Abstract

Abductin is a natural elastomer found as the major component of the elastic hinge ligament in marine scallops. Until now, very little was known about the structure and function of this compressible elastomer. Biochemical studies of a synthetic 25 amino acid peptide of abductin produces fibers that assemble into a gel matrix at room temperature. Further investigation of this phenomenon via temperature-dependent turbidimetry revealed that this peptide self-assembles or aggregates at 23 °C. Secondary structural studies of this peptide at different temperatures revealed that it undergoes an inverse temperature transition much like soluble elastin peptides. Replacing phenylalanine with alanine in this sequence resulted in no observable inverse temperature transition although gel formation and self-assembly persisted at room temperature as evidenced by electron microscopy and temperature-dependent turbidimetry of the dried modified peptide. Based on these data and molecular modeling predictions, a 47 amino acid abductin peptide mimetic was developed that also formed a gel-like aggregate much like the aggregate formed by the 25 amino acid abductin sequence. The abductin peptide mimetic proved to have superior gel stability as evidenced by moisture loss kinetics. Mechanical properties determination of the abductin peptide mimetic afforded a measurable elastic modulus even in the absence of covalent cross-linking. A “hydroelasticity” model is proposed to explain the possible mechanism of elasticity in this gel aggregate.

The purpose of the research described herein is to develop a bioelastomer that is suitable for the repair of damaged hyaline cartilage in patients having degenerative arthritic diseases. It is expected that this research will yield a novel treatment for the repair of cartilage that circumvents the shortcomings of the currently used methods for cartilage resurfacing.

LLU Discipline

Biochemistry

Department

Biochemistry

School

Graduate School

First Advisor

Lawrence B. Sandberg

Second Advisor

Mario Blanco

Third Advisor

E. Clifford Herrmann

Fourth Advisor

Subburaman Mohan

Fifth Advisor

Philip J. Roos

Sixth Advisor

Antonio M. Tamburro

Degree Name

Doctor of Philosophy (PhD)

Degree Level

Ph.D.

Year Degree Awarded

2001

Date (Title Page)

3-2001

Language

English

Library of Congress/MESH Subject Headings

Elastomers; Mollusca -- physiology; Calcium Carbonate -- analysis; Ligaments -- physiology; Proteins -- analysis; Osteoarthritis -- therapy

Type

Dissertation

Page Count

xiii; 99

Digital Format

PDF

Digital Publisher

Loma Linda University Libraries

Usage Rights

This title appears here courtesy of the author, who has granted Loma Linda University a limited, non-exclusive right to make this publication available to the public. The author retains all other copyrights.

Collection

Loma Linda University Electronic Theses and Dissertations

Collection Website

http://scholarsrepository.llu.edu/etd/

Repository

Loma Linda University. Del E. Webb Memorial Library. University Archives

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