X-ray diffraction by collagen tape shows that type I collagen fibrils need not have a three-dimensional lattice

1977 ◽  
Vol 77 (1) ◽  
pp. 335-339 ◽  
Author(s):  
David W.L. Hukins
Keyword(s):  
Type I Collagen ◽  
Three Dimensional ◽  
Collagen Fibrils ◽  
Type I ◽  
X Ray Diffraction ◽  
Dimensional Lattice ◽  
X Ray

A new model for packing of type-I collagen molecules in the native fibril

1981 ◽  
Vol 1 (10) ◽  
pp. 801-810 ◽  
Author(s):  
Karl A. Piez ◽  
Benes L. Trus
Keyword(s):  
Type I Collagen ◽  
Hexagonal Lattice ◽  
Three Dimensional ◽  
Equatorial Region ◽  
Type I ◽  
X Ray Diffraction ◽  
X Ray ◽  
Left Handed ◽  
Crystal Model ◽  
Collagen Molecules

A specific fibril model is presented consisting of bundles of five-stranded microfibrils, which are usually disordered (except axially) but under lateral compression become ordered. The features are as follows (where D = 234 residues or 67 nm): (1) D-staggered collagen molecules 4.5 D long in the helical microfibril have a left-handed supercoil with a pitch of 400–700 residues, but microfibrils need not have helical symmetry. (2) Straight-tilted 0.5-D overlap regions on a near-hexagonal lattice contribute the discrete x-ray diffraction reflections arising from lateral order, while the gap regions remain disordered. (3) The overlap regions are equivalent, but are crystallographically distinguished by systematic displacements from the near-hexagonal lattice. (4) The unit cell is the same as in a recently proposed three-dimensional crystal model, and calculated intensities in the equatorial region of the x-ray diffraction pattern agree with observed values.

scholarly journals Comparison of the Structural Characteristics of Native Collagen Fibrils Derived from Bovine Tendons Using Two Different Methods: Modified Acid-Solubilized and Pepsin-Aided Extraction

Materials ◽  
2020 ◽  
Vol 13 (2) ◽  
pp. 358 ◽  
Author(s):  
Haiyan Ju ◽  
Xiuying Liu ◽  
Gang Zhang ◽  
Dezheng Liu ◽  
Yongsheng Yang
Keyword(s):  
Type I Collagen ◽  
Structural Characteristics ◽  
Polyacrylamide Gel Electrophoresis ◽  
Sodium Dodecyl ◽  
Dry Weight ◽  
Collagen Fibrils ◽  
Type I ◽  
X Ray Diffraction ◽  
Aggregation Structure ◽  
Native Collagen

Native collagen fibrils (CF) were successfully extracted from bovine tendons using two different methods: modified acid-solubilized extraction for A-CF and pepsin-aided method for P-CF. The yields of A-CF and P-CF were up to 64.91% (±1.07% SD) and 56.78% (±1.22% SD) (dry weight basis), respectively. The analyses of both amino acid composition and sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) confirmed that A-CF and P-CF were type I collagen fibrils. Both A-CF and P-CF retained the intact crystallinity and integrity of type I collagen’s natural structure by FTIR spectra, circular dichroism spectroscopy (CD) and X-ray diffraction detection. The aggregation structures of A-CF and P-CF were displayed by UV–Vis. However, A-CF showed more intact aggregation structure than P-CF. Microstructure and D-periodicities of A-CF and P-CF were observed (SEM and TEM). The diameters of A-CF and P-CF are about 386 and 282 nm, respectively. Although both A-CF and P-CF were theoretically concordant with the Schmitt hypothesis, A-CF was of evener thickness and higher integrity in terms of aggregation structure than P-CF. Modified acid-solubilized method provides a potential non-enzyme alternative to extract native collagen fibrils with uniform thickness and integral aggregation structure.

scholarly journals Crystalline three-dimensional packing is a general characteristic of type I collagen fibrils

FEBS Letters ◽  
1980 ◽  
Vol 113 (2) ◽  
pp. 238-240 ◽  
Author(s):  
J.-C. Jésior ◽  
A. Miller ◽  
C. Berthet-Colominas
Keyword(s):  
Type I Collagen ◽  
Three Dimensional ◽  
General Characteristic ◽  
Collagen Fibrils ◽  
Type I

Heat Treatment Strengthens Human Dentin

2008 ◽  
Vol 87 (8) ◽  
pp. 762-766 ◽  
Author(s):  
M. Hayashi ◽  
E.V. Koychev ◽  
K. Okamura ◽  
A. Sugeta ◽  
C. Hongo ◽  
...  
Keyword(s):  
Heat Treatment ◽  
Stress Intensity ◽  
Type I Collagen ◽  
Type I ◽  
Third Molars ◽  
X Ray Diffraction ◽  
Intensity Factors ◽  
X Ray ◽  
Human Dentin ◽  
Triple Helices

The flexural strength of Type I collagen, the major organic component of human dentin, increases with heat. We hypothesized that human dentin can be strengthened by heating, which may help prevent fracture of non-vital teeth after restoration. Beam-shaped dentin specimens were obtained from the crowns of human third molars. The dentinal tubular orientations were arranged to run parallel or perpendicular to loading surfaces. The flexural and microtensile strengths of dentin in the parallel specimens were 2- to 2.4-fold greater after being heated between 110°C and 140°C for 1 hr. The stress intensity factors at fracture also increased after specimens were heated. The x-ray diffraction analyses suggested that shrinking of the lateral packing of the collagen triple-helices from 14 Å to 11 Å was the probable cause of the strengthening of heated dentin. We conclude that heat treatment strengthens human dentin.

scholarly journals X-ray diffraction studies of enkephalins. Crystal structure of [(4′-bromo) Phe4,Leu5]enkephalin

1984 ◽  
Vol 218 (3) ◽  
pp. 677-689 ◽  
Author(s):  
T Ishida ◽  
M Kenmotsu ◽  
Y Mino ◽  
M Inoue ◽  
T Fujiwara ◽  
...  
Keyword(s):  
Crystal Structure ◽  
Least Squares Method ◽  
Heavy Atom ◽  
Three Dimensional ◽  
Diffraction Method ◽  
Biologically Active ◽  
Type I ◽  
X Ray Diffraction ◽  
X Ray ◽  
Relationship Of

In order to investigate the structure-activity relationship of [Leu5]- and [Met5]enkephalins, [(4′-bromo)Phe4, Leu5]-, [(4′-bromo)Phe4, Met5]- and [Met5] enkephalins were synthesized and crystallized. The crystal structure of [(4′-bromo) Phe4, Leu5]- enkephalin was determined by X-ray diffraction method using the heavy atom method and refined to R = 0.092 by the least-squares method. The molecule in this crystal took essentially the same type I' beta-turn conformation found in [Leu5]enkephalin [Smith & Griffin (1978) Science 199, 1214-1216). On the other hand, the preliminary three-dimensional Patterson analyses showed that the most probable conformations of [(4′-bromo)Phe4,Met5]- and [Met5]enkephalins are both the dimeric extended forms. Based on these insights, the biologically active conformation of enkephalin was discussed in relation to the mu- and delta-receptors.

The Effects of Different Hydroxyapatite/TiO2 Composite Coatings on Protein Expression of Osteoblast

2009 ◽  
Vol 610-613 ◽  
pp. 1104-1108 ◽  
Author(s):  
Jian Ye Han ◽  
Zhen Tao Yu ◽  
Lian Zhou
Keyword(s):  
Protein Expression ◽  
Type I Collagen ◽  
Composite Coatings ◽  
Type I ◽  
X Ray Diffraction ◽  
Rt Pcr ◽  
Chain Reaction ◽  
Compound Formation ◽  
X Ray ◽  
Polymerase Chain

Hydroxyapatite/TiO2 composite material was coated onto Ti25Nb3Mo2Sn3Zr (TLM) alloy substrate. To study the effects of hydroxyapatite/TiO2 composite coatings on bone-related protein expression, the osteoblast were cultured with composite coatings for different times. The phase transformation and compound formation of the HA/TiO2 coatings were investigated using XRD (X-ray diffraction). The mRNA expression of Type I collagen, alkaline phosphatase (ALP) and osteocalcin were studied by RT-PCR (reverse transcriptional polymerase chain reaction). The titania delayed the crystallization of HA. The mRNA expressions of Type I collagen are decreased as the increasing of TiO2 percentage. The mRNA expressions of osteocalcin are approached. The ALP expression on H4 coating (HA/TiO2 mol ration is 5) after the osteoblast cultured with composite coating for 6 days is the highest. The increasing of TiO2 amount decreases the bioactivity of the composite coatings.

Isolation, ultrastructure, and partial characterization of collagen from the perineurium of the Florida lobster, Panulirus argus

1991 ◽  
Vol 69 (8) ◽  
pp. 531-536
Author(s):  
Roy J. Baerwald ◽  
Lura C. Williamson ◽  
E. Stevens ◽  
C. Rike ◽  
S. Trabanino ◽  
...  
Keyword(s):  
Amino Acid ◽  
Protein Content ◽  
Type I Collagen ◽  
Carbohydrate Content ◽  
Panulirus Argus ◽  
Computer Assisted ◽  
Type I ◽  
X Ray Diffraction ◽  
X Ray ◽  
Fibril Diameter

Highly concentrated extracellular filaments in the perineurium of the Florida spiny lobster, Panulirus argus, were isolated using ultracentrifugation and linear sucrose gradients. The pellet obtained was highly enriched for the filaments as observed by transmission electron microscopy. Fibril diameter and axial periodicity measurements were obtained from filaments positively and negatively stained with uranyl acetate. A period between 14.0 and 25.0 nm and an average fibril diameter of 15.0 nm were observed. The filaments proved resistant to solubilization by most conventional agents and by several collagenases. NaOH (0.1 M at 100 °C) safely dissolved the filaments for measurements of protein content by the Lowry method and carbohydrate content with anthrone reagent. These tests revealed a protein content of ≈ 84% and a high carbohydrate content of ≈ 15%. Polyacrylamide electrophoresis of an acid-pepsin filament extract revealed a highly concentrated band (approximately 100 000) corresponding to the α-1 and α-2 bands of vertebrate type I collagen. Wide angle X-ray diffraction yielded meridional reflections that confirmed the filaments as collagen when compared with mammalian collagen X-ray diffraction. The amino acid composition was determined with a computer-assisted Beckman amino acid analyzer, which showed a glycine content of 279 residues/1000. Hydroxylysine and hydroxyproline were present in lower concentrations than expected.Key words: perineurium, lobster, collagen, extracellular matrix.

HAp Protein Composites Formed by Hydrolysis of α-TCP

2005 ◽  
Vol 284-286 ◽  
pp. 39-42 ◽  
Author(s):  
Ahmed H. Touny ◽  
Paul W. Brown
Keyword(s):  
Type I Collagen ◽  
Isothermal Calorimetry ◽  
Protein Structures ◽  
Structural Proteins ◽  
Surrounding Tissue ◽  
Type I ◽  
X Ray Diffraction ◽  
X Ray ◽  
Hydrolysis Of ◽  
Aggressive Effect

Composite material composed of hydroxyapatite (HAp) and structural proteins, such as type I collagen or cross-linked gelatins, were synthesized at 37.4°C by hydrolysis of alpha tricalcium phosphate (α-TCP) in the presence of these protein structures. X-ray diffraction (XRD)and isothermal calorimetry were used as tools to evaluate the rate of HAp formation. Rates of HAp formation depend on protein structure. Gelatin enhances HAp formation while collagen delays it. Changes in pH during the hydrolysis α-TCP are unlikely to have an aggressive effect on the surrounding tissue. The presence of the protein improves the ductility of the HAp/protein composite but it decreases the tensile strength.

Sign in / Sign up

Export Citation Format

Share Document