Beta-turns

A distinctive feature of the protease is the presence of a mobile beta turn in each subunit, which serves as a flap covering the active site. For substrate to get access to the active site, the flaps have to move away in what must be an ongoing dynamic... 

Asakura, T., Ashida, J., Yamane, T., Kameda, T., Nakazawa, Y., Ohgo, K., and Komatsu, K. (2001). A repeated beta-turn structure in poly(Ala-Gly) as a model for silk I of Bombyx mod silk fibroin studied with two-dimensional spin-diffusion NMR under off magic angle spinning and rotational echo double resonance. / Mol. Biol. 306, 291-305. 

Lazo, N. D., and Downing, D. T. (1999). Crystalline regions of Bombyx mori silk fibroin may exhibit beta-turn and beta-helix conformations. Macromolecules 32, 4700-4705. Lee, K. H. (2004). Silk sericin retards the crystallization of silk fibroin. Macromol. Rapid Commun. 25, 1792-1796. 

Peptide E n.a. 25 SDS Two beta-turns, intermediate order parameters 102... 

Erard M, Lakhdar-Ghazal F, Amalric F (1990) Repeat peptide motifs which contain beta-turns and modulate DNA condensation in chromatin. Eur J Biochem 191 19—26 Erard MS, Belenguer P, Caizergues-Ferrer M, Pantaloni A, Amalric F (1988) A major nucleolar protein, nucleolin, induces chromatin decondensation by binding to histone HI. Eur J Biochem 175 525—530 Falaschi A (2000) Eukaryotic DNA replication a model for a fixed double replisome. Trends Genet 16 88-92... 

Garland SL, Dean PM. (1999) Design criteria for molecular mimics of fragments of the beta-turn. 1. C alpha atom analysis. /. Comput.-Aided Mol. Des. 13 469-483. 

Keywords Cyclopeptides Depsipeptides Peptoids Macrocycles Diketopiper-azines Benzodiazepines Ugi-reaction Polycyclic compounds Orthogonal reactivity Sequential reactions Iteration Bifunctional building blocks Medium sized rings Beta-turn motif... 

The type III j8 turn is similar to a type I turn but has the ( ), angles of a 310 helix and the two chains emerging from the turn are not as nearly parallel as they are in type I turns. Beta turns of the less common types Y, IT, and III have a left-handed twist. As can be seen in Fig. 2-24, this permits a better match to the twist of strands in a P sheet. Unless glycine is present, these bends are less stable because of steric hindrance.214 215 Polar side chain groups such as those of aspartate or asparagine often form hydrogen bonds to the central peptide units of P turns.214... 

Figure 30-3 Possible secondary structure of somatostatin with a beta turn at residues 7-10 and a disulfide bond between positions 3 and 14.

Ma, K., and Wang, K. (2003). Malleable conformation of the elastic PEVK segment of titin Non-cooperative interconversion of polyproline II helix, beta-turn and unordered structures. Biochem.J. 374, 687-695. 

For polypeptide, the B program provides options for building various protein conformations including 3-10 helix, alpha helix, alpha helix (L-H), beta sheet (anti-prl), beta sheet (parallel), various beta turns, extended, gamma turns, omega helix, pi helix, polyglycine, and polyproline. Choose the desired conformation and isomer (l or d) and then add amino acids from N-terminus to construct polypeptide chain. 

Manning, M.C., Illangasekare, M., and Woody, R.W. "Circular-dichroism studies of distorted alpha-helices, twisted beta-sheets, and beta-turns". Biophys. Chem. 31(1-2), 77-86 (1988). 

Wentzel, A., Christmann, A., Kratzner, R., and Kolmar, H. (1999). Sequence requirements of the GPNG beta-turn of the Echallium elaterium, trypsin inhibitor II explored by combintorial library screening. / Biol. Chem. 274, 21037-21043. 

LPL is a glycoprotein (8% by weight carbohydrate) with a native molecular weight of around 100 000 Da and a monomer subunit of about 50 000 Da (Kinnunen et al., 1976). Senda et al. (1987) calculated the molecular weight of the unglycosylated form as 50 548 Da based on the cDNA encoding it. LPL has a serine at the active site, located in a beta turn in the enzyme, similar to that at the active site of other serine hydrolases (Reddy et al., 1986). 

G. Kotovych, The importance of the N-terminal beta-turn in bradykinin antagonists,/. Biomd. Struct. Dyn. 2000, 18, 249-260. 

J. H. Baik, S. K. Lim, Type I beta-turn conformation is important for biological activity of the melanocyte-stimulating hormone analogues, Eur. J. Biochem. 

T. R. Webb, Application of a novel design paradigm to generate general nonpeptide combinatorial scaffolds mimicking beta turns synthesis of ligands for somatostatin receptors, Bioorg. and Med. Chem. 2003, 11, 5059-5068. 

I. Im, T. R. Webb, Y. D. Gong, J.-I. Kim, J.-C. Kim, Solid phase synthesis of tetrahydro-l,4-benzodiazepine-2-one derivatives as a beta-turn peptidomimic library,/. Comb. Chem. 2004, 6, 207-213. 

G. Muller, G. Hessler, H. Y. Decornez, Are beta-turn mimetics mimics of beta-turns Angew. Chem., Int. Ed. 2000, 39, 894-896. 

G. Mer, E. Kellenberger, j. F. Lefevre, Alpha-helix mimicry of a beta-turn,... 

Recent applications of Kohonen self-organizing maps include construction of phylogenetic trees from sequence information (Wang et al., 1998) predicting cleavage sites in protein (Cai et al., 1998a) prediction of beta-turns (Cai et al., 1998b) ... 

Amino Acids Have Different Propensities for Forming Alpha Helices, Beta Sheets, and Beta Turns... 

Yeagle, P. L., Alderfer, J. L., Salloum, A. C., Ali, L., Albert, A. D. The first and second cytoplasmic loops of the G protein receptor, rhodopsin, independently form beta-turns. Biochemistry, 1997, 36, 3864-3869. 

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