N-H from protein

N-H from secondary amide in proteins N-H (2v) stretching from secondary amide in proteins N-H from protein ... 

Polyamide 11 N-H from primary amides N-H from primary amides N-H from protein Polyamide 11... 

Noncovalent interactions play a key role in biodisciplines. A celebrated example is the secondary structure of proteins. The 20 natural amino acids are each characterized by different structures with more or less acidic or basic, hydrophilic or hydrophobic functionalities and thus capable of different intermolecular interactions. Due to the formation of hydrogen bonds between nearby C=0 and N-H groups, protein polypeptide backbones can be twisted into a-helixes, even in the gas phase in the absence of any solvent." A protein function is determined more directly by its three-dimensional structure and dynamics than by its sequence of amino acids. Three-dimensional structures are strongly influenced by weak non-covalent interactions between side functionalities, but the central importance of these weak interactions is by no means limited to structural effects. Life relies on biological specificity, which arises from the fact that individual biomolecules communicate through non-covalent interactions." " Molecular and chiral recognition rely on... 

N-H from CONH2as thermal unfolding of RNase A protein in aqueous solution (assigned to an N-H combination band)... 

N-H (vN-H and 8N-H combination) for NH, (ammonia) in water N-H (3v) for NH5 (ammonia) in water N-H from CONHj as thermal unfolding of RNase A protein in aqueous solution (assigned to an N-H combination band)... 

Another type of ion is formed almost uniquely by the electrospray inlet/ion source which makes this technique so valuable for examining substances such as proteins that have large relative molecular mass. Measurement of m/z ratios usually gives a direct measure of mass for most mass spectrometry because z = 1 and so m/z = m/1 = m. Values of z greater than one are unusual. However, for electrospray, values of z greater than one (often much greater), are quite coimnonplace. For example, instead of the [M + H]+ ions common in simple Cl, ions in electrospray can be [M + n-H]- where n can be anything from 1 to about 30. 

Gaebler, O.H., Vitti, T.G. and Vukmirovich, R. 1966 Isotope effects in metabolism of N and from unlabeled dietary proteins. CanadianJournal of Biochemistry 44 1249-1257. 

For the purification of RHG, which has been described before (6), A. aculeatus was grown in sugar-beet pulp medium for 48 h. From a 2 1 culture containing 3.2 g protein, about 5 mg RHG was obtained after purification. Analysis by SDS-PAGE revealed only one band of about 55 kDa and thus the enzyme appeared to be pure. After N-glycanase treatment and SDS-PAGE analysis, a smaller protein band of about 46 kDa was visible (Fig.l). 

Figure 5.65 provides theoretical evidence that resonance-assisted H-bonding can serve as an effective mechanism for switching a methyl rotor from one preferred conformation to another, or for controlling the stiffness of torsional motions in alkylated amides. In particular, the torsional potentials of proteins (more specifically, the Ramachandran b angle at Ca) should be sensitive to N—H- O and related H-bonding interactions involving the amide backbone. In principle, this electronic... 

A protein s secondary structure arises from the formation of intra- and inter-molecular hydrogen bonds. All carboxyl group oxygens and amine hydrogens of a polypeptide participate in H-bonding. Protein secondary structure also derives from the fact that although all C-N bonds in peptides have some double bond character and cannot rotate, rotation about the Co-N and Ca-C bonds is possible and is... 

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