In:
European Journal of Biochemistry, Wiley, Vol. 21, No. 4 ( 1971-08), p. 507-516
Abstract:
Elastin was prepared from calf ligamentum nuchae with several methods using the following solvents for the extraction of extraneous (non‐elastin) proteins: 0.1 N NaOH at 100 °C, 88% formic acid at 45 °C, 70% trichloracetic acid at +4 °C, 5 M guanidine HCl with a thiol reagent and autoclaving in water. All elastin samples contained small amounts of carbohydrate. Electron microscopy showed the presence in all samples of electron‐translucent lamellae and osmiophilic uranyl‐lead stainable “microfibrillar” elements. The osmiophilic “microfibrils” decreased strongly in the elastin preparations after extraction with 8 M urea–0.1 M 2‐mercaptoethanol, 5 M guanidine–0.05 M dithiothreitol or 0.1 M Na 2 SO 3 . These solvents extracted a significant proportion of the hexose content of the elastin samples with only 6–7% of their protein content. Similar results were obtained with chymotrypsin digestion although this enzyme acts less selectively than the above mentioned solvents and degrades elastin also. When 125 I‐labelled elastin was used for extraction with 8 M urea–0.1 M mercaptoethanol the extracted glycopeptides had a significantly higher specific activity than the residual elastin. These results suggest that the microfibrillar elements are derived from or are identical with the structural glycoproteins which were extracted from elastin‐rich tissues by identical procedures [12]. The presence of glycoprotein in varying proportions in purified elastin preparations can explain the variation of its amino acid content (ratio of polar to non‐polar amino acids) with age or in certain pathological conditions (atheromatosis, emphysema) and some of its immunochemical properties (cross reactions with structural glycoproteins).
Type of Medium:
Online Resource
ISSN:
0014-2956
,
1432-1033
DOI:
10.1111/ejb.1971.21.issue-4
DOI:
10.1111/j.1432-1033.1971.tb01496.x
Language:
English
Publisher:
Wiley
Publication Date:
1971
detail.hit.zdb_id:
1398347-7
detail.hit.zdb_id:
2172518-4
SSG:
12
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