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Journal articles on the topic 'Hybrid Peptide Helices'

Author: Grafiati
Published: 6 September 2023

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1

Misra, Rajkumar, Gijo George, Rahi M. Reja, Sanjit Dey, Srinivasarao Raghothama, and Hosahudya N. Gopi. "Structural insight into hybrid peptide ε-helices." Chemical Communications 56, no. 14 (2020): 2171–73. http://dx.doi.org/10.1039/c9cc07413a.

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2

Ananda, Kuppanna, Prema G. Vasudev, Anindita Sengupta, K. Muruga Poopathi Raja, Narayanaswamy Shamala, and Padmanabhan Balaram. "Polypeptide Helices in Hybrid Peptide Sequences." Journal of the American Chemical Society 127, no. 47 (November 2005): 16668–74. http://dx.doi.org/10.1021/ja055799z.

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3

Sastry, Mallika, Christopher Brown, Gerhard Wagner, and Thomas D. Clark. "Cyclic Peptide Helices: A Hybrid β-Hairpin/β-Helical Supersecondary Structure." Journal of the American Chemical Society 128, no. 33 (August 2006): 10650–51. http://dx.doi.org/10.1021/ja062737f.

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4

Chatterjee, Sunanda, Rituparna Sinha Roy, and P. Balaram. "Expanding the polypeptide backbone: hydrogen-bonded conformations in hybrid polypeptides containing the higher homologues of α-amino acids." Journal of The Royal Society Interface 4, no. 15 (January 23, 2007): 587–606. http://dx.doi.org/10.1098/rsif.2006.0203.

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Half a century has passed since the hydrogen-bonded secondary structures of polypeptides and proteins were first recognized. An extraordinary wealth of conformational information is now available on peptides and proteins, which are formed of α-amino acid residues. More recently, the discovery of well-folded structures in oligopeptides containing β-amino acids has focused a great deal of current interest on the conformational properties of peptides constructed from higher homologues (ω) of α-amino acids. This review examines the nature of intramolecularly hydrogen-bonded conformations of hybrid peptides formed by amino acid residues, with a varying number of backbone atoms. The β-turn, a ubiquitous structural feature formed by two residue (αα) segments in proteins and peptides, is stabilized by a 10-atom (C 10 ) intramolecular 4→1 hydrogen bond. Hybrid turns may be classified by comparison with their αα counterparts. The available crystallographic information on hydrogen-bonded hybrid turns is surveyed in this review. Several recent examples demonstrate that individual ω-amino acid residues and hybrid dipeptide segments may be incorporated into the regular structures of α-peptides. Examples of both peptide helices and hairpins are presented. The present review explores the relationships between folded conformations in hybrid sequences and their counterparts in all α-residue sequences. The use of stereochemically constrained ω-residues promises to expand the range of peptide design strategies to include ω-amino acids. This approach is exemplified by well-folded structures like the C 12 (αγ) and C 14 (γγ) helices formed in short peptides containing multiply substituted γ-residues. The achiral γ-residue gabapentin is a readily accessible building block in the design of peptides containing γ-amino acids. The construction of globular polypeptide structures using diverse hybrid sequences appears to be a realistic possibility.
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Bandyopadhyay, Anupam, and Hosahudya N. Gopi. "Hybrid Peptides: Direct Transformation of α/α, β-Unsaturated γ-Hybrid Peptides to α/γ-Hybrid Peptide 12-Helices." Organic Letters 14, no. 11 (May 18, 2012): 2770–73. http://dx.doi.org/10.1021/ol300987d.

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6

Schramm, Peter, Gangavaram V. M. Sharma, and Hans-Jörg Hofmann. "Helix formation in β/δ-hybrid peptides: Correspondence between helices of different peptide foldamer classes." Biopolymers 94, no. 3 (October 14, 2009): 279–91. http://dx.doi.org/10.1002/bip.21325.

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7

Pullen, J. K., M. D. Tallquist, R. W. Melvold, and L. R. Pease. "Recognition of a single amino acid change on the surface of a major transplantation antigen is in the context of self peptide." Journal of Immunology 152, no. 7 (April 1, 1994): 3445–52. http://dx.doi.org/10.4049/jimmunol.152.7.3445.

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Abstract The transcripts encoding two strongly alloantigenic class I mutant molecules, Kdm4 and Kdm5, were characterized and found to encode products that differ from the parental Kd glycoprotein by single amino acid substitutions. The Kdm4 molecule has an amino acid change at position 114, an integral component of a beta-sheet associated with pockets D and E of the peptide binding site. The basis for strong alloantigenicity of the variant molecule can be attributed to differences in peptide binding that were visualized by HPLC analysis of eluted peptides. In contrast, the Kdm5 molecule differs from the parent at position 158, a component of the alpha-helix that is not associated with any of the pockets of the peptide binding site. No differences in peptide binding by Kdm5 in comparison with the parent Kd molecule were seen by HPLC, suggesting that the variant and parent molecules bind the same set of peptides. The ability of (dm4 x dm5) F1 hybrid mice to recognize and lyse BALB/c stimulator cells indicates that the alloantigenic properties determined by the 158 substitution result from the interactions of the alpha-helix regions (changed in dm5) with the pockets of the binding site (changed in dm4). We conclude that self peptides shared by the F1 hybrid and the BALB/c stimulator cells are recognized in the context of structural features of the helices of the Ag-presenting molecule as alloantigenic determinants.
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8

Bandyopadhyay, Anupam, Sandip V. Jadhav, and Hosahudya N. Gopi. "α/γ4-Hybrid peptide helices: synthesis, crystal conformations and analogy with the α-helix." Chemical Communications 48, no. 57 (2012): 7170. http://dx.doi.org/10.1039/c2cc32911e.

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9

Smirnova, Evgeniya V., Tatiana V. Rakitina, George A. Saratov, Anna A. Kudriaeva, and Alexey A. Belogurov. "Deconvolution of the MBP-Bri2 Interaction by a Yeast Two Hybrid System and Synergy of the AlphaFold2 and High Ambiguity Driven Protein-Protein Docking." Crystals 12, no. 2 (January 28, 2022): 197. http://dx.doi.org/10.3390/cryst12020197.

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Myelin basic protein (MBP) is one of the key proteins in the development of multiple sclerosis (MS). However, very few intracellular MBP partners have been identified up to now. In order to find proteins interacting with MBP in the brain, an expression library from the human brain was screened using a yeast two-hybrid system. Here we showed that MBP interacts with the C-terminal 24-residue peptide of Integral transmembrane protein II associated with familial British and Danish dementia (ITM2B/Bri2 or Bri2). This peptide (Bri23R) was one residue longer than the known Bri23 peptide, which is cleaved from the C-terminus of Bri2 during its maturation in the Golgi and has physiological activity as a modulator of amyloid precursor protein processing. Since the spatial structures for both MBP and Bri2 were not known, we used computational methods of structural biology including an artificial intelligence system AlphaFold2 and high ambiguity driven protein-protein docking (HADDOCK 2.1) to gain a mechanistic explanation of the found protein-protein interaction and elucidate a possible structure of the complex of MBP with Bri23R peptide. As expected, MBP was mostly unstructured, although it has well-defined α-helical regions, while Bri23R forms a stable β-hairpin. Simulation of the interaction between MBP and Bri23R in two different environments, as parts of the two-hybrid system fusion proteins and in the form of single polypeptides, showed that MBP twists around Bri23R. The observed interaction results in the adjustment of the size of the internal space between MBP α-helices to the size of the β-hairpin of Bri23R. Since Bri23 is known to inhibit aggregation of amyloid oligomers, and the association of MBP to the inner leaflet of the membrane bilayer shares features with amyloid fibril formation, Bri23 may serve as a peptide chaperon for MBP, thus participating in myelin membrane assembly.
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10

Misra, Rajkumar, Abhijith Saseendran, Gijo George, Kuruva Veeresh, K. Muruga Poopathi Raja, Srinivasarao Raghothama, Hans-Jörg Hofmann, and Hosahudya N. Gopi. "Structural Dimorphism of Achiral α,γ-Hybrid Peptide Foldamers: Coexistence of 12- and 15/17-Helices." Chemistry - A European Journal 23, no. 15 (February 14, 2017): 3764–72. http://dx.doi.org/10.1002/chem.201605753.

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11

Jadhav, Sandip V., Anupam Bandyopadhyay, and Hosahudya N. Gopi. "Protein secondary structure mimetics: crystal conformations of α/γ4-hybrid peptide12-helices with proteinogenic side chains and their analogy with α- and β-peptide helices." Org. Biomol. Chem. 11, no. 3 (2013): 509–14. http://dx.doi.org/10.1039/c2ob26805a.

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12

Ganesh Kumar, Mothukuri, Varsha J. Thombare, Mona M. Katariya, Kuruva Veeresh, K. Muruga Poopathi Raja, and Hosahudya N. Gopi. "Non-classical Helices withcisCarbon-Carbon Double Bonds in the Backbone: Structural Features of α,γ-Hybrid Peptide Foldamers." Angewandte Chemie International Edition 55, no. 27 (June 6, 2016): 7847–51. http://dx.doi.org/10.1002/anie.201602861.

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13

Ganesh Kumar, Mothukuri, Varsha J. Thombare, Mona M. Katariya, Kuruva Veeresh, K. Muruga Poopathi Raja, and Hosahudya N. Gopi. "Non-classical Helices withcisCarbon-Carbon Double Bonds in the Backbone: Structural Features of α,γ-Hybrid Peptide Foldamers." Angewandte Chemie 128, no. 27 (June 6, 2016): 7978–82. http://dx.doi.org/10.1002/ange.201602861.

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14

Jadhav, Sandip V., Rajkumar Misra, and Hosahudya N. Gopi. "Foldamers to Nanotubes: Influence of Amino Acid Side Chains in the Hierarchical Assembly of α,γ4-Hybrid Peptide Helices." Chemistry - A European Journal 20, no. 50 (October 24, 2014): 16523–28. http://dx.doi.org/10.1002/chem.201404961.

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15

Jagadeesh, Bharatam, Anabathula Prabhakar, Ganti Dattatreya Sarma, Srivari Chandrasekhar, Gudise Chandrashekar, Marepally Srinivasa Reddy, and Bulusu Jagannadh. "Formation of left-handed helices in hybrid peptide oligomers with cis β-sugar amino acid and l-Ala as building blocks." Chem. Commun., no. 4 (2007): 371–73. http://dx.doi.org/10.1039/b612058j.

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16

Beckers, W., L. Villa, S. Gonfloni, L. Castagnoli, S. M. Newton, G. Cesareni, and P. Ghiara. "Increasing the immunogenicity of protein antigens through the genetic insertion of VQGEESNDK sequence of human IL-1 beta into their sequence." Journal of Immunology 151, no. 4 (August 15, 1993): 1757–64. http://dx.doi.org/10.4049/jimmunol.151.4.1757.

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Abstract The immunogenicity of two recombinant protein Ag containing the immunostimulatory sequence of human IL-1 beta 163-171 (VQGEESNDK) genetically engineered into their structure has been evaluated. The IL-1 beta sequence was inserted into the loop between alpha helices D and E of recombinant human ferritin H chain and into the hypervariable region of recombinant flagellin from Salmonella muenchen. The chimeric proteins were injected into mice and the level of humoral immune response developed against the native proteins was assessed by measuring the number of Ag-specific plaque forming cells/spleen or as the level of serum IgG response. The response was compared to that of mice receiving injections with wild-type protein Ag not containing the VQGEESNDK sequence or with hybrid constructs containing unrelated foreign peptide sequences of the same length. A significantly higher immune response was observed in mice immunized with chimeric constructs containing the human IL-1 beta 163-171 sequence. These data suggest that the insertion of the VQGEESNDK sequence may prove useful to increase the immune response against poorly immunogenic recombinant proteins.
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17

Guzzo-Pernell, Nancy, and Geoffrey W. Tregear. "Triple helical DNA formation by a hydrophobic oligonucleotide-peptide hybrid molecule." Australian Journal of Chemistry 53, no. 8 (2000): 699. http://dx.doi.org/10.1071/ch00114.

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Stable triple helical DNA formation with triplex forming oligonucleotide–peptide hybrids, containing hydrophobic peptides, has previously been difficult to achieve. We report hereon stable triplexation with an oligonucleotide–peptide hybrid containing a hydrophobic peptide. The peptide of interest is the gp41b peptide, which is derived from the hydrophobic terminal domain of the HIV transmembrane glycoprotein gp41. Triplex forming oligonucleotides conjugated to the gp41b peptide were prepared with and without intramolecular spacer linkers. Hybrids with appropriate spacers formed stable triplexes whereas those without the linkers did not. Oligonucleotide–peptide conjugates have several applications mainly in control of gene expression, with the peptide enhancing intracellular delivery of the oligonucleotide. The gp41b peptide is one of a number of candidate peptides considered to be potential delivery vectors. Hence, the data presented here may prove to be useful in designing such conjugates. Our data also extend the list of DNA structures known to stabilize triplexes and suggest that triplexation by oligonucleotide–peptide hybrids may be peptide sequence dependent.
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18

Messaoudi, Ilhem, Joël LeMaoult, and Janko Nikolić-Z̆ugić. "The Mode of Ligand Recognition by Two Peptide:MHC Class I-Specific Monoclonal Antibodies." Journal of Immunology 163, no. 6 (September 15, 1999): 3286–94. http://dx.doi.org/10.4049/jimmunol.163.6.3286.

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Abstract The Ig superfamily members TCR and B cell receptor (BCR) share high structural and amino acid homology, yet interact with Ags in a distinct manner. The overall shape of the TCR ligand is rather constant, with the variation coming from the MHC polymorphism and the peptide heterogeneity. Consequently, the TCR α- and β-chains form a relatively flat ligand-binding site that interacts with the peptide:MHC (pep:MHC) ligand in a fixed diagonal orientation relative to the MHC α-helices, with the α- and β-chains of the TCR contacting the N and C termini of the pep:MHC complex, respectively. By contrast, the shape of BCR ligands varies dramatically, and the BCR exhibits much greater variability of the Ag-binding site. The mAbs 25-D1.16 (D1) and 22-C5.9 (C5), specific for the OVA-8:H-2Kb complex, allowed us to directly compare how TCR and BCR approach the same ligand. To that effect, we mapped D1 and C5 footprints over the OVA-8:H-2Kb complex. Using peptide variants and mutant MHC molecules, we show that the D1 and C5 contacts with the OVA-8:Kb complex C terminus overlap with the TCR β-chain footprint, but that this footprint also extends to the regions of the molecule not contacted by the TCR. These studies suggest that D1 and C5 exhibit a hybrid mode of pep:MHC recognition, in part similar to that of the TCR β-chain and in part similar to the conventional anti-MHC Ab.
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19

Jadhav, Sandip V., Rajkumar Misra, Sumeet K. Singh, and Hosahudya N. Gopi. "Efficient Access to Enantiopure γ4-Amino Acids with Proteinogenic Side-Chains and Structural Investigation of γ4-Asn and γ4-Ser in Hybrid Peptide Helices." Chemistry - A European Journal 19, no. 48 (October 21, 2013): 16256–62. http://dx.doi.org/10.1002/chem.201302732.

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20

Bolger, Graeme B., George S. Baillie, Xiang Li, Martin J. Lynch, Pawel Herzyk, Ahmed Mohamed, Lisa High Mitchell, et al. "Scanning peptide array analyses identify overlapping binding sites for the signalling scaffold proteins, β-arrestin and RACK1, in cAMP-specific phosphodiesterase PDE4D5." Biochemical Journal 398, no. 1 (July 27, 2006): 23–36. http://dx.doi.org/10.1042/bj20060423.

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The cAMP-specific phosphodiesterase PDE4D5 can interact with the signalling scaffold proteins RACK (receptors for activated C-kinase) 1 and β-arrestin. Two-hybrid and co-immunoprecipitation analyses showed that RACK1 and β-arrestin interact with PDE4D5 in a mutually exclusive manner. Overlay studies with PDE4D5 scanning peptide array libraries showed that RACK1 and β-arrestin interact at overlapping sites within the unique N-terminal region of PDE4D5 and at distinct sites within the conserved PDE4 catalytic domain. Screening scanning alanine substitution peptide arrays, coupled with mutagenesis and truncation studies, allowed definition of RACK1 and β-arrestin interaction sites. Modelled on the PDE4D catalytic domain, these form distinct well-defined surface-exposed patches on helices-15–16, for RACK1, and helix-17 for β-arrestin. siRNA (small interfering RNA)-mediated knockdown of RACK1 in HEK-293 (human embryonic kidney) B2 cells increased β-arrestin-scaffolded PDE4D5 approx. 5-fold, increased PDE4D5 recruited to the β2AR (β2-adrenergic receptor) upon isoproterenol challenge approx. 4-fold and severely attenuated (approx. 4–5 fold) both isoproterenol-stimulated PKA (protein kinase A) phosphorylation of the β2AR and activation of ERK (extracellular-signal-regulated kinase). The ability of a catalytically inactive form of PDE4D5 to exert a dominant negative effect in amplifying isoproterenol-stimulated ERK activation was ablated by a mutation that blocked the interaction of PDE4D5 with β-arrestin. In the present study, we show that the signalling scaffold proteins RACK1 and β-arrestin compete to sequester distinct ‘pools’ of PDE4D5. In this fashion, alterations in the level of RACK1 expression may act to modulate signal transduction mediated by the β2AR.
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21

Sheppard, Hilary M., Janet C. Harries, Sagair Hussain, Charlotte Bevan, and David M. Heery. "Analysis of the Steroid Receptor Coactivator 1 (SRC1)-CREB Binding Protein Interaction Interface and Its Importance for the Function of SRC1." Molecular and Cellular Biology 21, no. 1 (January 1, 2001): 39–50. http://dx.doi.org/10.1128/mcb.21.1.39-50.2001.

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ABSTRACT The transcriptional activity of nuclear receptors is mediated by coactivator proteins, including steroid receptor coactivator 1 (SRC1) and its homologues and the general coactivators CREB binding protein (CBP) and p300. SRC1 contains an activation domain (AD1) which functions via recruitment of CBP and and p300. In this study, we have used yeast two-hybrid and in vitro interaction-peptide inhibition experiments to map the AD1 domain of SRC1 to a 35-residue sequence potentially containing two α-helices. We also define a 72-amino-acid sequence in CBP necessary for SRC1 binding, designated the SRC1 interaction domain (SID). We show that in contrast to SRC1, direct binding of CBP to the estrogen receptor is weak, suggesting that SRC1 functions primarily as an adaptor to recruit CBP and p300. In support of this, we show that the ability of SRC1 to enhance ligand-dependent nuclear receptor activity in transiently transfected cells is dependent upon the integrity of the AD1 region. In contrast, the putative histone acetyltransferase domain, the Per-Arnt-Sim basic helix-loop-helix domain, the glutamine-rich domain, and AD2 can each be removed without loss of ligand-induced activity. Remarkably, a construct corresponding to residues 631 to 970, which contains only the LXXLL motifs and the AD1 region of SRC1, retained strong coactivator activity in our assays.
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22

Falord, Mélanie, Gouzel Karimova, Aurélia Hiron, and Tarek Msadek. "GraXSR Proteins Interact with the VraFG ABC Transporter To Form a Five-Component System Required for Cationic Antimicrobial Peptide Sensing and Resistance in Staphylococcus aureus." Antimicrobial Agents and Chemotherapy 56, no. 2 (November 28, 2011): 1047–58. http://dx.doi.org/10.1128/aac.05054-11.

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ABSTRACTThe GraSR two-component system (TCS) controls cationic antimicrobial peptide (CAMP) resistance inStaphylococcus aureusthrough the synthesis of enzymes that increase bacterial cell surface positive charges, byd-alanylation of teichoic acids and lysylination of phosphatidylglycerol, leading to electrostatic repulsion of CAMPs. The GraS histidine kinase belongs to the “intramembrane-sensing kinases” subfamily, with a structure featuring a short amino-terminal sensing domain, and two transmembrane helices separated only by a short loop, thought to be buried in the cytoplasmic membrane. The GraSR TCS is in fact a multicomponent system, requiring at least one accessory protein, GraX, in order to function, which, as we show here, acts by signaling through the GraS kinase. ThegraXRSgenes are located immediately upstream from genes encoding an ABC transporter,vraFG, whose expression is controlled by GraSR. We demonstrated that the VraFG transporter does not act as a detoxification module, as it cannot confer resistance when produced on its own, but instead plays an essential role by sensing the presence of CAMPs and signaling through GraS to activate GraR-dependent transcription. A bacterial two-hybrid approach, designed to identify interactions between the GraXSR and VraFG proteins, was carried out in order to understand how they act in detecting and signaling the presence of CAMPs. We identified many interactions between these protein pairs, notably between the GraS kinase and both GraX and the VraG permease, indicating the existence of an original five-component system involved in CAMP sensing and signal transduction to promoteS. aureusresistance.
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23

Dengler, Sebastian, Pradeep K. Mandal, Lars Allmendinger, Céline Douat, and Ivan Huc. "Conformational interplay in hybrid peptide–helical aromatic foldamer macrocycles." Chemical Science 12, no. 33 (2021): 11004–12. http://dx.doi.org/10.1039/d1sc03640h.

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When peptides and helical aromatic foldamers are combined in a macrocycle, an interplay of their properties is observed, including helix handedness bias, helix stabilisation, peptide stretching and peptide resistance to proteolytic degradation.
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24

Londoño, J. A., H. Gras-Masse, C. Dubeaux, A. Tartar, and P. Druilhe. "Secondary structure and immunogenicity of hybrid synthetic peptides derived from two Plasmodium falciparum pre-erythrocytic antigens." Journal of Immunology 145, no. 5 (September 1, 1990): 1557–63. http://dx.doi.org/10.4049/jimmunol.145.5.1557.

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Abstract Multicomponent synthetic vaccines containing both B and T cell epitopes belonging to two different pre-erythrocytic Ag of Plasmodium falciparum are presented. In a di-component hybrid, a circumsporozoite T cell epitope and a peptide representing a liver stage-specific Ag were connected to obtain a reciprocal reinforcement of helical potentials. In a tri-component hybrid, a sequence corresponding to the circumsporozoite repeat tetrapeptide (NPNA) was tandemly synthesized on the N-terminal end of the di-component hybrid. Both hybrid molecules were able to adopt a partial helical conformation in water as determined by circular dichroism studies. To analyze if the different components were immunologically functional in these vaccines, mich bearing genetic backgrounds known to respond or not to the individual components were immunized with the hybrids. The tri-hybrid peptide showed high immunogenic capacity as it elicited, in both H-2b and H-2k mice, high antibody responses against every separate individual sequence. Moreover, the antibodies induced by these conformationally restricted peptides were able to recognize the corresponding native proteins in the liver schizont and the sporozoite surface. H-2d mice, in which the immune response to the individual components was genetically restricted, did respond against the di-hybrid peptide. The tri-hybrid peptide, in which NPNA repeats were present, lacked this H-2d-priming capacity but it triggered antibody production in H-2d mice previously primed with the di-hybrid peptide. These results indicate that multivalent vaccines can provide positive (potentiating) effects by carefully combining structurally well defined epitopes; however, negative (suppressive) effects are also possible suggesting that selection of multivalent vaccine components will require testing of combined molecules to optimize specific immune responses and avoid undesirable effects which may result from negative molecular interactions.
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25

Friedrich, Cornelius G., Armin Quentmeier, Frank Bardischewsky, Dagmar Rother, Regine Kraft, Susanne Kostka, and Heino Prinz. "Novel Genes Coding for Lithotrophic Sulfur Oxidation of Paracoccus pantotrophus GB17." Journal of Bacteriology 182, no. 17 (September 1, 2000): 4677–87. http://dx.doi.org/10.1128/jb.182.17.4677-4687.2000.

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ABSTRACT The gene region coding for lithotrophic sulfur oxidation ofParacoccus pantotrophus GB17 is located on a 13-kb insert of plasmid pEG12. Upstream of the previously described six open reading frames (ORFs) soxABCDEF with a partial sequence ofsoxA and soxF (C. Wodara, F. Bardischewsky, and C. G. Friedrich, J. Bacteriol. 179:5014–5023, 1997), 4,350 bp were sequenced. The sequence completed soxA, and uncovered six new ORFs upstream of soxA, designated ORF1, ORF2, and ORF3, and soxXYZ. ORF1 could encode a 275-amino-acid polypeptide of 29,332 Da with a 61 to 63% similarity to LysR transcriptional regulators. ORF2 could encode a 245-amino-acid polypeptide of 26,022 Da with the potential to form six transmembrane helices and with a 48 to 51% similarity to proteins involved in redox transport in cytochrome c biogenesis. ORF3 could encode a periplasmic polypeptide of 186 amino acids of 20,638 Da with a similarity to thioredoxin-like proteins and with a putative signal peptide of 21 amino acids. Purified SoxXA, SoxYZ, and SoxB are essential for thiosulfate or sulfite-dependent cytochrome creduction in vitro. N-terminal and internal amino acid sequences identified SoxX, SoxY, SoxZ, and SoxA to be coded by the respective genes. The molecular masses of the mature proteins determined by electrospray ionization spectroscopy (SoxX, 14,834 Da; SoxY, 11,094 Da; SoxZ, 11,717 Da; and SoxA, 30,452 Da) were identical or close to those deduced from the nucleotide sequence with differences for the covalent heme moieties. SoxXA represents a novel type of periplasmicc-type cytochromes, with SoxX as a monoheme and SoxA as a hybrid diheme cytochrome c. SoxYZ is an as-yet-unprecedented soluble protein. SoxY has a putative signal peptide with a twin arginine motif and possibly cotransports SoxZ to the periplasm. SoxYZ neither contains a metal nor a complex redox center, as proposed for proteins likely to be transported via the Tat system.
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26

Parry, Christian, Guelaguetza Vazquez-meves, Andrey Ivanov, Xionghao Lin, Namita Kumari, and Sergei Nekhai. "Structure of human ferroportin (SLC40A1) inferred from mass spectrometry restraints." Journal of Immunology 202, no. 1_Supplement (May 1, 2019): 187.35. http://dx.doi.org/10.4049/jimmunol.202.supp.187.35.

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Abstract Nearly all organisms require iron for red blood cell manufacture, respiration, metabolism and immunity, and as cofactor in several enzymes. Paradoxically, free iron is toxic from the production of reactive oxygen species which induce cellular injury and damage to DNA. It is essential that iron is tightly regulated. Ferroportin is the only known exporter of cellular iron in mammals. Its function and expression are tightly regulated by hepcidin. Carriers of ferroportin mutation Q248H show reduced sensitivity to hepcidin, have elevated iron stores and high HIV-1 viral load. In HIV-1 infection, there is marked alteration in iron balance indicated by high ferritin levels. As well, iron-regulating peptide hepcidin is greatly elevated. High iron stores correlate with high morbidity, increased opportunistic infections and faster progression to AIDS: high iron content in bone marrow macrophage parallels greater infection, immune dysfunction and poor prognosis. By contrast, other studies show that patients who were being treated for iron overload with iron chelators had delayed AIDS progression and longer survival. In spite of its importance little structural information is available on human ferroportin, and how iron is transported through ferroportin is not understood. We have built the structure of ferroportin using hybrid methods with restraints from mass spectrometry. Our model comprises 12 transmembrane helices. The iron binding site matches what is seen in crystal structures of distant orthologs. We are using this structure along with functional data to answer outstanding questions about the mechanism of ferroportin, iron transport and the importance of the Q248H mutation found in African and black American populations.
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27

Lane, Andrew N., and Terence C. Jenkins. "Thermodynamics of nucleic acids and their interactions with ligands." Quarterly Reviews of Biophysics 33, no. 3 (August 2000): 255–306. http://dx.doi.org/10.1017/s0033583500003632.

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1. Introduction 2551.1 General thermodynamics 2562. Nucleic acid thermodynamics 2602.1 DNA duplexes 2612.2 RNA duplexes 2632.3 Hybrid DNA–RNA duplexes 2642.4 Hydration 2672.5 Conformational flexibility 2692.6 Thermodynamics 2723. Nucleic acid–ligand interactions 2773.1 Minor groove binders 2783.2 DNA intercalators 2843.3 Triple-helical systems 2883.3.1 Structures 2883.3.2 Hydration 2913.3.3 Thermodynamics 2914. Conclusions 2955. Acknowledgements 2986. References 298In recent years the availability of large quantities of pure synthetic DNA and RNA has revolutionised the study of nucleic acids, such that it is now possible to study their conformations, dynamics and large-scale properties, and their interactions with small ligands, proteins and other nucleic acids in unprecedented detail. This has led to the (re)discovery of higher order structures such as triple helices and quartets, and also the catalytic activity of RNA contingent on three-dimensional folding, and the extraordinary specificity possible with DNA and RNA aptamers.Nucleic acids are quite different from proteins, even though they are both linear polymers formed from a small number of monomeric units. The major difference reflects the nature of the linkage between the monomers. The 5′–3′ phosphodiester linkage in nucleic acids carries a permanent negative charge, and affords a relatively large number of degrees of freedom, whereas the essentially rigid planar peptide linkage in proteins is neutral and provides only two degrees of torsional freedom per backbone residue. These two properties conspire to make nucleic acids relatively flexible and less likely to form extensive folded structures. Even when true 3D folded structures are formed from nucleic acids, the topology remains simple, with the anionic phosphates forming the surface of the molecule. Nevertheless, nucleic acids do occur in a variety of structures that includes single strands and high-order duplex, triplex or tetraplex (‘quadruplex’) forms. The principles of biological recognition and the related problem of understanding the forces that stabilise such folded structures are in some respects more straightforward than for proteins, making them attractive model systems for understanding general biophysical problems. This view is aided by the relatively facile chemical synthesis of pure nucleic acids of any desired size and defined sequence, and the ease of incorporation of a wide spectrum of chemically modified bases, sugars and backbone linkers. Such modifications are considerably more difficult to achieve with oligopeptides or proteins.
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Kilgore, Nicole R., Karl Salzwedel, Mary Reddick, Graham P. Allaway, and Carl T. Wild. "Direct Evidence that C-Peptide Inhibitors of Human Immunodeficiency Virus Type 1 Entry Bind to the gp41 N-Helical Domain in Receptor-Activated Viral Envelope." Journal of Virology 77, no. 13 (July 1, 2003): 7669–72. http://dx.doi.org/10.1128/jvi.77.13.7669-7672.2003.

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ABSTRACT While it has been established that peptides modeling the C-helical region of human immunodeficiency virus type 1 gp41 are potent in vivo inhibitors of virus replication, their mechanism of action has yet to be determined. It has been proposed, but never directly demonstrated, that these peptides block virus entry by interacting with gp41 to disrupt the formation or function of a six-helix bundle structure. Using a six-helix bundle-specific monoclonal antibody with isolate-restricted Env reactivity, we provide the first direct evidence that, in receptor-activated viral Env, C-peptide entry inhibitors bind to the gp41 N-helical coiled-coil to form a peptide/protein hybrid structure and, in doing so, disrupt native six-helix bundle formation.
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29

Friedrich, Carol, Monisha G. Scott, Nedra Karunaratne, Hong Yan, and Robert E. W. Hancock. "Salt-Resistant Alpha-Helical Cationic Antimicrobial Peptides." Antimicrobial Agents and Chemotherapy 43, no. 7 (July 1, 1999): 1542–48. http://dx.doi.org/10.1128/aac.43.7.1542.

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ABSTRACT Analogues based on the insect cecropin–bee melittin hybrid peptide (CEME) were studied and analyzed for activity and salt resistance. The new variants were designed to have an increase in amphipathic α-helical content (CP29 and CP26) and in overall positive charge (CP26). The α-helicity of these peptides was demonstrated by circular dichroism spectroscopy in the presence of liposomes. CP29 was shown to have activity against gram-negative bacteria that was similar to or better than those of the parent peptides, and CP26 had similar activity. CP29 had cytoplasmic membrane permeabilization activity, as assessed by the unmasking of cytoplasmic β-galactosidase, similar to that of CEME and its more positively charged derivative named CEMA, whereas CP26 was substantially less effective. The activity of the peptides was not greatly attenuated by an uncoupler of membrane potential, carbonyl cyanide-m-chlorophenylhydrazone. The tryptophan residue in position 2 was shown to be necessary for interaction with cell membranes, as demonstrated by a complete lack of activity in the peptide CP208. Peptides CP29, CEME, and CEMA were resistant to antagonism by 0.1 to 0.3 M NaCl; however, CP26 was resistant to antagonism only by up to 160 mM NaCl. The peptides were generally more antagonized by 3 and 5 mM Mg2+ and by the polyanion alginate. It appeared that the positively charged C terminus in CP26 altered its ability to permeabilize the cytoplasmic membrane of Escherichia coli, although CP26 maintained its ability to kill gram-negative bacteria. These peptides are potential candidates for future therapeutic drugs.
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Arrighi, Romanico B. G., Chikashi Nakamura, Jun Miyake, Hilary Hurd, and J. Grant Burgess. "Design and Activity of Antimicrobial Peptides against Sporogonic-Stage Parasites Causing Murine Malarias." Antimicrobial Agents and Chemotherapy 46, no. 7 (July 2002): 2104–10. http://dx.doi.org/10.1128/aac.46.7.2104-2110.2002.

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ABSTRACT Insects produce several types of peptides to combat a broad spectrum of invasive pathogenic microbes, including protozoans. However, despite this defense response, infections are often established. Our aim was to design novel peptides that produce high rates of mortality among protozoa of the genus Plasmodium, the malaria parasites. Using existing antimicrobial peptide sequences as templates, we designed and synthesized three short novel hybrids, designated Vida1 to Vida3. Each has a slightly different predicted secondary structure. The peptides were tested against sporogonic stages of the rodent malaria parasites Plasmodium berghei (in vitro and in vivo) and P. yoelii nigeriensis (in vitro). The level of activity varied for each peptide and according to the parasite stage targeted. Vida3 (which is predicted to have large numbers of β sheets and coils but no α helices) showed the highest level of activity, killing the early sporogonic stages in culture and causing highly significant reductions in the prevalence and intensity of infection of P. berghei after oral administration or injection in Anopheles gambiae mosquitoes. The secondary structures of these peptides may play a crucial role in their ability to interact with and kill sporogonic forms of the malaria parasite.
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Yang, Yang, Di Wu, Chenxi Wang, Anshan Shan, Chongpeng Bi, Yanbing Li, and Wenping Gan. "Hybridization with Insect Cecropin A (1–8) Improve the Stability and Selectivity of Naturally Occurring Peptides." International Journal of Molecular Sciences 21, no. 4 (February 21, 2020): 1470. http://dx.doi.org/10.3390/ijms21041470.

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Antimicrobial peptides (AMPs) offer great hope and a promising opportunity to overcome the rapid development of drug-resistant pathogenic microbes. However, AMPs often lack the stability required for a successful systemic drug. Hybridizing different AMPs is a simple and effective strategy to obtain novel peptides. N-terminal fragment of cecropin A (CA (1-8)) is often used to hybridize with other AMPs to reduce cytotoxicity. However, hybridizing with CA (1-8) in improving the stability of AMPs is not clear. Therefore, a series of peptides were designed by combining with CA (1–8) and their antibacterial activity and stability in the presence of salts and human serum were evaluated. The resultant α-helical hybrid peptide CA-FO composed of CA (1-8) and the most potent region of Fowlicidin-2 (FO (1–15)) exhibited excellent antibacterial activity (2-8 μM) and cell selectivity toward bacterial over mammalian cells. Moreover, CA-FO still retained vigorous antimicrobial activity in the presence of human serum and salts at physiological concentrations. CA-FO exhibited effective antibacterial activity by increasing membrane permeability and damaging membrane integrity. In conclusion, these results indicated the success of hybridization in designing and optimizing AMPs with improved stability and selectivity and the peptide CA-FO can be further evaluated as peptide-therapy to treat bacterial infections.
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Marine, Jeannette E., Shuang Song, Xiaoli Liang, Matthew D. Watson, and Jonathan G. Rudick. "Bundle-forming α-helical peptide–dendron hybrid." Chemical Communications 51, no. 76 (2015): 14314–17. http://dx.doi.org/10.1039/c5cc05468k.

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33

Grammer, S. F., A. Sette, S. Colón, L. Walker, and R. Chesnut. "Identification of an HSV-1/HSV-2 cross-reactive T cell determinant." Journal of Immunology 145, no. 7 (October 1, 1990): 2249–53. http://dx.doi.org/10.4049/jimmunol.145.7.2249.

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Abstract The results from a number of studies have documented that the HSV glycoprotein gD is an important target for neutralizing antibodies. In contrast, little is known about the Th cell determinants present on HSV that are required for anti HSV gD antibody production. In our study we have immunized BALB/c mice with a recombinant source of HSV-1 gD lacking the carboxyl-terminal 93 amino acids. T cell hybridomas produced from the immunized animals recognized a single antigenic peptide (amino acids 246-261) in the context of I-Ad. The determinant expressed by gD peptide 246-261 was generated and presented by both HSV-1 and HSV-2 infected APC. Fine specificity analysis using truncated synthetic gD peptides revealed that the minimal amino acids recognized by the T hybrids were identical between HSV-1 and HSV-2. In addition, the minimal peptide-I-Ad binding analysis demonstrated that the minimal peptide sequence required for the binding to I-Ad and for T cell recognition contained two prolines. Thus, this important HSV antigenic determinant would not be expected to form an amphipathic alpha-helix and could therefore be missed by algorithms currently used to predict which amino acid sequences would be antigenic based on the propensity to form helices.
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34

Bateman, J. F., S. Lamande, D. Chan, and W. G. Cole. "Peptide analysis of collagen produced from cDNA by transcription and translation in vitro." Biochemical Journal 245, no. 2 (July 15, 1987): 393–98. http://dx.doi.org/10.1042/bj2450393.

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When collagen CNBr-cleavage peptides are analysed by two-dimensional gel electrophoresis each peptide is resolved into a reproducible set of charged forms. To test whether this peptide heterogeneity resulted from polymorphic mRNA, collagen was produced by transcription and translation in vitro of a collagen cDNA clone, and the peptides were mapped by two-dimensional gel electrophoresis. A cDNA construct was produced by ligation of the 5′ end of the rat phenylalanine hydroxylase cDNA [Dahl & Mercer (1986) J. Biol. Chem. 261, 4148-4153], containing the translation-initiation codon, to a human alpha 1(I) cDNA [Chu, Myers, Bernard, Ding & Ramirez (1982) Nucleic Acids Res. 10, 5925-5934] coding for a large portion of helical region including the complete CB7 and CB3 CNBr-cleavage peptides. This cDNA construct was ligated into the transcription vector pSP65, and cell-free translation of the mRNA transcribed from the pSP65 plasmid was performed with a rabbit reticulocyte lysate system. After CNBr cleavage of the hybrid protein translation products, the collagen CB7 and CB3 peptides were resolved by two-dimensional electrophoresis into the same multiple charged forms whether the mRNA was produced from the cDNA construct or was extracted from normal fibroblast cultures. This result demonstrated that the multiple peptide spots were not due to polymorphic mRNA species. The heterogeneity must result from some uncharacterized specific post-translational modification or chemical alterations during sample preparation. This method of expression and analysis of proteins from cDNA clones should be of considerable use in the identification and characterization of clones that code for mutant proteins.
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35

Honisch, Claudia, Eugenio Ragazzi, Rohanah Hussain, John Brazier, Giuliano Siligardi, and Paolo Ruzza. "Interaction of a Short Peptide with G-Quadruplex-Forming Sequences: An SRCD and CD Study." Pharmaceutics 13, no. 8 (July 21, 2021): 1104. http://dx.doi.org/10.3390/pharmaceutics13081104.

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G-quadruplex (G4) forming DNA sequences were recently found to play a crucial role in the regulation of genomic processes such as replication, transcription and translation, also related to serious diseases. Therefore, systems capable of controlling DNA and RNA G-quadruplex structures would be useful for the modulation of various cellular events. In particular, peptides represent good candidates for targeting G-quadruplex structures, since they are easily tailored to enhance their functionality. In this work, we analyzed, by circular dichroism and synchrotron radiation circular dichroism spectroscopies, the interaction of a 25-residue peptide deriving from RHAU helicases (Rhau25) with three G-quadruplex-forming oligonucleotide sequences, in both sodium- and potassium-containing buffers, the most relevant monovalent cations in physiological conditions. The peptide displayed greater affinity for the G4 sequences adopting a parallel structure. However, it showed the ability to also interact with antiparallel or hybrid G-quadruplex structures, inducing a conformation conversion to the parallel structure. The stability of the oligonucleotide structure alone or in presence of the Rhau25 peptide was studied by temperature melting and UV denaturation experiments, and the data showed that the interaction with the peptide stabilized the conformation of oligonucleotide sequences when subjected to stress conditions.
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36

Goch, G., H. Kozłowska, A. Wójtowicz, and A. Bierzyński. "A comparative CD and fluorescence study of a series of model calcium-binding peptides." Acta Biochimica Polonica 46, no. 3 (September 30, 1999): 673–77. http://dx.doi.org/10.18388/abp.1999_4139.

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Lanthanide-saturated peptides analogous to calcium-binding loops of EF-hand proteins can be used to stabilize the alpha-helical structure of peptide or protein segments attached to their C-termini. To study conformational properties of such loop-containing hybrids it is necessary to produce them in bacteria. In peptides obtained in this way the helix will be destabilized by the negatively charged C-terminal alpha-carboxyl groups. We propose to block them by the homoserine lactone. The results presented in this paper indicate that the presence of the lactone even at the C-terminus of the loop does not have any negative effect on the loop helix-nucleation ability. On the other hand, the presence of the alpha-NH3+ at the loop N-terminus leads to a drop of metal-binding constant and loss of the rigid structure of the alpha-helical segment of the loop. The alpha-amino group separated by one glycine residue from the loop N-terminus should also be avoided because it perturbs the conformation of the N-terminal part of the loop and may reduce the loop affinity to lanthanide ions.
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37

Kubo, T., and M. Fujii. "Interaction of cationic -helical peptide with phoshporothioate DNA hybrid." Nucleic Acids Symposium Series 42, no. 1 (November 1, 1999): 167–68. http://dx.doi.org/10.1093/nass/42.1.167.

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38

Johnsborg, Ola, Per Eugen Kristiansen, Trinelise Blomqvist, and Leiv Sigve Håvarstein. "A Hydrophobic Patch in the Competence-Stimulating Peptide, a Pneumococcal Competence Pheromone, Is Essential for Specificity and Biological Activity." Journal of Bacteriology 188, no. 5 (March 1, 2006): 1744–49. http://dx.doi.org/10.1128/jb.188.5.1744-1749.2006.

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ABSTRACT Induction of competence for natural genetic transformation in Streptococcus pneumoniae depends on pheromone-mediated cell-cell communication and a signaling pathway consisting of the competence-stimulating peptide (CSP), its membrane-embedded histidine kinase receptor ComD, and the cognate response regulator ComE. Extensive screening of pneumococcal isolates has revealed that two major CSP variants, CSP1 and CSP2, are found in members of this species. Even though the primary structures of CSP1 and CSP2 are about 50% identical, they are highly specific for their respective receptors, ComD1 and ComD2. In the present work, we have investigated the structural basis of this specificity by determining the three-dimensional structure of CSP1 from nuclear magnetic resonance data and comparing the agonist activity of a number of CSP1/CSP2 hybrid peptides toward the ComD1 and ComD2 receptors. Our results show that upon exposure to membrane-mimicking environments, the 17-amino-acid CSP1 pheromone adopts an amphiphilic α-helical configuration stretching from residue 6 to residue 12. Furthermore, the pattern of agonist activity displayed by the various hybrid peptides revealed that hydrophobic amino acids, some of which are situated on the nonpolar side of the α-helix, strongly contribute to CSP specificity. Together, these data indicate that the identified α-helix is an important structural feature of CSP1 which is essential for effective receptor recognition under natural conditions.
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39

Johansson, J., G. Nilsson, R. Strömberg, B. Robertson, H. Jörnvall, and T. Curstedt. "Secondary structure and biophysical activity of synthetic analogues of the pulmonary surfactant polypeptide SP-C." Biochemical Journal 307, no. 2 (April 15, 1995): 535–41. http://dx.doi.org/10.1042/bj3070535.

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Native pulmonary-surfactant-associated lipopolypeptide SP-C, its chemically depalmitoylated form and several synthetic analogues lacking the palmitoylcysteine residues were analysed for secondary structure in phospholipid micelles and for biophysical activity in 1,2-dipalmitoyl-sn-glycero-3- phosphocholine/phosphatidylglycerol/palmitic acid (68:22:9, by wt.). Compared with the native molecule, with the entire poly-valyl part in a known alpha-helical conformation, depalmitoylated SP-C was found to be still mainly alpha-helical, but with an approx. 20% decrease in the helical content. A synthetic hybrid polypeptide where the entire poly-valyl alpha-helical part of native SP-C had been replaced with the amino acid sequence of a transmembrane helix of bacteriorhodopsin is also predominantly alpha-helical. In contrast, synthetic SP-C analogues lacking only the palmitoyl groups, by replacement of the palmitoylcysteine residues with cysteine, phenylalanine or serine, or lacking the positively charged amino acids by replacement with alanine, are considerably less alpha-helical than both native and depalmitoylated SP-C. The data indicate that the SP-C palmitoyl groups are important for maintenance of the alpha-helical conformation in parts of the polypeptide, and that the poly-valyl alpha-helical conformation is not fully formed in synthetic SP-C polypeptides. Furthermore, the helical structure of both native and depalmitoylated SP-C in dodecylphosphocholine micelles is very resistant to thermal denaturation, exhibiting ordered structure at 90 degrees C. The alpha-helical content grossly parallels the peptide-induced acceleration of the spreading of phospholipids at an air/water interface and the increase of surface pressure. The data suggest that the alpha-helical conformation itself, rather than just the covalent structure, is of prime importance for the biological function of synthetic pulmonary-surfactant peptides.
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40

Dutta, Arpita, Suven Das, Purak Das, Suvendu Maity, Prasanta Ghosh, and Soumya Shankha Biswas. "Unique supramolecular assembly of a synthetic achiral α, γ-hybrid tripeptide." Zeitschrift für Kristallographie - Crystalline Materials 237, no. 1-3 (March 1, 2022): 77–81. http://dx.doi.org/10.1515/zkri-2022-0002.

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Abstract An achiral tripeptide, namely, Boc-γ-Abu-m-ABA-Aib-OMe (γ-Abu: γ−amino butyric acid; m-ABA: meta-aminobenzoic acid) was synthesized by solution phase procedure. The α, γ-hybrid peptide was designed in such a way that two dissimilar γ−amino acids, one flexible and another rigid, were positioned sidewise along with α-amino isobutyric acid (Aib) as C-terminal residue. The single crystal X-ray diffraction analysis revealed that two kinks were generated around centrally placed m-ABA. Interestingly, the peptide self-assembled via three intermolecular N–H···O and one intermolecular C–H···O hydrogen bonding interactions to supramlecular helical architecture.
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41

Smith, Jessica M., John R. Frost, and Rudi Fasan. "Designer macrocyclic organo-peptide hybrids inhibit the interaction between p53 and HDM2/X by accommodating a functional α-helix." Chem. Commun. 50, no. 39 (2014): 5027–30. http://dx.doi.org/10.1039/c4cc01199f.

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42

Rogers, Joseph M., Sunbum Kwon, Simon J. Dawson, Pradeep K. Mandal, Hiroaki Suga, and Ivan Huc. "Ribosomal synthesis and folding of peptide-helical aromatic foldamer hybrids." Nature Chemistry 10, no. 4 (March 19, 2018): 405–12. http://dx.doi.org/10.1038/s41557-018-0007-x.

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43

Ahmadi, Samaneh, Mohammad Bagher Shahsavani, Zohreh Tavaf, Rawayh Muslim Albaghlany, Ashutosh Kumar, Ali Akbar Moosavi-Movahedi, and Reza Yousefi. "A novel strategy for production of liraglutide precursor peptide and development of a new long-acting incretin mimic." PLOS ONE 17, no. 5 (May 2, 2022): e0266833. http://dx.doi.org/10.1371/journal.pone.0266833.

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Nowadays, a small number of incretin mimics are used to treat type 2 diabetes mellitus (T2DM) due to their longer half-life. The present study aimed to introduce a novel method for producing the liraglutide precursor peptide (LPP) and developing a potentially new incretin mimic. Here, human αB-crystallin (αB-Cry) was ligated to the LPP at the gene level, and the gene construct was expressed in Escherichia coli with a relatively good efficiency. The hybrid protein (αB-lir) was then purified by a precipitation method followed by anion exchange chromatography. After that, the peptide was released from the carrier protein by a chemical cleavage method yielding about 70%. The LPP was then purified by gel filtration chromatography, and HPLC estimated its purity to be about 98%. Also, the molecular mass of the purified peptide was finally confirmed by mass spectroscopy analysis. Assessment of the secondary structures suggested a dominant α-helical structure for the LPP and a β-sheet rich structure for the hybrid protein. The subcutaneous injection of the LPP and the αB-lir hybrid protein significantly reduced the blood sugar levels in healthy and diabetic mice and stimulated insulin secretion. Also, the hybrid protein exerts its bioactivities more effectively than the LPP over a relatively longer period of time. The results of this study suggested a novel method for the easy and cost-effective production of the LPP and introduced a new long-acting incretin mimic that can be potentially used for the treatment of T2DM patients.
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44

Malik, Ankita, Mothukuri Ganesh Kumar, Anupam Bandyopadhyay, and Hosahudya N. Gopi. "Helices with additional H-bonds: crystallographic conformations of α,γ-hybrid peptides helices composed of β-hydroxy γ-amino acids (statines)." Biopolymers 108, no. 1 (January 2017): e22978. http://dx.doi.org/10.1002/bip.22978.

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45

Tomizaki, Kin-ya, Yuichi Yamaguchi, Naoyuki Tsukamoto, and Takahito Imai. "α-Helical Peptide-Gold Nanoparticle Hybrids: Synthesis, Characterization, and Catalytic Activity." Protein & Peptide Letters 25, no. 1 (April 18, 2018): 56–63. http://dx.doi.org/10.2174/0929866525666171214113324.

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46

Barkley, Deborah A., Yekaterina Rokhlenko, Jeannette E. Marine, Rachelle David, Dipankar Sahoo, Matthew D. Watson, Tadanori Koga, Chinedum O. Osuji, and Jonathan G. Rudick. "Hexagonally Ordered Arrays of α-Helical Bundles Formed from Peptide-Dendron Hybrids." Journal of the American Chemical Society 139, no. 44 (October 24, 2017): 15977–83. http://dx.doi.org/10.1021/jacs.7b09737.

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47

Marine, Jeannette E., Shuang Song, Xiaoli Liang, and Jonathan G. Rudick. "Synthesis and Self-Assembly of Bundle-Forming α-Helical Peptide–Dendron Hybrids." Biomacromolecules 17, no. 1 (December 23, 2015): 336–44. http://dx.doi.org/10.1021/acs.biomac.5b01452.

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48

Rogers, Joseph M., Sunbum Kwon, Simon J. Dawson, Pradeep K. Mandal, Hiroaki Suga, and Ivan Huc. "Publisher Correction: Ribosomal synthesis and folding of peptide-helical aromatic foldamer hybrids." Nature Chemistry 10, no. 7 (May 31, 2018): 795. http://dx.doi.org/10.1038/s41557-018-0086-8.

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49

Zhang, Licong, Dandan Wei, Na Zhan, Taotao Sun, Bingdong Shan, and Anshan Shan. "Heterologous expression of the novel α-helical hybrid peptide PR-FO in Bacillus subtilis." Bioprocess and Biosystems Engineering 43, no. 9 (April 29, 2020): 1619–27. http://dx.doi.org/10.1007/s00449-020-02353-1.

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50

Balamurugan, Dhayalan, and Kannoth M. Muraleedharan. "Can Helical Peptides Unwind One Turn at a Time? - Controlled Conformational Transitions in α,β2,3-Hybrid Peptides." Chemistry - A European Journal 21, no. 26 (May 15, 2015): 9332–38. http://dx.doi.org/10.1002/chem.201501198.

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