N-terminal segment

Waals interactions with the PI Cys, and also located basic Arg and Lys residues in position to interact with the P6 acidic residue. More detail of the binding of the N-terminal (i.e., P residues) part of the substrate was subsequently inferred from NMR studies showing a p-sheet interaction between this N-terminal segment of the substrate and enzyme largely confined to within the C-terminal p-barrel (Cicero et al. 1999). 

Gordon, L.M., Lee, K.Y.C., Lipp, M.M., Zasadzinski, J.A., Walther, F.J., Sherman, M. A., and Waring, A.J. Conformational mapping of the N-terminal segment of surfactant protein B in lipid using C-13-enhanced Fourier transform infrared spectroscopy. J. Peptide Res. 

Barhanin et al. (26) chemically modified the side chains of several residues to correlate structure and function in As II. Their results established the importance of charged residues for the function of the toxin. They showed that Arg-13 is essential for binding to the sodium channels as well as for toxicity, while the aspartate, glutamate, and lysine residues in the N-terminal segment of the protein are... 

For type II membrane proteins, in which their N-terminal segment is exposed at the cytosolic side, the signal was found on their N terminus. There are relatively few type II proteins in the ER. This time, a diarginine motif, XXRR, is important. Its variations include XRR, XXXRR, XRXR, and XXRXR. The replacement of R with K may be allowed in some cases. 

Fig. 6. Global structural characterization of mPrP(23-231). Dots represent the 98 residues of the N-terminal segment 23-120, which shows features of a flexible, random coil-like polypeptide with rotational correlation times for the groups of Tc

Signal sequences and translocation. In 1971, Blobel and Sabatini postulated that for some proteins an N-terminal segment of newly synthesized polypeptide chains contains a signal sequence or leader peptide of 15-30 amino acids which carries information concerning the location of the mature protein in the cell.23 280 The rather nonpolar signal sequences of proteins destined for secretion from cells would interact... 

Alam et al. (2001) studied the inhibitory action of CNBR fragments of the RATI on amylase 2 purified from porcine pancreas and reported that the fragment comprising the first 10 amino acids of the N-terminal segment inhibited amylase competitively. NH2-Ser-Val-Gly-Thr-Ser-Cys-Ile-Pro-Gly-OH was most effective. A serine to alanine transformation diminished the inhibitory effect. Blocking the N-terminus abolished the a-amylase inhibitory activity. It may be presumed that the abolition of the a-amylase inhibitory activity with 2,4,6-trinitrobenzenesulfonic acid as observed by Shivraj and Pattabhiraman (1981) may have been due to its interaction with cysteine. Figure 6.9 shows a representation of this ragi protein with its ability to bind both a-amylase and trypsin with its two arms. 

One of the most striking features of the rhodopsin structure is the complexity and compactness of a helix bundle cap or plug formed from the extracellular interhelix loops and N-terminal segment (19). Together, the N-terminal... 

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