363
A tropoelastin gene has been identifi ed in amphibians as well as in avian and
mammalian species (Chung et al. 2006 ). In contrast, teleosts species possess two
tropoelastin genes with different tissue expression patterns. “General characteristics
of tropoelastins, such as alternating arrangements of hydrophobic and crosslinking
domains, are conserved across a wide phylogenetic range. However, the sequences
of these domains are highly variable, particularly when amphibian and teleost tropoelastins are included,” (Miao et al. 2009 ). It is suggested (Fritze et al. 2012 ) that
human ageing is accompanied by a destruction of the elastic vascular structure:
tropoelastin expression analysis shows that elastogenesis occurs throughout life
with constantly decreasing levels.
How to replace damaged elastin-rich tissue using tropoelastin is one of the
intriguing questions in biomedicine and biological materials science (Wise and
Weiss 2009 ). The biomimetic potential of tropoelastin is characterized in the following form: “This modular, multifaceted molecule is being exploited to enhance
the physical performance and biological presentation of engineered constructs to
augment and repair human tissues. These tissues include skin and vasculature, and
emphasize how growing knowledge of tropoelastin can be powerfully adapted to
add value to pre-existing devices like stents and novel, multi-featured biological
implants,” ( Mithieux et al. 2013 ).
Recently, attention is paid also to the tropoelastin-derived sequences which are
crucial for understanding of the structural mechanism that underlies the elastomeric
mechanical response of this specialized biological material. This statement can be
confi rmed by (Conticello and Carpenter Desai 2012 ):
“Tropoelastin and elastin-derived polypeptide sequences display a thermally
reversible phase transition above a lower critical solution temperature, Tt, which
coincides with the development of elastomeric restoring force in the material. The
functionally critical properties of native elastins can be recapitulated in polypeptides that are composed of concatenated sequences of oligopeptide repeat motifs
derived from tropoelastin; the most common of which are the pentapeptide
sequences (Val-Pro-Gly-Xaa-Gly). Moreover, biosynthetic methods have been
developed that enable the preparation of elastin-mimetic protein polymers that comprise complex sequences of defi ned macromolecular architecture (i.e., length, composition, and sequence); including multiblock copolymers. Thus, biosynthetic
elastin-mimetic polypeptides represent the best-characterized biologically derived
smart materials that have been prepared and analyzed to date,” (Conticello and
Carpenter Desai 2012 ).
Evolution of elastin is strongly related to the evolution of circulatory systems (see
for review Sage and Gray 1976 , 1979 , 1980 , 1981 ; Sage 1982 , 1983 ; Chalmers et al.
1999 ; Faury 2001 ). In the classical paper entitled “ Evolution of elastin structure ” (Sage
and Gray 1977 ), the authors tested the aortae of a number of vertebrates and invertebrates and reported as follow: “Comparison of purifi ed elastins from several vertebrate
groups reveals some striking differences in their amino acid compositions and properties, including the arrangement of the elastic fi bers in the aorta. The patterns of variations in amino acid composition suggest a mode of evolution which is different from
10 Marine Elastin
A tropoelastin gene has been identifi ed in amphibians as well as in avian and
mammalian species (Chung et al. 2006 ). In contrast, teleosts species possess two
tropoelastin genes with different tissue expression patterns. “General characteristics
of tropoelastins, such as alternating arrangements of hydrophobic and crosslinking
domains, are conserved across a wide phylogenetic range. However, the sequences
of these domains are highly variable, particularly when amphibian and teleost tropoelastins are included,” (Miao et al. 2009 ). It is suggested (Fritze et al. 2012 ) that
human ageing is accompanied by a destruction of the elastic vascular structure:
tropoelastin expression analysis shows that elastogenesis occurs throughout life
with constantly decreasing levels.
How to replace damaged elastin-rich tissue using tropoelastin is one of the
intriguing questions in biomedicine and biological materials science (Wise and
Weiss 2009 ). The biomimetic potential of tropoelastin is characterized in the following form: “This modular, multifaceted molecule is being exploited to enhance
the physical performance and biological presentation of engineered constructs to
augment and repair human tissues. These tissues include skin and vasculature, and
emphasize how growing knowledge of tropoelastin can be powerfully adapted to
add value to pre-existing devices like stents and novel, multi-featured biological
implants,” ( Mithieux et al. 2013 ).
Recently, attention is paid also to the tropoelastin-derived sequences which are
crucial for understanding of the structural mechanism that underlies the elastomeric
mechanical response of this specialized biological material. This statement can be
confi rmed by (Conticello and Carpenter Desai 2012 ):
“Tropoelastin and elastin-derived polypeptide sequences display a thermally
reversible phase transition above a lower critical solution temperature, Tt, which
coincides with the development of elastomeric restoring force in the material. The
functionally critical properties of native elastins can be recapitulated in polypeptides that are composed of concatenated sequences of oligopeptide repeat motifs
derived from tropoelastin; the most common of which are the pentapeptide
sequences (Val-Pro-Gly-Xaa-Gly). Moreover, biosynthetic methods have been
developed that enable the preparation of elastin-mimetic protein polymers that comprise complex sequences of defi ned macromolecular architecture (i.e., length, composition, and sequence); including multiblock copolymers. Thus, biosynthetic
elastin-mimetic polypeptides represent the best-characterized biologically derived
smart materials that have been prepared and analyzed to date,” (Conticello and
Carpenter Desai 2012 ).
Evolution of elastin is strongly related to the evolution of circulatory systems (see
for review Sage and Gray 1976 , 1979 , 1980 , 1981 ; Sage 1982 , 1983 ; Chalmers et al.
1999 ; Faury 2001 ). In the classical paper entitled “ Evolution of elastin structure ” (Sage
and Gray 1977 ), the authors tested the aortae of a number of vertebrates and invertebrates and reported as follow: “Comparison of purifi ed elastins from several vertebrate
groups reveals some striking differences in their amino acid compositions and properties, including the arrangement of the elastic fi bers in the aorta. The patterns of variations in amino acid composition suggest a mode of evolution which is different from
10 Marine Elastin