Amino Acid Composition Of Collagen Research Articles

Improved quality control criteria for stable carbon and nitrogen isotope measurements of ancient bone collagen

The carbon (δ13C) and nitrogen (δ15N) isotopic compositions of bone and tooth collagen provide a powerful tool for studying past biological, environmental, and cultural phenomena. Collagen has a well-understood chemical composition that has enabled the development of invaluable quality control (QC) criteria for isotopic data – something that is extremely rare among biogeochemical research on ancient biomolecules as a whole. The most important of these collagen QC criteria is atomic C:N ratio (ratio of carbon to nitrogen atoms), which provides an indicator of the extent to which the amount of carbon and nitrogen present in a sample matches the known composition of pure collagen, thereby indicating whether contamination or diagenesis may be influencing a sample's isotopic compositions. We present a model describing the relationship between the carbon and nitrogen isotopic and elemental compositions that accounts for the isotopic composition of the endogenous collagen and exogenous contaminants as well as taxon-specific information about the collagen's amino acid composition. In some cases the traditional C:N QC parameters are applicable, while in others they can result in the inclusion of unreliable (altered) isotopic data primarily due to contamination from humic substances. Using new and previously published data on taxa commonly encountered in ancient studies, we further illustrate how using traditional C:N QC parameters may lead to the inclusion of altered isotopic compositions in real archaeological and paleontological scenarios. We argue that the traditional ‘one size fits all’ approach to the C:N QC criterion should be avoided and we outline new collagen QC criteria specific to certain taxa and environments on the basis of the results of our model. These revised criteria will help to improve the interpretation of isotopic data by more accurately identifying samples with isotopic compositions altered by contamination.

Mapping the Minimal Promoter Sequence for Human Prolidase (Peptidase D; PEPD‐ gene)

Collagen, the most abundant protein in humans, is the primary component of the extracellular matrix. Collagen is also a critical reservoir of proline that, along with hydroxyproline, comprise one‐fourth of the amino acid composition of collagen. During collagen turnover, sequential action of matrix metalloproteinases and peptidases convert collagen into dipeptides. In the subsequent final rate‐limiting step, prolidase (PEPD) hydrolyzes dipeptides containing C‐terminal proline or hydroxyproline into the constituent amino acids, which are then recycled towards collagen synthesis. Due to its critical role in collagen turnover and protein metabolism, prolidase is a key player in several physiological and pathological processes, including wound healing, cell proliferation, inflammation, and carcinogenesis. Consequently, alterations in prolidase expression can profoundly affect normal physiological processes and cause pathological changes. The goal of this study is to narrow down such knowledge gaps, especially, in our understanding of the regulation of PEPD transcription. First, towards determining a functionally active promoter region of PEPD (PEPDp), we cloned a 1587 base pair (bp) DNA region—spanning 1537 bp upstream, and 50 bp downstream, of the transcription start site (TSS)—of PEPD gene into a firefly luciferase reporter plasmid. We confirmed that the PEPDp is functionally active by demonstrating its ability to robustly drive the luciferase expression in the HEK293T cell line. Second, we sought to determine the minimal region of PEPDp that is sufficient and necessary to drive gene expression. We subcloned two progressively shorter deletion fragments of PEPDp—537 bp and 387 bp long into the firefly luciferase reporter system and then compared their promoter activity with that of the full‐length PEPDp. Our findings thus indicate that the lack of any cancellation in the promoter activity of the PEPDp deletion fragments points out that the functionally active region of PEPDp spans ~350 bp upstream and 50 bp downstream of the transcriptional start site (TSS), thereby advancing our knowledge of the molecular mechanisms regulating prolidase expression.Support or Funding InformationThis work is partly supported by National Institutes of Health (NIH) Grants DA037779 and MD007586 (to Jui Pandhare) and DA024558, DA30896, DA033892, DA021471, AI22960 and MD007586 (to Chandravanu Dash). Ireti Eni‐aganga is supported by RISE Grant. The work is also supported by the RCMI Grant G12MD007586, the Vanderbilt CTSA Grant UL1RR024975, the Meharry Translational Research Center (MeTRC) CTSA grant (U54 RR026140 from NCRR/NIH, the U54 Grant MD007593 from NIMHD/NIH, and the Tennessee Center for AIDS Research (P30 AI110527).

Diabetes and Collagen: Interrelations

This review summarizes information on interrelations between diabetes development and collagen metabolism and structure. The growing global problem of diabetes requires the search for new strategies of its complications correction. Among them collagen structure violations and/or its impaired metabolism most often lead to profound disability. Even after several decades of intense studies, pathophysiological mechanisms underlying collagen changes in diabetes mellitus are still not well clear. The main complication is that not only diabetes cause changes in collagen metabolism and structure. Collagens via some mechanisms also may regulate glucose homeostasis, both directly and indirectly. The author also presented the results of own studies on bone and skin type I collagen amino acid composition changes with diabetes. Deepening our understanding of collagen metabolism and diabetes interrelations allows us to optimize approaches to overcome the collagen-mediated consequences of this disease. Recently, it has been clearly demonstrated that use of only antidiabetic agents cannot fully correct such violations. Preparations on the base of flavonoids, collagens and amino acids could be considered as perspective directions in this area of drug development.

Amino acid composition in determination of collagen origin and assessment of physical factors effects

The amino acid composition of collagen is a characteristic feature of this protein. Collagen, irrespective of its origin, contains 19 amino acids, including hydroxyproline which does not occur in other proteins. Its atypical amino acid composition is characterized by high content of proline and glycine, as well as the absence of cysteine.This paper shows the comparison of qualitative composition of amino acids of fish skin (FS) collagen, bovine Achilles tendon (BAT) collagen, and bone collagen. Results demonstrate that FS collagen as well as BAT collagen contains no cysteine and significantly different amount of hydroxyproline. In BAT collagen hydroxyproline content is 30% higher than hydroxyproline content of FS collagen. In bone collagen the amount of hydroxyproline is two times more than in FS collagen.Furthermore, it is shown that sensitivity to radiation of individual amino acids varies and depends on the absorbed dose of ionizing radiation. The changes observed in the amino acid composition become very intense for the doses of 500kGy and 1000kGy.

Transforming Growth Factor (TGF)-β Promotes de Novo Serine Synthesis for Collagen Production

TGF-β promotes excessive collagen deposition in fibrotic diseases such as idiopathic pulmonary fibrosis (IPF). The amino acid composition of collagen is unique due to its high (33%) glycine content. Here, we report that TGF-β induces expression of glycolytic genes and increases glycolytic flux. TGF-β also induces the expression of the enzymes of the de novo serine synthesis pathway (phosphoglycerate dehydrogenase (PHGDH), phosphoserine aminotransferase 1 (PSAT1), and phosphoserine phosphatase (PSPH)) and de novo glycine synthesis (serine hydroxymethyltransferase 2 (SHMT2)). Studies in fibroblasts with genetic attenuation of PHGDH or SHMT2 and pharmacologic inhibition of PHGDH showed that these enzymes are required for collagen synthesis. Furthermore, metabolic labeling experiments demonstrated carbon from glucose incorporated into collagen. Lungs from humans with IPF demonstrated increased expression of PHGDH and SHMT2. These results indicate that the de novo serine synthesis pathway is necessary for TGF-β-induced collagen production and suggest that this pathway may be a therapeutic target for treatment of fibrotic diseases including IPF.

Adaptive amino acid composition in collagens of parasitic nematodes

Amino acid composition was analyzed in the glycine-rich repeat region of 306 collagens belonging to three major families of collagens from both parasitic and free-living nematodes. The collagens of parasitic species showed a tendency toward decreased usage of the hydrophilic residues A, D, and Q and increased usage of the hydrophobic resides I, L, and M; and this trend was seen in parasitic species of both the order Rhabdita and the order Spirurida. The amino acid composition of collagens of parasitic Rhabdita thus tended to resemble those of Spirurida more than that of free-living Rhabdita, suggesting an association between amino acid composition and a parasitic lifestyle. Computer predictions suggested that the more hydrophobic amino acid composition was associated with a reduction of the propensity towards B-cell epitope formation, suggesting that evasion of host immune responses may be a major selective factor responsible for the parasite-specific trend in collagen amino acid composition.

Natural Peptides with Potential Applications in Drug Development, Diagnosis, and/or Biotechnology

Natural Peptides with Potential Applications in Drug Development, Diagnosis, and/or Biotechnology

Fish bone chemistry and ultrastructure: implications for taphonomy and stable isotope analysis

This paper reviews the ultrastructure and chemistry of fish bone, with an emphasis on zooarchaeology and stable isotope analysis. On the basis of the chemical composition of the collagen and the relationships between the collagen and mineral phases, fish bone is more susceptible to biotic and abiotic degradation than mammalian bone and is therefore less likely to be recovered in archaeological deposits. The amino acid composition of fish bone differs from that of mammals, most notably with respect to hydroxyproline content. The C:N ratio of fish collagen is, however, very similar and slightly lower than mammalian collagen, and thus the traditional range of acceptable C:N ratios for archaeological bone collagen (2.9–3.6) should not be shifted or extended for fish on the basis of the amino acid composition of collagen. An extensive survey of published archaeological bone collagen C:N ratios demonstrates that fish collagen from archaeological contexts tends to have significantly higher C:N ratios than mammalian collagen. The elevated C:N ratios in fish bone collagen may be the result of abiotic degradation processes that occur within the bone after death, the presence of exogenous humic contaminants, or endogenous lipid contaminants.

PP-197 Pyrazinamide-mediated alterations in male rats DNA fragmentation processes, bone collagen amino acid composition, reproductive capability and posterity antenatal and postnatal development

PP-197 Pyrazinamide-mediated alterations in male rats DNA fragmentation processes, bone collagen amino acid composition, reproductive capability and posterity antenatal and postnatal development

Isolation and characterisation of collagens from the skin of largefin longbarbel catfish (Mystus macropterus)

Abstract Acid-soluble collagen (ASC) and pepsin-soluble collagen (PSC) were extracted from the skin of largefin longbarbel catfish ( Mystus macropterus ) with yields of 16.8% and 28.0%, respectively, on the basis of dry weight. Both ASC and PSC contained α1 and α2 chains and the amino acid composition of collagen was close to that of calf skin type І collagen. The intrinsic viscosities of ASC and PSC were 14.9 dl/g and 14.5 dl/g, respectively. Similar ultraviolet and FTIR spectra of ASC and PSC were observed. However, peptide maps of ASC and PSC, hydrolysed by trypsin, revealed some differences in primary structures between the two fractions. Denaturation temperatures of ASC and PSC were 32.1 °C and 31.6 °C, respectively. The higher T m showed that it is possible to use largefin longbarbel catfish skin collagen as an alternative source of vertebrate collagens for industrial purposes.

The biochemical composition of haemodynamically stressed vascular tissue III. The collagen composition of experimental arteriovenous fistulae

The external jugular vein and the common carotid artery were anastomosed in 8 sheep. Morphological changes similar to those observed in human atherosclerosis are produced particularly in the venous tissue. There is a significant increase in the collagen content of the dilated mid-segment of the experimental vein. Also there is a positive correlation between post-operative age and the amount of collagen, especially in the distal region of the artery and in the proximal and middle regions of the vein. In both the control and experimental veins the amino acid composition of collagen was very similar. However, the arterial preparations did not exhibit the same degree of purity. Most of the collagen was the type I variant (approx. 80% in arteries and 70% in veins). In the sham-operated veins about 30% of the collagen was type III but it was nearer 17% in the control arteries. Whilst experimental and control arteries had similar proportions of type III collagen, there was a 30% reduction in the experimental veins. Although there was no significant correlation between the proportion of any of the genetic types of collagen and the post-operative age of the animals, there was a strong correlation for the increment in type I in all regions of the experimental vein as a function of time.

Connective tissue metabolism in muscular dystrophy. Amino acid composition of native types I, III, IV and V collagen isolated from the gastrocnemius muscle of embryonic chickens with genetic muscular dystrophy

1. 1. The amino acid composition data on types I, III, IV and V collagen isolated from embryonic dystrophic skeletal muscle strongly indicate that alterations in collagen synthesis occur in intramuscular connective tissue of developing muscles in embryonic dystrophic chickens. 2. 2. The changes observed in the amino acid composition of dystrophic collagen were: (a) a selective removal of polar amino acids and substitution with non-polar amino acids; (b) significant decreases in basic (lysine, hydroxylysine and arginine) and hydroxylated (4-hydroxyproline and hydroxylysine) amino acids; and (c) significant increases in the amounts of glycine, proline and alanine. 3. 3. The amino acid substitutions suggest a genetic alteration in the collagen synthesizing process and a change in its structure. 4. 4. The variations in amino acid composition of collagen from dystrophic chickens could give rise to a decrease in both inter- and intramolecular cross-linking, thus decreasing the stability and functionality of newly formed collagen fibrils. 5. 5. The differences associated with the dystrophic collagen reported in this study are probably due to the differences in primary structure in terms of amino acid sequence rather than post-translational modifications. 6. 6. The structural differences noted would also lead to an alteration of the role collagen plays in regulating the differentiation of developing muscles. 7. 7. The changes in amino acid structure strongly suggest that the ‘collagen’ formed by dystrophic chickens should be considered a collagen-like protein or ‘collagenoid’.

水産動物のＬ‐アスコルビン酸に関する生化学的研究 ＸＶ アスコルビン酸欠乏ニジマスにおけるヒドロキシプロリン含量の低い“異常コラーゲン”の蓄積

Amino acid compositions of collagens from the skin and vertebrae were determined in rainbow trout which had been fed with purified diets containing different amounts of L-ascorbic acid (AsA) for 11 weeks. Hydroxyproline contents of collagens from the skin and vertebrae were comparatively low in the groups receiving 0 or 2mg of AsA per 100g of diet, when compared with the control fish receiving 200mg of AsA per 100g of diet. The dietary AsA levels had little effect on the hydroxylysine content of collagen. The thermal stability of the skin collagen was investigated using changes in viscosity. The viscosity of collagen solution was measured after keeping the sample for 30min at some fixed temperature between 5 and 25°C. The denaturation temperatures of collagens from the groups receiving 5 to 200mg of AsA per 100 g of diet were 18.1 to 18.3°C, whereas those of collagens from the groups receiving 0 and 2mg of AsA per 100g of diet were 16.6 and 17.1°C, respectively. The viscosities of collagens from the groups receiving 5 to 200mg of AsA per 100g of diet were not decreased markedly up to 15°C, whereas those of collagens from the groups receiving 0 and 2mg of AsA per 100g of diet were low around 10°C. These results indicate that an underhydroxylated thermally labile collagen is formed and accumulates in the tissues of the fish which are fed with an AsA-deficient diet.

Pepsin-solubilized collagen of human nucleus pulposus and annulus fibrosus

Human nucleus pulposus and annulus fibrosus, obtained at autopsy from patients 7–30 years of age, were extracted with 2 M guanidine HCl (pH 5.82) to remove proteoglycans, then stirred with pepsin in 0.5 M acetic acid, followed by three 24-h extractions with 1 M NaCl (pH 7.5) and one 24-h extraction with 2 M KSCN (potassium thiocyanate) (pH 7.2). Pepsin and NaCl solubilized an average of about 30% of nucleus pulposus collagen and 18% of annulus fibrosus collagen. KSCN extracted a further 34% of nucleus pulposus collagen and only 4% of annulus fibrosus collagen. CM-cellulose chromatography of nucleus and annulus collagen purified from the pepsin, NaCl and KSCN supernatants consistently revealed only one peak, always appearing slightly ahead of the α 1 position for rat tail tendon type I collagen. Polyacrylamide and SDS-gel electrophoresis consistently revealed only one band with the mobility of α 1 chains. Amino acid composition of collagen from nucleus and annulus is comparable to those of mammalian and avian cartilage type II collagen, and distinctly different from those of rat tail tendon and guinea pig skin type I collagens. Periodate oxidation of nucleus and annulus collagens showed that 81% and 67%, respectively, of the hydroxylysine residues survive treatment, compared to 71% for bovine articular cartilage collagen and 17% for guinea pig skin collagen. Total hexose analysis revealed 1.8 μM and 2.0 μM hexose per μM periodate-stable hydroxylysine in nucleus and annulus collagens, respectively. Ion exchange chromatography showed the presence of glucose and galactose in a ratio of 0.92:1 in nucleus collagen and 1.07:1 in annulus collagen. Pepsin-solubilized, NaCl-extracted collagen from nucleus and annulus formed native-type fibrils in vitro. The banding patterns of ATP-induced segment-long-spacing precipitates of nucleus and annulus collagens were identical to each other and indistinguishable from those of cartilage (type II) collagen, but distinctly different from those of rat tail tendon (type I) collagen. These data suggest that the collagen which can be extracted after limited pepsin attack of human nucleus and annulus is of the form [ α 1 ( II)] 3.

Effect of ascorbic acid on guinea pig skin collagen synthesis. II. Neutral and acid soluble collagens, mucopolysaccharides, and amino acid composition.

Scorbutic guinea pigs incorporated approximately 15% as much 3H-proline into total skin collagen as the positive controls and hydroxylated 66% as much of that incorporated. 35S-sulfate incorporation into skin acid mucopolysaccharides was decreased 50% in scorbutic animals. Amino acid composition of collagens was similar to that of other vertebrates.

The purification and amino acid composition of human uterus collagens, rheumatoid-arthritis-nodule collagen and ox tendon collagen.

Collagens and gelatins were isolated from human post-menopausal uterus, puerperal (post-partum) uterus, rheumatoid-arthritis-nodule and ox tendon. Different means of purifying collagen were studied and a method was devised that enables highly purified collagen to be obtained, even from the uterus. This method involves the use of a number of aqueous and organic extractants as well as digestion with elastase to eliminate elastin. The purity of the collagen preparations was assessed and they were used to study the amino acid composition of collagen. The amino acid compositions of all the collagens studied were similar to those of human bone and tendon collagen, but certain small differences were noted and are discussed. The soluble collagen extracted from some of the tissues was also studied.

Amino-acid composition of collagen isolated from the oral cavity of the sperm whale.

THE composition of collagen is known to vary between species and between different tissue sources of the same animal1. The amino-acid hydroxyproline is a characteristic amino-acid of collagen since it is found, to a limited extent, in only one other protein, elastin. The hydroxyproline content of collagen and gelatine isolated from fish is reported to vary from 9.2 to 10.3 per cent, whereas collagen and gelatine from mammalian sources vary from 13.0 to 14.4 per cent (by weight)2. While studying collagen from various mammalian sources, we determined the amino-acid content of collagen from the oral cavity of the sperm whale (Physeter catodon) for comparison with known mammalian and whale-skin values.

Metabolism of Collagen in Mammalian Tissues

The amino acid composition of collagen is described and the status of knowledge about the synthesis of its unique amino acids, hydroxyproline and hydroxylysine, presented. This is followed by a schematic overview of collagen metabolism. Scurvy and lathyrism, the only two abnormalities of collagen metabolism which can now be reasonably elucidated at a molecular level, are then discussed in some detail. The paper concludes by stressing the importance of recognizing the role of histoarchitecture and of interactions of collagen with other compounds when studying collagen or its metabolism in the whole animal.

The Structure Of Collagen And Gelatin

Publisher Summary This chapter reviews that collagen constitutes the major protein component of skin, bone, tendon, and all the other forms of connective tissue. An understanding of collagen seems to the clinician to be a necessary prerequisite to a rational attack on many and diverse connective tissue disorders currently lumped together as “collagen diseases.” The unusual amino acid composition of collagen had also been recognized for some time. One-third of the residues of all collagens seemed to be glycine, while about one-fourth were proline and hydroxyproline. However, the stereochemical consequences of the presence of these residues has only become clear as a result of the detailed studies of synthetic homo- and copolymers of glycine and proline. Consideration of such synthetic polypeptides as simplified models of certain features of collagen and gelatin has been extremely helpful in recent years, and constitutes the rationale for the inclusion of a section dealing specifically with these synthetic polypeptides in this chapter. It also reviews that the collagen ⇆ gelatin transformation in solution has been recognized as a reversible first-order phase transition, subject to the same physical laws which govern the crystalline ⇆ amorphous phase transitions observed in systems of linear polymers. The direct relationship between the transition in solution and the well-known thermal shrinkage phenomenon exhibited by collagen fibers has also been established.

水産皮革の理化学的研究-X

The Protein composition of skin which gives an essential knowledge for manufacturing leather or gelatin was studied with the shark skin, an important raw material of marine leather and fish gelatin. The results obtained can be summarized as follows; (1) The content of globulin-alubumin fraction in the skin of great blue shark(Prionace Glaucus) was somewhat higher than in cattle hide (Cf. Table 1). The mucoid content in the shark was 5-6 times as larg as that in cattle hide (Cf. Tablc 2). (2) The content of elastin in shark skin was higher than in cattle hide. The elastin content in the dorsal skin of great blue shark was smaller than in the ventral skin. The amount of elastin contained in the dorsal and ventral skins of blue shark (Isuropsis Glauca) was the same as in the ventral skins of great blue shark (Cf. Table 2 and 3). (3) It has been found that collagen contained in shark skin is only about 13% in contrast with that of cattle hide which was reported to be nearly 30% of the green hide. For this reason, shark skin is not supposed very suitable as a material for manufacturing gelatin. (4) The amino acid composition of collagen could not be found different between great blue shark and terrestial animal hide when tested after Van Slyke's method (C1. Table 6). It seems that the two-dimensional chromatography of hydrolyzate of shark skin-collagen presented the pattern resemble to that of cattle hide-gelatin (Cf. Figure 3).