Document Detail


The binding of vitamin B12 to transcobalamin(II); structural considerations for bioconjugate design--a molecular dynamics study.
MedLine Citation:
PMID:  20379601     Owner:  NLM     Status:  MEDLINE    
Abstract/OtherAbstract:
As part of ongoing research into the use of vitamin B(12) (B(12); cobalamin; Cbl)-based bioconjugate approaches for the oral delivery of peptides/proteins, a molecular dynamics (MD) study of the binding of a cyanocobalamin-insulin (CN-Cbl-insulin) conjugate to human transcobalamin(II) (TCII) was recently reported that provides a qualitative picture of how the human insulin protein in its open "T-state" geometry affects CN-Cbl binding to TCII. This initial analysis revealed that the B22-B30 segment of the insulin B-chain acts as a long tether that connects the larger combined insulin A/B region to CN-Cbl when this conjugation is performed at the CN-Cbl ribose 5'-hydroxy position. The experimental support for this model of the binding interaction is provided by the consequences of the successful delivery of the CN-Cbl-insulin conjugate in the production of significantly decreased blood glucose levels in diabetic STZ-rat models. In efforts to provide a more detailed description of the (CN-Cbl)-TCII complex for modeling Cbl-based bioconjugate designs, the (CN-Cbl)-TCII system and a CN-Cbl conjugate incorporating a flexible tether composed of only the B22-B30 segment of human insulin have been examined by MD simulations. The implications of these simulations are discussed in terms of successful conjugate positioning on Cbl, especially when such sites are not apparent from the diffraction studies alone, and the possibilities, as yet not reported, for dual-tethered Cbl bioconjugates for multi-component drug delivery applications.
Authors:
Damian G Allis; Timothy J Fairchild; Robert P Doyle
Publication Detail:
Type:  Journal Article; Research Support, Non-U.S. Gov't     Date:  2010-04-08
Journal Detail:
Title:  Molecular bioSystems     Volume:  6     ISSN:  1742-2051     ISO Abbreviation:  Mol Biosyst     Publication Date:  2010 Sep 
Date Detail:
Created Date:  2010-08-16     Completed Date:  2010-12-07     Revised Date:  -    
Medline Journal Info:
Nlm Unique ID:  101251620     Medline TA:  Mol Biosyst     Country:  England    
Other Details:
Languages:  eng     Pagination:  1611-8     Citation Subset:  IM    
Affiliation:
Department of Chemistry, Syracuse University, Syracuse, NY 13244, USA. dgallis@syr.edu
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Descriptor/Qualifier:
Humans
Molecular Dynamics Simulation*
Protein Structure, Secondary
Transcobalamins / chemistry*,  metabolism*
Vitamin B 12 / chemistry*,  metabolism*
Chemical
Reg. No./Substance:
0/Transcobalamins; 68-19-9/Vitamin B 12

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine


Previous Document:  A newly designed cell-permeable SNARF derivative as an effective intracellular pH indicator.
Next Document:  Synthesis of 2-acylfurans from 3-(1-alkynyl)-2-alken-1-ones via the oxidation of gold-carbene interm...