Melting Equilibrium for Collagen Fibers under Stress. Elasticity in the Amorphous State<sup>1</sup>

Flory, Paul J.; Spurr, O. K.

doi:10.1021/ja01467a013

Cited by 89 publications

(23 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The values of AEgG obtained are presented in the last column of Table 6. The denaturation enthalpy values determined by McClain and Wiley [25] were in good agreement with the value of AH = 4.8 kJ mol-' reported by Flory and Spurr [45] for rat tail tendon collagen, and the value of AH = 4.6 kJ mol-' determined by Kuntzel and Doehner [46] for bovine hide powder. Harrington and Rao [47] derived values of A H = 4.66 kJ mol-' for rat skin and 4.74 kJ mol-' for cod skin.…”

Section: Unfolding Of'the Triple Helixsupporting

confidence: 87%

Physico‐chemical studies of micelle formation on sepia cartilage collagen solutions in acetate buffer and its interaction with ionic and nonionic micelles

Mandal

Ramesh

Dhar

1987

European Journal of Biochemistry

View full text Add to dashboard Cite

Sepia cartilage collagen (pepsin-extracted) in acetate buffer (pH = 2.98) forms micelles at a particular concentration below which they do not normally form. The critical micelle concentration (cmc) of the collagen was determined in buffer as well as in SDS, cetyltrimethylammonium bromide (CTAB) and Tween-80 micellar environments at different temperatures. Mutual interaction of collagen micelles with the ionic and nonionic micelles through the formation of the mixed micelle concept has also been found. The cmc of collagen decreased in the presence of SDS and Tween-80 micelles whereas it increased in the presence of CTAB micelles. This clearly suggests that the micelle formation of collagen is facilitated by the presence of SDS and Tween-80 and hindered by CTAB micelles. The various thermodynamic parameters were estimated from viscosity measurements and the transfer of collagen into the micelles of various surfactants and the reverse phenomenon was analyzed. This analysis has also been modelled conceptually as a different phase and the results have supported the above phenomenon. Our thermodynamic results are also able to predict the exact denaturation temperature as well as the structural order of water in the collagen in various environments. The hydrated volumes, Vh, of collagen in the above environments and intrinsic viscosity were also calculated. The low intrinsic viscosity, [?I, of collagen in an SDS environment compared to buffer and other surfactant environments suggested more workable systems in cosmetic and dermatological skin care preparations. The one and two-hydrogen-bonded models of this collagen in various environments have been analyzed. The calculated thermodynamic parameters varied with the concentration of collagen. The change of thermodynamic parameters from coil-coil to random-coil conformation upon denaturation of collagen were calculated from the amount of proline and hydroxyproline residues and compared with viscometric results. Thermodynamic results suggest that the stability of the collagen in the additive environments is in the following order: SDS > Tween-80 > buffer > CTAB.It is well known that the structure of water is important for interactions between proteins and membrane transport phenomena. These interactions are difficult to study due to the fact that the exact shapes, sizes and structure of the proteins are not clearly known. A favourable exception is collagen, consisting of triple-stranded helices which can be regarded as rigid rods. According to X-ray diffraction patterns the rods are packed in a complex lattice [l]. The important features are that the rods are aligned along the fiber axis and that the lattice expands [2] commensurate with the water content. The studies from various sources have indicated that the structure of water absorbed in collagen is different from that of water in bulk. Broad-line NMR measurements [3 -61 have shown two absorption lines instead of one. This may be the reason that the water molecules in collagen do not rotating isotropically. Moreover,...

show abstract

Section: Unfolding Of'the Triple Helixsupporting

confidence: 87%

Physico‐chemical studies of micelle formation on sepia cartilage collagen solutions in acetate buffer and its interaction with ionic and nonionic micelles

Mandal

Ramesh

Dhar

1987

European Journal of Biochemistry

View full text Add to dashboard Cite

show abstract

“…(1) is 60.5 • C. This coincides with the general understanding that the denaturation temperature of collagen fiber is 60 • C [9,10]. Also, our adhesion temperature is lower than electrosurgical vessel-sealing systems in which tissue needs to be heated between 70 and 95 • C [7,11,12]. The proposed method can be used to adhere tissues with less thermal damage.…”

Section: Comparison Of Tissue Damage With Conventional Methods and Effsupporting

confidence: 76%

Development of tissue adhesion method using integrated low-level energies

Katoh¹,

Masuzawa²,

Ozeki³

et al. 2010

Medical Engineering & Physics

View full text Add to dashboard Cite

“…Nonetheless, decreases in configurational entropy due to static load was found to reduce enzymolysis by collagenases [26][27][28][29] and increase thermal stability [30][31][32] significantly, presumably via reduction of configurational/conformational entropy of the collagen molecules. Clearly, increased proteolysis 5 is mirrored by reduced thermal stability of the collagen molecules.…”

Section: Discussionmentioning

confidence: 96%

Mechanical overload decreases the thermal stability of collagen in an in vitro tensile overload tendon model

Willett

Labow

Lee

2008

Journal Orthopaedic Research

View full text Add to dashboard Cite

Musculoskeletal soft tissue injuries are very common, yet poorly understood. We investigated molecular-level changes in collagen caused by tensile overload of bovine tail tendons in vitro. Previous investigators concluded that tensile tendon rupture resulted in collagen denaturation, but our study suggests otherwise. Based on contemporary collagen biophysics, we hypothesized that tensile overload would lead to reduced thermal stability without change in the nativity of the molecular conformation. The thermal behavior of collagen from tail tendons ruptured in vitro at two strain rates (0.01 s(-1) and 10 s(-1)) was measured by differential scanning calorimetry (DSC). The 1,000-fold difference in strain rate was used since molecular mechanisms that determine mechanical behavior are thought to be strain rate-dependent. DSC revealed that the collagen in tensile overloaded tendons was less thermally stable by 3 degrees to 5 degrees C relative to undamaged controls and was not denatured since there was no change in enthalpy of denaturation. The decrease in thermal stability occurred throughout the overloaded regions, independent of rupture site, and was greater in specimens ruptured at the lower strain rate. The deformation mechanism apparently involves disruption of the lattice structure of the collagen fibrils and greatly increases the molecular freedom of the collagen molecules, leading to reduced thermal molecular stability and the previously reported increased proteolysis. This has important implications for understanding soft tissue injuries, disease etiology and treatment, and for developing tissue engineered products with improved durability.

show abstract

Melting Equilibrium for Collagen Fibers under Stress. Elasticity in the Amorphous State¹

Cited by 89 publications

References 0 publications

Physico‐chemical studies of micelle formation on sepia cartilage collagen solutions in acetate buffer and its interaction with ionic and nonionic micelles

Physico‐chemical studies of micelle formation on sepia cartilage collagen solutions in acetate buffer and its interaction with ionic and nonionic micelles

Development of tissue adhesion method using integrated low-level energies

Mechanical overload decreases the thermal stability of collagen in an in vitro tensile overload tendon model

Contact Info

Product

Resources

About

Melting Equilibrium for Collagen Fibers under Stress. Elasticity in the Amorphous State1

Cited by 89 publications

References 0 publications

Physico‐chemical studies of micelle formation on sepia cartilage collagen solutions in acetate buffer and its interaction with ionic and nonionic micelles

Physico‐chemical studies of micelle formation on sepia cartilage collagen solutions in acetate buffer and its interaction with ionic and nonionic micelles

Development of tissue adhesion method using integrated low-level energies

Mechanical overload decreases the thermal stability of collagen in an in vitro tensile overload tendon model

Contact Info

Product

Resources

About

Melting Equilibrium for Collagen Fibers under Stress. Elasticity in the Amorphous State¹