Proteins salt bridges

This technique also provides a means of identifying each covalently linked, i/irer-protein salt-bridged site through identification of the peptide component contributed by each protein of the linked pairs and/or multimers. This is an aspect of this ongoing project. Such data will provide more specific... 

Two other hydroxyls in NeuSAc form well-defined hydrogen bonds to the protein. The hydroxyl group on C2 interacts with residue AsplSl. Despite being adjacent to arginine residues, AsplSl is not involved in a protein-protein salt-bridge. The hydroxyl group on C4... 

In a recent theoretical study, Shipman (36) proposed several specific models for the herbicide binding site on PS II. It was proposed that the PS II herbicides bind electrostatically at or near a protein salt bridge or the terminus of an alpha helix. 

It is important to notice that the united-atom simplification cannot be applied to functional hydrogens which are involved in the formation of a hydrogen hond or a salt bridge. This would destroy interactions important for the structural integrity of the protein. Removing the hydrogen at the u-carbon of the peptide backbone is also dangerous, because it prevents racemization of the amino acid. 

Also important for stabilizing a protein s tertiary stmcture are the formation of disulfide bridges between cysteine residues, the formation of hydrogen bonds between nearby amino acid residues, and the presence of ionic attractions, called salt bridges, between positively and negatively charged sites on various amino acid side chains within the protein. 

Salt bridge (Section 26.9) The ionic attraction between two oppositely charged groups in a protein chain. 

While loops lack apparent stmcmral regularity, they exist in a specific conformation stabilized through hydrogen bonding, salt bridges, and hydrophobic interactions with other portions of the protein. However, not all portions of proteins are necessarily ordered. Proteins may contain disordered regions, often at the extreme amino or carboxyl terminal, characterized by high conformational flexibility. In many instances, these disor-... 

One way in which to probe the structural surroundings of a protein is to monitor the pH behavior of specific carbon sites of the C probes. pH-titration studies, of given resonances, had previously been used for probing of the protein structure, because they are known to provide information concerning electrostatic (salt-bridging) interactions in the protein, neighboring group-ionizations, and local environments. ... 

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