Structure and stability of the designer protein WRAP-T and its permutants

Abstract$$\beta $$ β -Propeller proteins are common natural disc-like pseudo-symmetric proteins that contain multiple repeats (‘blades’) each consisting of a 4-stranded anti-parallel $$\beta $$ β -sheet. So far, 4- to 12-bladed $$\beta $$ β -propellers have been discovered in nature showing large functional and sequential variation. Using computational design approaches, we created perfectly symmetric $$\beta $$ β -propellers out of natural pseudo-symmetric templates. These proteins are useful tools to study protein evolution of this very diverse fold. While the 7-bladed architecture is the most common, no symmetric 7-bladed monomer has been created and characterized so far. Here we describe such a engineered protein, based on a highly symmetric natural template, and test the effects of circular permutation on its stability. Geometrical analysis of this protein and other artificial symmetrical proteins reveals no systematic constraint that could be used to help in engineering of this fold, and suggests sequence constraints unique to each $$\beta $$ β -propeller sub-family.

Structure and Stability of the designer protein WRAP-T and its permutants

β-propeller proteins are common natural disc-like pseudo-symmetric proteins that contain multiple repeats ('blades') each consisting of a 4-stranded anti-parallel beta-sheet. So far, 4- to 12-bladed β-propellers have been discovered in nature showing large functional and sequential variation. Using computational design approaches, we created perfectly symmetric β-propellers out of natural pseudo-symmetric templates. These proteins are useful tools to study protein evolution of this very diverse fold. While the 7-bladed architecture is the most common, no symmetric 7-bladed monomer has been created and characterized so far. Here we describe such a engineered protein, based on a highly symmetric natural template, and test the effects of circular permutation on its stability. Geometrical analysis of this protein and other artificial symmetrical proteins reveals no systematic constraint that could be used to help in engineering of this fold, and suggests sequence constraints unique to each β-propeller sub-family.

Natural template derived porous carbon nanoplate architectures with tunable pore configuration for a full-carbon sodium-ion capacitor

Sodium-ion capacitors (SICs) combine the advantages of sodium-ion batteries and supercapacitors and have been regarded as one of the promising electrochemical energy storage devices. However, the electrochemical performance of SICs...

Polymerase γ efficiently replicates through many natural template barriers but stalls at the HSP1 quadruplex

Faithful replication of the mitochondrial genome is carried out by a set of key nuclear-encoded proteins. DNA polymerase γ is a core component of the mtDNA replisome and the only replicative DNA polymerase localized to mitochondria. The asynchronous mechanism of mtDNA replication predicts that the replication machinery encounters dsDNA and unique physical barriers such as structured genes, G-quadruplexes, and other obstacles. In vitro experiments here provide evidence that the polymerase γ heterotrimer is well-adapted to efficiently synthesize DNA, despite the presence of many naturally occurring roadblocks. However, we identified a specific G-quadruplex–forming sequence at the heavy-strand promoter (HSP1) that has the potential to cause significant stalling of mtDNA replication. Furthermore, this structured region of DNA corresponds to the break site for a large (3,895 bp) deletion observed in mitochondrial disease patients. The presence of this deletion in humans correlates with UV exposure, and we have found that efficiency of polymerase γ DNA synthesis is reduced after this quadruplex is exposed to UV in vitro.

Effect of Geraniol and Citronellol Essential Oils on the Biophysical Gating Properties of AMPA Receptors

Essential oils have been advertised endlessly to be very beneficial for the health of humans, and an extensive amount of research examines the validity of such claims. In contribution, the current study evaluates the neuroprotective properties of Citronellol and Geraniol essential oils (EOs). In relationship to the biophysical gating properties of different the α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor (AMPAR) subunits, the EOs were administered to HEK293 (Human embryonic kidney 293) cells and examined for any inhibition and effect on desensitization or deactivation rates, using whole-cell patch-clamp electrophysiology. Our results demonstrated the highest levels of inhibition from Citronellol oil by four-fold on all AMPARs subunits. Likewise, Geraniol oil had a similar inhibiting impact on the receptors, and both oils decreased the desensitization and deactivation rates of the inhibited receptors. Thus, the examined EOs of this study portray neuroprotective qualities by targeting AMPARs activation and reducing desensitization and deactivation rates. Finally, the results of the current study entail a better understanding of AMPARs, provides a natural template for future drug synthesis to treat neurological diseases associated with excessive AMPAR activation, and offers a possible mechanism by which these essential oils deploy their ‘calming’ effect.

Preparation and heat-insulating properties of Al2O3–ZrO2(Y2O3) hollow fibers derived from cogon using an orthogonal experimental design

Lightweight Al2O3–ZrO2(Y2O3) hollow fibers with low thermal conductivity were prepared by a natural template—cogon grass.