Dityrosine Crossed-linked Amyloid-like Fibrils as Bionanomaterials

Iraqi Journal of Nanotechnology ◽

10.47758/ijn.vi1.23 ◽

2020 ◽

pp. 22-32

Author(s):

Youssra Kareem Al-Hilaly ◽

Mahmoud Bukar Maina ◽

Alaa Abdul-Sada ◽

Louise Serpell

Keyword(s):

Tissue Engineering ◽

Amino Acid ◽

Regenerative Medicine ◽

Amino Acid Sequence ◽

Bond Formation ◽

Model System ◽

Tyrosine Residues ◽

Cross Links ◽

Amyloidogenic Peptides ◽

Biophysical Techniques

Bionanomaterials have great potential for applications in tissue engineering and regenerative medicine. Recently, amyloid-like fibrils have been used in bionanomaterials preparation due to their stability and biocompatibility. Covalent dityrosine bond formation has been identified as a useful tool in the design of such bionanomaterials. In this study, two short amyloidogenic peptides containing tyrosine residues with the amino acid sequence HYFNIF and VIYKI, were used as a model system to investigate the effect of oxidation and their ability to form dityrosine cross-links. Using a range of biophysical techniques, we showed that both HYFNIF and VIYKI form dityrosine cross-linked fibrils using copper-catalysis, and phosphate buffer is more efficient in dityrosine formation. Dityrosine forms more rapidly in VIYKI fibrils compared to HYFNIF due to the fibrillar architecture. Dityrosine cross-linked HYFNIF and VIYKI fibrils could be useful to prepare bionanomaterials.

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The identification of protected tyrosine residues in iron-ovotransferrin

Biochemical Journal ◽

10.1042/bj2010647 ◽

1982 ◽

Vol 201 (3) ◽

pp. 647-651 ◽

Cited By ~ 17

Author(s):

J Williams

Keyword(s):

Amino Acid ◽

Amino Acid Sequence ◽

Polypeptide Chain ◽

Tyrosine Residues ◽

Metal Atoms

Tetranitromethane reacts with essentially all 21 tyrosine residues of iron-free ovotransferrin. In iron-ovotransferrin, 7 mol of tyrosine/mol of protein are unreactive. Peptides containing the unreactive tyrosine residues were isolated from digests of nitrated iron-ovotransferrin. By comparing the structures of the peptides with the amino acid sequence of ovotransferrin it is found that there are ten protected residues occupying positions 42, 82, 92, 188, 319, 415, 431, 521 and 524 in the polypeptide chain. The problem of identifying the tyrosine residues that form bonds with the metal atoms is discussed.

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Rapid assembly and profiling of an anticoagulant sulfoprotein library

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1905177116 ◽

2019 ◽

Vol 116 (28) ◽

pp. 13873-13878 ◽

Cited By ~ 11

Author(s):

Emma E. Watson ◽

Jorge Ripoll-Rozada ◽

Ashley C. Lee ◽

Mike C. L. Wu ◽

Charlotte Franck ◽

...

Keyword(s):

Amino Acid ◽

Amino Acid Sequence ◽

Anticoagulant Activity ◽

Functional Characterization ◽

Serine Proteinase ◽

One Pot ◽

Tyrosine Residues ◽

Thrombin Inhibition ◽

Protein Library ◽

Target Molecules

Hematophagous organisms produce a suite of salivary proteins which interact with the host’s coagulation machinery to facilitate the acquisition and digestion of a bloodmeal. Many of these biomolecules inhibit the central blood-clotting serine proteinase thrombin that is also the target of several clinically approved anticoagulants. Here a bioinformatics approach is used to identify seven tick proteins with putative thrombin inhibitory activity that we predict to be posttranslationally sulfated at two conserved tyrosine residues. To corroborate the biological role of these molecules and investigate the effects of amino acid sequence and sulfation modifications on thrombin inhibition and anticoagulant activity, a library of 34 homogeneously sulfated protein variants were rapidly assembled using one-pot diselenide-selenoester ligation (DSL)-deselenization chemistry. Downstream functional characterization validated the thrombin-directed activity of all target molecules and revealed that posttranslational sulfation of specific tyrosine residues crucially modulates potency. Importantly, access to this homogeneously modified protein library not only enabled the determination of key structure–activity relationships and the identification of potent anticoagulant leads, but also revealed subtleties in the mechanism of thrombin inhibition, between and within the families, that would be impossible to predict from the amino acid sequence alone. The synthetic platform described here therefore serves as a highly valuable tool for the generation and thorough characterization of libraries of related peptide and/or protein molecules (with or without modifications) for the identification of lead candidates for medicinal chemistry programs.

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Amino acid sequences C-terminal to the cross-links in bovine elastin

Biochemical Journal ◽

10.1042/bj1850611 ◽

1980 ◽

Vol 185 (3) ◽

pp. 611-616 ◽

Cited By ~ 16

Author(s):

K M Baig ◽

M Vlaovic ◽

R A Anwar

Keyword(s):

Amino Acid ◽

Amino Acid Sequences ◽

Amino Acid Residues ◽

Tyrosine Residues ◽

Lysine Residues ◽

Cross Links ◽

The Cross

All the desmosine-containing elastolytic peptides of bovine ligamentum-nuchae elastin have now been examined for amino acid sequences C-terminal to the cross-links. In addition, amino acid residues C-terminal to lysine residues in bovine tropoelastin were also examined. No tyrosine C-terminal to cross-links in bovine elastin or C-terminal to lysine in tropoelastin was detected. Apparently all the tyrosine residues C-terminal to lysine residues in pig tropoelastin are replaced with phenylalanine in bovine tropoelastin. All the data presented are consistent with the scheme proposed for the formation of desmosine and isodesmosine cross-links of elastin by Gerber & Anwar [(1975) Biochem. J. 149, 685-695].

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The staining pattern of the tropomyosin sequence is displayed in a new paracrystal

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100142372 ◽

1986 ◽

Vol 44 ◽

pp. 150-151

Author(s):

M.K. Lamvik ◽

L.L. Klatt

Keyword(s):

Amino Acid ◽

Amino Acid Sequence ◽

Staining Pattern ◽

Banding Patterns ◽

Mass Thickness ◽

New Form

Tropomyosin paracrystals have been used extensively as test specimens and magnification standards due to their clear periodic banding patterns. The paracrystal type discovered by Ohtsuki1 has been of particular interest as a test of unstained specimens because of alternating bands that differ by 50% in mass thickness. While producing specimens of this type, we came across a new paracrystal form. Since this new form displays aligned tropomyosin molecules without the overlaps that are characteristic of the Ohtsuki-type paracrystal, it presents a staining pattern that corresponds to the amino acid sequence of the molecule.

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Isolation and Structural Charaderization of a Potent Inhibitor of Coagulation Factor Xa from the Leech Haementeria ghilianii

Thrombosis and Haemostasis ◽

10.1055/s-0038-1646610 ◽

1989 ◽

Vol 61 (03) ◽

pp. 437-441 ◽

Cited By ~ 28

Author(s):

Cindra Condra ◽

Elka Nutt ◽

Christopher J Petroski ◽

Ellen Simpson ◽

P A Friedman ◽

...

Keyword(s):

Molecular Weight ◽

Salivary Gland ◽

Amino Acid ◽

Amino Acid Sequence ◽

Western Blot ◽

Potent Inhibitor ◽

Factor Xa ◽

Coagulation Factor ◽

Sds Page ◽

Bovine Factor

SummaryThe present work reports the discovery and charactenzation of an anticoagulant protein in the salivary gland of the giant bloodsucking leech, H. ghilianii, which is a specific and potent inhibitor of coagulation factor Xa. The inhibitor, purified to homogeneity, displayed subnanomolar inhibition of bovine factor Xa and had a molecular weight of approximately 15,000 as deduced by denaturing SDS-PAGE. The amino acid sequence of the first 43 residues of the H. ghilianii derived inhibitor displayed a striking homology to antistasin, the recently described subnanomolar inhibitor of factor Xa isolated from the Mexican leech, H. officinalis. Antisera prepared to antistasin cross-reacted with the H. ghilianii protein in Western Blot analysis. These data indicate that the giant Amazonian leech, H. ghilianii, and the smaller Mexican leech, H. officinalrs, have similar proteins which disrupt the normal hemostatic clotting mechanisms in their mammalian host’s blood.

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Paris I Dysfibrinogenemia: A Point Mutation in Intron 8 Results in Insertion of a 15 Amino Acid Sequence in the Fibrinogen γ-Chain

Thrombosis and Haemostasis ◽

10.1055/s-0038-1651583 ◽

1993 ◽

Vol 69 (03) ◽

pp. 217-220 ◽

Cited By ~ 12

Author(s):

Jonathan B Rosenberg ◽

Peter J Newman ◽

Michael W Mosesson ◽

Marie-Claude Guillin ◽

David L Amrani

Keyword(s):

Amino Acid ◽

Amino Acid Sequence ◽

Point Mutation ◽

Genomic Dna ◽

Comparative Sequence Analysis ◽

Chain Gene ◽

Molecular Defect ◽

Nucleotide Position ◽

Normal Individuals ◽

Polymerase Chain

SummaryParis I dysfibrinogenemia results in the production of a fibrinogen molecule containing a functionally abnormal γ-chain. We determined the basis of the molecular defect using polymerase chain reaction (PCR) to amplify the γ-chain region of the Paris I subject’s genomic DNA. Comparative sequence analysis of cloned PCR segments of normal and Paris I genomic DNA revealed only an A→G point mutation occurring at nucleotide position 6588 within intron 8 of the Paris I γ-chain gene. We examined six normal individuals and found only normal sequence in this region, indicating that this change is not likely to represent a normal polymorphism. This nucleotide change leads to a 45 bp fragment being inserted between exons 8 and 9 in the mature γparis I chain mRNA, and encodes a 15 amino acid insert after γ350 [M-C-G-E-A-L-P-M-L-K-D-P-C-Y]. Alternative splicing of this region from intron 8 into the mature Paris I γ-chain mRNA also results after translation into a substitution of S for G at position γ351. Biochemical studies of 14C-iodoacetamide incorporation into disulfide-reduced Paris I and normal fibrinogen corroborated the molecular biologic predictions that two additional cysteine residues exist within the γpariS I chain. We conclude that the insertion of this amino acid sequence leads to a conformationallyaltered, and dysfunctional γ-chain in Paris I fibrinogen.

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Complete Covalent Structure of Human Platelet Factor 4

Thrombosis and Haemostasis ◽

10.1055/s-0038-1657071 ◽

1979 ◽

Vol 42 (05) ◽

pp. 1652-1660 ◽

Cited By ~ 4

Author(s):

Francis J Morgan ◽

Geoffrey S Begg ◽

Colin N Chesterman

Keyword(s):

Amino Acids ◽

Molecular Weight ◽

Amino Acid ◽

Amino Acid Sequence ◽

Human Platelet ◽

Platelet Factor 4 ◽

Platelet Factor ◽

Disulphide Bonds ◽

Covalent Structure

SummaryThe amino acid sequence of the subunit of human platelet factor 4 has been determined. Human platelet factor 4 consists of identical subunits containing 70 amino acids, each with a molecular weight of 7,756. The molecule contains no methionine, phenylalanine or tryptophan. The proposed amino acid sequence of PF4 is: Glu-Ala-Glu-Glu-Asp-Gly-Asp-Leu-Gln-Cys-Leu-Cys-Val-Lys-Thr-Thr-Ser- Gln-Val-Arg-Pro-Arg-His-Ile-Thr-Ser-Leu-Glu-Val-Ile-Lys-Ala-Gly-Pro-His-Cys-Pro-Thr-Ala-Gin- Leu-Ile-Ala-Thr-Leu-Lys-Asn-Gly-Arg-Lys-Ile-Cys-Leu-Asp-Leu-Gln-Ala-Pro-Leu-Tyr-Lys-Lys- Ile-Ile-Lys-Lys-Leu-Leu-Glu-Ser. From consideration of the homology with p-thromboglobulin, disulphide bonds between residues 10 and 36 and between residues 12 and 52 can be inferred.

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