02049nas a2200253   4500008004100000022001400041245017300055210006900228260010600297300001400403490000700417520104900424653001601473653001301489653001301502653001201515653002401527100002501551700001701576700002401593700002401617700002801641856012601669       2012                        eng d  a0040-402000aExpanding the structural repertoire of beta/alpha Ant-Pro (anthranilic acid-proline) oligomers into gamma/alpha 2-Amb-Pro (2-aminomethyl benzoic acid-proline) oligomers0 aExpanding the structural repertoire of betaalpha AntPro anthrani  aTHE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLANDbPERGAMON-ELSEVIER SCIENCE LTDcJUN  a4399-44050 v683 a<p>In this article, we report a novel class of heterogeneous synthetic oligomers featuring the conformationally constrained amino acid residues - 2-aminomethyl benzoic acid (2-Amb) and proline (Pro) in repeating sequences. Oligomers as large as hexadecamers featuring the conformationally restricted gamma/alpha 2-Amb-Pro motif have been assembled using solution-phase Boc strategy, following multi-step synthetic sequences starting from the commercially available O-toluic acid. EDC-mediated peptide coupling has been found to be optimum for the assembly of the relatively non-polar oligomers, which could be readily purified by the standard column chromatographic purification procedures. This study offers considerable prospects of expanding the structural repertoire of beta/alpha Ant-Pro motif, which has been described earlier to assume right-handed helical architecture displaying robust nine-membered-ring closed network of hydrogen-bonding interactions, into gamma/alpha 2-Amb-Pro motif. (C) 2012 Elsevier Ltd. All rights reserved.</p>10aAmino acids10aFoldamer10aPeptides10aProline10aSynthetic oligomers1 aRamesh, Veera, V. E.1 aPriya, Gowri1 aRajamohanan, P., R.1 aHofmann, Hans-Joerg1 aSanjayan, Gangadhar, J.  uhttps://library.ncl.res.in/content/expanding-structural-repertoire-betaalpha-ant-pro-anthranilic-acid-proline-oligomers-002655nas a2200325   4500008004100000022001400041245008700055210006900142260007700211300001400288520149300302653001301795653002001808653002001828653002301848100002701871700002401898700003301922700002101955700002201976700002501998700002102023700002602044700002402070700002302094700002602117700003502143700002802178856012302206       2013                        eng d  a1434-193X00aAnt-pro reverse-turn motif. structural features and conformational characteristics0 aAntpro reverseturn motif structural features and conformational   aBOSCHSTRASSE 12, D-69469 WEINHEIM, GERMANYbWILEY-V C H VERLAG GMBHcJUN  a3529-35423 a<p>This article details the characteristic conformational features of the Ant-Pro reverse turn ? a folded pseudo -turn motif that displays a closed nine-membered-ring hydrogen-bonded network involving just two amino acid residues, namely anthranilic acid (Ant; a constrained -amino acid), and proline (Pro; a constrained -amino acid). The results from the extensive investigation of ten crystal structures and their NMR conformations in the solution state provide a clear idea about the conformational characteristics of the Ant-Pro reverse turn. The Ant and Pro residues, which form the turn segment, maintain a perfect antiperiplanar orientation throughout, leaving little possibility for the formation of the otherwise possible six-membered hydrogen-bonding that requires a coplanar disposition of the two amino acid residues, as clearly evident from investigation of several crystal structures. The closed hydrogen-bonded network observed in the Ant-Pro reverse turn motif, formed in the forward direction of the sequence (12 amino acid interactions) involving only two amino acid residues, is in stark contrast to the native -turns that involve four residues to form hydrogen-bonded network featuring backward 14 amino acid interactions. The readily available two-residue Ant-Pro motif raises the possibility of a practical utility, particularly in the application of rigidifying flexible peptide backbones by inserting the robust Ant-Pro reverse turn motifs into their backbone.</p>10aPeptides10aPeptidomimetics10aProtein folding10aProtein structures1 aThorat, Vijaykumar, H.1 aIngole, Tukaram, S.1 aVijayadas, Kuruppanthara, N.1 aNair, Roshna, V.1 aKale, Sangram, S.1 aRamesh, Veera, V. E.1 aDavis, Hilda, C.1 aPrabhakaran, Panchami1 aGonnade, Rajesh, G.1 aGawade, Rupesh, L.1 aPuranik, Vedavati, G.1 aRajamohanan, Pattuparambil, R.1 aSanjayan, Gangadhar, J.  uhttps://library.ncl.res.in/content/ant-pro-reverse-turn-motif-structural-features-and-conformational-characteristics-0