Fibrous proteins made by α-helices, one of the most elementary protein secondary structures, have various mechanical roles in a sub cellular environment. An α-helix is wound in a right-handed fashion due to hydrogen bonding between the C=O and the N-H atoms across every i and i+4th residues in the polypeptide chain. Previous approaches characterizing mechanical properties of α-helices treated them as homogenous and linear elastic rods. Stiffness is typically expressed in terms of persistence length lp (∼100nm from Kb∼3×10−28 Nm2, lp = Kb/kT: Kb, the bending stiffness, k the Boltzmann constant and T = 300 K, the temperature) [1–3]. In this study, we show that bending stiffness depends on the length of the filament, due to inherent non-bonded attractions. In particular, non-bonded attraction introduces a new length scale, critical buckling length, beyond which the filament can no longer remain linearly elastic. These results suggest that non-bonded attractions can significantly affect elastic properties of biofilament systems such as the cytoskeleton. Furthermore, we find that while elasticity of a single α-helix is largely independent of its amino acid sequence, α-helical coiled-coils have stronger sequence dependence, and in the case of tropomyosin molecule, we find regional variations in the flexibility which may have functional implications in its actin binding properties and muscle contraction.
Skip Nav Destination
ASME 2009 Summer Bioengineering Conference
June 17–21, 2009
Lake Tahoe, California, USA
Conference Sponsors:
- Bioengineering Division
ISBN:
978-0-7918-4891-3
PROCEEDINGS PAPER
Length and Sequence Dependence of the Elasticity of Alpha Helices and Coiled-Coils Available to Purchase
Sirish Kaushik Lakkaraju,
Sirish Kaushik Lakkaraju
Texas A&M University, College Station, TX
Search for other works by this author on:
Wonmuk Hwang
Wonmuk Hwang
Texas A&M University, College Station, TX
Search for other works by this author on:
Sirish Kaushik Lakkaraju
Texas A&M University, College Station, TX
Wonmuk Hwang
Texas A&M University, College Station, TX
Paper No:
SBC2009-206252, pp. 547-548; 2 pages
Published Online:
July 19, 2013
Citation
Lakkaraju, SK, & Hwang, W. "Length and Sequence Dependence of the Elasticity of Alpha Helices and Coiled-Coils." Proceedings of the ASME 2009 Summer Bioengineering Conference. ASME 2009 Summer Bioengineering Conference, Parts A and B. Lake Tahoe, California, USA. June 17–21, 2009. pp. 547-548. ASME. https://doi.org/10.1115/SBC2009-206252
Download citation file:
6
Views
Related Proceedings Papers
Related Articles
Manipulation of Remodeling Pathways to Enhance the Mechanical Properties of a Tissue Engineered Blood Vessel
J Biomech Eng (December,2002)
Mechanics of Indentation into Micro- and Nanoscale Forests of Tubes, Rods, or Pillars
J. Eng. Mater. Technol (January,2011)
Snap Buckling in Overhand Knots
J. Appl. Mech (April,2023)
Related Chapters
Conclusions
Chitosan and Its Derivatives as Promising Drug Delivery Carriers
Novel and Efficient Mathematical and Computational Methods for the Analysis and Architecting of Ultralight Cellular Materials and their Macrostructural Responses
Advances in Computers and Information in Engineering Research, Volume 2
Clinical issues and experience
Mechanical Blood Trauma in Circulatory-Assist Devices