Results 221 to 230 of about 53,124 (263)

The helix‐loop‐helix domain: A common motif for bristles, muscles and sex

BioEssays, 1991
AbstractThree apparently unrelated developmental processes – mammalian myogenesis, the choice of neural fate and sex determination in Drosophila – are controlled by a common mechanism. Most of the genes governing these processes encode transcriptional factors that contain the helix‐loop‐helix (HLH) motif.
J, Garrell, S, Campuzano
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Modified Helix‐Loop‐Helix Motifs of Calmodulin

European Journal of Biochemistry, 1997
The four calcium‐binding sites, called the helix‐loop‐helix, or the EF‐hand motifs, of calmodulin differ in their ion‐binding affinities; this has been thought to arise due to the variations in the sequences of the loop regions where the ion binds. We focus attention here on the role of the flanking helical regions on the calcium‐binding affinities ...
Y, Sharma, S, Chandani, M B, Sukhaswami, L, Uma, D, Balasubramanian, T, Fairwell   +5 more
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Physics-based approach to extend a de novo TIM barrel with rationally designed helix-loop-helix motifs

Protein Engineering, Design and Selection, 2023
Abstract Computational protein design promises the ability to build tailor-made proteins de novo. While a range of de novo proteins have been constructed so far, the majority of these designs have idealized topologies that lack larger cavities which are necessary for the incorporation of small molecule binding sites or enzymatic ...
Sina, Kordes, Julian, Beck, Sooruban, Shanmugaratnam, Merle, Flecks, Birte, Höcker   +4 more
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Covalent control of polypeptide folding. Induction of helix-loop-helix motifs by bridging

Journal of the Chemical Society, Perkin Transactions 2, 2000
A de novo designed helix-loop-helix polypeptide motif is induced by introduction of an interhelical carbon bridge by a site selective reaction. The proposed structure of the bridged polypeptide is based on CD spectroscopy and previous structural studies of polypeptides with similar amino acid sequences. The polypeptide used for the bridging experiments
Pernilla Korsgren, Per Ahlberg, Lars Baltzer   +2 more
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Molecular Dynamics Simulations to Determine the Optimal Loop Length in the Helix-loop-helix Motif

Journal of Biomolecular Structure and Dynamics, 2003
In this study, 100 ps molecular dynamics simulations were conducted to determine the optimal length of the Gly loop in the helix-loop-helix motif. The results revealed that the length of the loop significantly affected the stability of the two alpha-helices. In addition, the optimal loop length to maintain the highest helicity of the target peptide was
Hsuan-Liang, Liu, Yann-Chi, Shu, Yann-Huei, Wu   +2 more
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Helix-loop-helix motif in GnRH associated peptide is critical for negative regulation of prolactin secretion

Journal of Molecular Biology, 1997
The GnRH associated prolactin inhibiting factor (GAP) reveals the signature sequence associated with the helix-loop-helix structural motif. A number of different peptide fragments of GAP were designed, synthesized and analysed by circular dichroism and by an in vivo assay for prolactin secretion inhibiting activity.
G B, Chavali, S, Nagpal, S S, Majumdar, O, Singh, D M, Salunke   +4 more
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Structures and metal-ion-binding properties of the Ca2+-binding helix–loop–helix EF-hand motifs

Biochemical Journal, 2007
The ‘EF-hand’ Ca2+-binding motif plays an essential role in eukaryotic cellular signalling, and the proteins containing this motif constitute a large and functionally diverse family. The EF-hand is defined by its helix–loop–helix secondary structure as well as the ligands presented by the loop to bind the Ca2+ ion. The identity of these ligands is semi-
Jessica L, Gifford, Michael P, Walsh, Hans J, Vogel   +2 more
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A simple procedure for assigning a sequence motif with an obscure pattern: application to the basic/helix-loop-helix motif

"Protein Engineering, Design and Selection", 1994
We have developed a simple method to assign a sequence motif with an obscure pattern. Given a multiple sequence alignment for a region of protein that is known or strongly believed to have the same secondary and tertiary structures, the quantification method by principal component analysis is designed to find the regions most likely to have the same ...
K, Horimoto, H, Yamamoto, K, Yanagi, K, Ohshima, J, Otsuka   +4 more
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The relationship between structure and reactivity in RA-42, a designed helix–loop–helix motif

Journal of the Chemical Society, Perkin Transactions 2, 1997
RA-42, a polypeptide with 42 amino acids, has previously been shown to react with p-nitrophenyl fumarate (1) and site selectively form an amide at the side chain of ornithine-15 in aqueous solution and in 10 vol% 2,2,2-trifluoroethanol (TFE).
Ann-Christin Lundh, Klas Broo, Lars Baltzer   +2 more
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Noncovalent Binding of a Reaction Intermediate by a Designed Helix‐Loop‐Helix Motif—Implications for Catalyst Design

ChemBioChem, 2003
AbstractIn our search for a catalyst for the transamination reaction of aspartic acid to form oxaloacetate, twenty‐five forty‐two‐residue sequences were designed to fold into helix‐loop‐helix dimers and form binding sites for the key intermediate along the reaction pathway, the aldimine.
Malin, Allert, Lars, Baltzer
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