid in their underwater glue. This discovery reveals potential new roles for 2-chloro-DOPA in adhesion and defense for the sandcastle worm.
Area of Science:
- Marine Biology
- Biochemistry
- Materials Science
Background:
- The sandcastle worm (Phragmatopoma californica) builds protective tubes using a specialized underwater adhesive.
- This adhesive is primarily composed of proteins, including cement proteins Pc-1 and Pc-2, which contain the amino acid 3,4-dihydroxyphenyl-L-alanine (DOPA).
Purpose of the Study:
- To identify and characterize novel components within the sandcastle worm's adhesive.
- To investigate the chemical structure and potential functions of unusual amino acid derivatives found in the cement.
Main Methods:
- Partial acid hydrolysis of worm cement.
- Phenylboronate affinity chromatography to isolate catecholic amino acids.
- Tandem mass spectrometry and proton nuclear magnetic resonance ((1)H NMR) for structural analysis.
Main Results:
- Isolation of a significant amount of a halogenated DOPA derivative from the worm cement.
- Identification of the derivative as 2-chloro-4, 5-dihydroxyphenyl-L-alanine (2-chloro-DOPA) through advanced analytical techniques.
Conclusions:
- The sandcastle worm cement contains a novel chlorinated amino acid, 2-chloro-DOPA.
- This compound may play a role in the worm's underwater adhesion capabilities and potentially in chemical defense mechanisms.
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