Nanobiomechanics of proteins and biomembrane

Abstract

A review of the work done in the Laboratory of Biodynamics of Tokyo Institute of Technology in the last decade has been summarized in this article in relation to the results reported from other laboratories. The emphasis here is the application of nanomechanics based on the force mode of atomic force microscopy (AFM) to proteins and protein-based biological structures. Globular proteins were stretched in various ways to detect the localized rigidity inside of the molecule. When studied by this method, bovine carbonic anhydrase II (BCA II), calmodulin and OspA protein all showed the presence of localized rigid structures inside the molecules. Protein compression experiments were done on BCA II to obtain an estimate of the Young modulus and its change in the process of denaturation. Then, the AFM probe method was turned on to cell membranes and cytoplasmic components. Force curves accompanying the extraction process of membrane proteins from intact cells were analysed in relation to their interaction with the cytoskeletal components. By pushing the AFM probe further into the cytoplasm, mRNAs were recovered from a live cell with minimal damage, and multiplied using PCR technology for their identification. Altogether, the work introduced here forms the basis of nanomechanics of protein and protein-based biostructures and application of the nanomechanical technology to cell biology.

Compliance profile of the human cornea as measured by atomic force microscopy

“…(Alessandrini and Facci, 2005; Cohen and Bitler, 2008; Costa, 2003; Deniz et al, 2008; Ebner et al, 2008; Franz and Puech, 2008; Frederix et al, 2009; Gadegaard, 2006; Goksu et al, 2009; Haupt et al, 2006; Ikai, 2008; Kasas and Dietler, 2008; Morris et al, 1999; Muller, 2008; Muller and Dufrene, 2008; Noy, 2006; Parot et al, 2007; Radmacher, 2007; Ritort, 2006; Santos and Castanho, 2004; Seantier et al, 2008; Veerapandian and Yun, 2009; Withers and Aston, 2006; Wright and Armstrong, 2006; Zhu and Sun, 2006)…”

Microscopy of Model Membranes

“…After reaching the set force, the cantilever retracts. A force versus distance curve is generated for both the approach and retraction, and these curves are used to analyze mechanical properties like stiffness or adhesion of the material [61]. It has also been used to probe protein structure by mechanical unfolding [62].…”

Interaction of Serum Proteins with Hemodialysis Membrane: Comparison with De-adhesion Process of AFM Probe from Adhesive Tapes

“…The repulsive interaction deflects the cantilever upward whereas attractive interaction downward. Based on this simple principle, indentation of the sample surface or tensile stretching of polymer chains has been conducted both on biological and non-biological specimens [8][9][10][11]. In this paper, we adopted AFM to measure the force required to detach the cantilever tip from the sample surface after making a temporal contact between them.…”