Biosynthetic pathway of desmosines in elastin

1. Elastins purified by various methods from the ligamentum nuchae and the lungs of cattle of various ages were analysed for amino acid compositions and lysine-derived cross-links. 2. In fully mature elastins from adults the main cross-links were desmosine, isodesmosine and lysinonorleucine and the so-called aldol-condensation product. Trace amounts of merodesmosine were also found. 3. During the normal maturation of elastins the amounts of desmosine, isodesmosine and lysinonorleucine increased, whereas the aldol-condensation product and intact lysine residues decreased and merodesmosine remained the same. 4. Elastins from young animals contained significant amounts of dehydromerodesmosine whereas elastins from adults contained virtually nil. Evidence is presented which suggests that the biosynthetic pathway of desmosine and isodesmosine proceeds via the aldol-condensation product and dehydromerodesmosine.

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The chemistry of the collagen cross-links. The characterization of Fraction C, a possible artifact produced during the reduction of collagen fibres with borohydride

Biochemical Journal ◽

10.1042/bj1350657 ◽

1973 ◽

Vol 135 (4) ◽

pp. 657-665 ◽

Cited By ~ 44

Author(s):

Simon P. Robins ◽

Allen J. Bailey

Keyword(s):

Aldol Condensation ◽

Condensation Product ◽

Reduced Form ◽

Borohydride Reduction ◽

Cross Link ◽

Collagen Fibres ◽

Isolation And Identification ◽

Cross Links

The present paper describes the isolation and identification of a major radioactive component of borotritide-reduced collagen, previously designated Fraction C. The derived structure for the compound confirms that it is identical with the ‘post-histidine’ component described by Tanzer et al. (1973) and given the trivial name histidino-hydroxymerodesmosine. Detailed studies of the effects of acid pH on the formation of Fraction C after borohydride reduction demonstrated the apparent lability of the non-reduced form, thus confirming our previous findings (Bailey & Lister, 1968). Inhibition of the formation of this component by the acid treatment appears to be due to protonation of the histidine imidazole group. Since the only new component formed on reduction of the acid-treated fibres was the reduced aldol condensation product, these results indicate that neither the histidine nor the hydroxylysine residues can be involved in covalent linkage with the aldol condensation product in the native fibre. It is suggested therefore that the proposed non-reduced aldimine form of Fraction C does not exist as an intermolecular cross-link in vivo. Thus the presence of histidino-hydroxymerodesmosine as a tetrafunctional cross-link in reduced collagen fibres is a result of a base-catalysed reaction promoted by the borohydride-reduction procedure and this component must therefore be considered as an artifact.

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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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Characterization of Chemical Impurities in Glutaraldehyde

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100116723 ◽

1975 ◽

Vol 33 ◽

pp. 620-621

Author(s):

B. J. Grenon ◽

A. J. Tousimis

Keyword(s):

Glutaric Acid ◽

Spectroscopic Analysis ◽

Aldol Condensation ◽

Condensation Product ◽

Amorphous Solid ◽

Water Soluble ◽

Impurity Component ◽

Chemical Impurities ◽

Soluble Liquid

Ever since the introduction of glutaraldehyde as a fixative in electron microscopy of biological specimens, the identification of impurities and consequently their effects on biologic ultrastructure have been under investigation. Several reports postulate that the impurities of glutaraldehyde, used as a fixative, are glutaric acid, glutaraldehyde polymer, acrolein and glutaraldoxime.Analysis of commercially available biological or technical grade glutaraldehyde revealed two major impurity components, none of which has been reported. The first compound is a colorless, water-soluble liquid with a boiling point of 42°C at 16 mm. Utilizing Nuclear Magnetic Resonance (NMR) spectroscopic analysis, this compound has been identified to be — dihydro-2-ethoxy 2H-pyran. This impurity component of the glutaraldehyde biological or technical grades has an UV absorption peak at 235nm. The second compound is a white amorphous solid which is insoluble in water and has a melting point of 80-82°C. Initial chemical analysis indicates that this compound is an aldol condensation product(s) of glutaraldehyde.

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Amino Acid Compositions of Common Edible Mushrooms

Journal for the Integrated Study of Dietary Habits ◽

10.2740/jisdh.6.3_34 ◽

1995 ◽

Vol 6 (3) ◽

pp. 34-37

Author(s):

Shinobu Fujihara ◽

Atsuko Kasuga ◽

Tatsuyuki Sugahara ◽

Yasuo Aoyagi

Keyword(s):

Amino Acid ◽

Edible Mushrooms ◽

Amino Acid Compositions

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Simultaneously Identify Three Different Attributes of Proteins by Fusing their Three Different Modes of Chou's Pseudo Amino Acid Compositions

Protein and Peptide Letters ◽

10.2174/0929866522666150209151344 ◽

2015 ◽

Vol 22 (6) ◽

pp. 547-556 ◽

Cited By ~ 7

Author(s):

Chao Huang ◽

Jing-Qi Yuan

Keyword(s):

Amino Acid ◽

Amino Acid Compositions

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A Brief Review on Software Implementations and Algorithm Enhancements of Chou's Pseudo-Amino Acid Compositions

Current Proteomics ◽

10.2174/157016461302160514003628 ◽

2016 ◽

Vol 13 (2) ◽

pp. 105-112 ◽

Cited By ~ 1

Author(s):

Pu-Feng Du

Keyword(s):

Amino Acid ◽

Amino Acid Compositions ◽

Software Implementations

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Small Mass but Strong Information: Diagnostic Ions Provide Crucial Clues to Correctly Identify Histone Lysine Modifications

Proteomes ◽

10.3390/proteomes9020018 ◽

2021 ◽

Vol 9 (2) ◽

pp. 18

Author(s):

Alaa Hseiky ◽

Marion Crespo ◽

Sylvie Kieffer-Jaquinod ◽

François Fenaille ◽

Delphine Pflieger

Keyword(s):

Amino Acid ◽

Small Mass ◽

Mass Region ◽

Amino Acid Sequences ◽

Lysine Modification ◽

Lysine Residues ◽

Two Factors ◽

Low Mass ◽

Diagnostic Ions

(1) Background: The proteomic analysis of histones constitutes a delicate task due to the combination of two factors: slight variations in the amino acid sequences of variants and the multiplicity of post-translational modifications (PTMs), particularly those occurring on lysine residues. (2) Methods: To dissect the relationship between both aspects, we carefully evaluated PTM identification on lysine 27 from histone H3 (H3K27) and the artefactual chemical modifications that may lead to erroneous PTM determination. H3K27 is a particularly interesting example because it can bear a range of PTMs and it sits nearby residues 29 and 31 that vary between H3 sequence variants. We discuss how the retention times, neutral losses and immonium/diagnostic ions observed in the MS/MS spectra of peptides bearing modified lysines detectable in the low-mass region might help validate the identification of modified sequences. (3) Results: Diagnostic ions carry key information, thereby avoiding potential mis-identifications due to either isobaric PTM combinations or isobaric amino acid-PTM combinations. This also includes cases where chemical formylation or acetylation of peptide N-termini artefactually occurs during sample processing or simply in the timeframe of LC-MS/MS analysis. Finally, in the very subtle case of positional isomers possibly corresponding to a given mass of lysine modification, the immonium and diagnostic ions may allow the identification of the in vivo structure.

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Cross-linking of the electron-transfer flavoprotein to electron-transfer flavoprotein-ubiquinone oxidoreductase with heterobifunctional reagents

Biochemical Journal ◽

10.1042/bj2550869 ◽

1988 ◽

Vol 255 (3) ◽

pp. 869-876 ◽

Cited By ~ 14

Author(s):

D J Steenkamp

Keyword(s):

Electron Transfer ◽

Small Subunit ◽

Cross Linking ◽

Minor Effect ◽

Electron Transfer Flavoprotein ◽

Ubiquinone Oxidoreductase ◽

Lysine Residues ◽

Cross Links ◽

A Minor ◽

Chemical Cross Linking

The mitochondrial electron-transfer flavoprotein (ETF) is a heterodimer containing only one FAD. In previous work on the structure-function relationships of ETF, its interaction with the general acyl-CoA dehydrogenase (GAD) was studied by chemical cross-linking with heterobifunctional reagents [D. J. Steenkamp (1987) Biochem. J. 243, 519-524]. GAD whose lysine residues were substituted with 3-(2-pyridyldithio)propionyl groups was preferentially cross-linked to the small subunit of ETF, the lysine residues of which had been substituted with 4-mercaptobutyramidine (MBA) groups. This work was extended to the interaction of ETF with ETF-ubiquinone oxidoreductase (ETF-Q ox). ETF-Q ox was partially inactivated by modification with N-succinimidyl 3-(2-pyridyldithio)propionate to introduce pyridyl disulphide structures. A similar modification of ETF caused a large increase in the apparent Michaelis constant of ETF-Q ox for modified ETF owing to the loss of positive charge on some critical lysines of ETF. When ETF-Q ox was modified with 2-iminothiolane to introduce 4-mercaptobutyramidine groups, only a minor effect on the activity of the enzyme was observed. To retain the positive charges on the lysine residues of ETF, pyridyl disulphide structures were introduced by treating ETF with 2-iminothiolane in the presence of 2,2′-dithiodipyridyl. The electron-transfer activity of the resultant ETF preparation containing 4-(2-pyridyldithio)butyramidine (PDBA) groups was only slightly affected. When ETF-Q ox substituted with MBA groups was mixed with ETF bearing PDBA groups, at least 70% of the cross-links formed between the two proteins were between the small subunit of ETF and ETF-Q ox. ETF-Q ox, therefore, interacts predominantly with the same subunit of ETF as GAD. Variables which affect the selectivity of ETF-Q ox cross-linking to the subunits of ETF are considered.

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