Structure biomacromolecules

T Ichiye, RB Yelle, JB Koerner, PD Swartz, BW Beck. Molecular dynamics simulation studies of electron transfer properties of Ee-S proteins. Biomacromolecules Erom 3-D Structure to Applications. Hanford Symposium on Health and the Environment 34, Pasco, WA, 1995, pp 203-213. 

Alternatively, one interesting drug delivery technique exploits the active transport of certain naturally-occurring and relatively small biomacromolecules across the cellular membrane. For instance, the nuclear transcription activator protein (Tat) from HIV type 1 (HlV-1) is a 101-amino acid protein that must interact with a 59-base RNA stem-loop structure, called the traus-activation region (Tar) at the 5 end of all nascent HlV-1 mRNA molecules, in order for the vims to replicate. HIV-Tat is actively transported across the cell membrane, and localizes to the nucleus [28]. It has been found that the arginine-rich Tar-binding region of the Tat protein, residues 49-57 (Tat+9 57), is primarily responsible for this translocation activity [29]. 

Tamura A, Oishi M, Nagasaki Y (2009) Enhanced cytoplasmic delivery of siRNA using a stabilized polyion complex based on PEGylated nanogels with a cross-linked polyamine structure. Biomacromolecules 10 1818-1827... 

Adsorbents for biomacromolecules such as proteins have special properties. First, they need to have large pore sizes. A ratio of pore radius to molecule radius larger than 5 is desirable to prevent excessive diffusional hindrance (see Intraparticle Mass Transfer in this section). Thus, for typical proteins, pore radii need to be in excess of 10-15 nm. Second, functional groups for interactions with the protein are usually attached to the adsorbent backbone via a spacer arm to provide accessibility. Third, adsorbents based on hydrophilic structures are preferred to limit nonspecific interactions with the adsorbent backbone and prevent global unfolding or denaturation of the protein. Thus, if hydrophobic supports are used, their surfaces are usually rendered hydrophilic by incorporating hydrophilic coatings such as dextran or polyvinyl alcohol. Finally, materials stable in sodium hydroxide solutions (used for clean-in-place) are... 

Asakura, T., Ohgo, K., Ishida, T., Taddei, P., Monti, P., and Kishore, R. (2005). Possible implications of serine and tyrosine residues and intermolecular interactions on the appearance of silk I structure of Bombyx mod silk fibroin-derived synthetic peptides High-resolution 13C cross-polarization/magic-angle spinning NMR study. Biomacromolecules 6, 468-474. 

Dicko, C., Knight, D., Kenney, J. M., and Vollrath, F. (2004b). Secondary structures and conformational changes in flagelliform, cylindrical, major, and minor ampullate silk proteins. Temperature and concentration effects. Biomacromolecules 5, 2105-2115. 

Ha, S. W., Gracz, H. S., Tonelli, A. E., and Hudson, S. M. (2005). Structural study of irregular amino acid sequences in the heavy chain of Bombyx mori silk fibroin. Biomacromolecules 6, 2563-2569. 

Rossle, M., Panine, P., Urban, V. S., and Riekel, C. (2004). Structural evolution of regenerated silk fibroin under shear Combined wide- and small-angle x-ray scattering experiments using synchrotron radiation. Biopolymers 74, 316-327. Rousseau, M. E., Lefevre, T., Beaulieu, L., Asakura, T., and Pezolet, M. (2004). Study of protein conformation and orientation in silkworm and spider silk fibres using Raman microspectroscopy. Biomacromolecules 5, 2247-2257. 

Sirichaisit, J., Brookes, V. L., Young, R.J., and Vollrath, F. (2003). Analysis of structure/ property relationships in silkworm (Bombyx mori) and spider dragline (Nephila edulis) silks using Raman spectroscopy. Biomacromolecules 4, 387-394. 

Yang, Y. H., Shao, Z. Z., Chen, X., and Zhou, P. (2004). Optical spectroscopy to investigate the structure of regenerated Bombyx mori silk fibroin in solution. Biomacromolecules 5, 773-779. 

Yao, J. M., Nakazawa, Y., and Asakura, T. (2004). Structures of Bombyx mori and Samia cynthia ririni silk fibroins studied with solid-state NMR. Biomacromolecules 5, 680-688. 

Wangler C, Moldenhauer G, Saffrich R et al (2008) PAMAM structure-based multifunctional fluorescent conjugates for improved fluorescent labelling of biomacromolecules. Chem Eur J 14 8116-8130... 

The electrostatic motif represents an important recognition feature and also plays a part in determining the structure of biomacromolecules. 

While the structure of clusters responds to directionally specific electrostatic interactions, their stabilization energy reflects also the intervention of less specific dispersion interactions. This is, e.g., the case for stacked DNA base pairs. Stability of these pairs stems from dispersion energy while their structure is determined by dipole-dipole electrostatic interactions. Dispersion energy plays an important role in stabilizing clusters of biomacromolecules, where it may be the dominant attractive term. 

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