Search

Your search keyword '"Juan A. Subirana"' showing total 3 results
Start Over Author "Juan A. Subirana" Publisher wiley-blackwell
3 results on '"Juan A. Subirana"'

1. Structure and supramolecular packing features of the dipeptide Arg-Val acetate

Author

Juan A. Subirana, Rosario Recacha, and Núria Verdaguer

Subjects
Models, Molecular, Arginine, Protein Conformation, Stereochemistry, Hydrochloride, Supramolecular crystals, Supramolecular chemistry, Peptide, Peptide aggregation, Biochemistry, chemistry.chemical_compound, Endocrinology, X-Ray Diffraction, Dipeptide, Valine, Molecule, Methylene, chemistry.chemical_classification, Hydrogen Bonding, Dipeptides, chemistry, X-ray structure
Abstract

The title compound crystallizes in the zwitterionic form. The crystal forms a supramolecular structure with the peptide molecules organized in head-to-tail columns in the b direction. The arginine side-chains and acetate ions interact with neighbor peptides in the c direction. Infinite hydrophobic columns are present in the a direction; they involve the valine side-chains, the acetate methyl groups and the methylene groups of the arginine side- chains. This three-dimensional organization is similar to that found in Lys- Val hydrochloride.

Published
1997

2. Nonsequence-specific arginine interactions in the nucleosome core particle.

Author

Maria García-Pérez, Marta Pinto, and Juan A. Subirana

Subjects
ARGININE, AMINO acids, CHEMICAL structure, DNA, ELECTRIC fields
Abstract

We have analyzed the relative orientation of basic amino acid side chains towards DNA in the nucleosome core particle. The electric field created by DNA phosphates has no apparent preferential orientation: no favored orientation of the arginine guanidinium group is found. Arginine may be either directly hydrogen bonded to a phosphate oxygen or stabilized in the minor groove by van der Waals contacts and the local negative electric field. On the other hand, the phosphate oxygen atoms hydrogen bonded to arginines are always found close to the plane defined by the guanidinium group. Thus it can be concluded that the interactions of arginine are strongly directional, those of phosphate are not. We also find that a highly charged fragment of histone H2B, which is placed between two DNA turns, has a very variable conformation. An increase in protein positive charge density apparently allows multiple nonspecific protein conformations when interacting with DNA. © 2003 Wiley Periodicals, Inc. Biopolymers 69: 432–439, 2003 [ABSTRACT FROM AUTHOR]

Published
2003

Catalog

Books, media, physical & digital resources
See catalog results