Threefold Axis Research Articles

First-principles theoretical analysis of magnetically tunable topological semimetallic states in antiferromagnetic DyPdBi

A number of compounds in the family of rare-earth half-Heusler alloys have been predicted to be topologically nontrivial semimetals, classified as Weyl, triple-point, and Dirac semimetals based on the multiplicity of degeneracy of the nodal points or crossing of linearly dispersed electronic bands. Here, we present a first-principles theoretical characterization of the electronic topology of the antiferromagnetic half-Heusler alloy DyPdBi. In the antiferromagnetic state preserving ${C}_{3v}$ symmetry of the crystal, DyPdBi is a triple-point semimetal hosting four triply degenerate nodes along the threefold symmetry axis of the Brillouin zone. In contrast, the antiferromagnetic state of DyPdBi with local magnetic moments on Dy rotated to a direction perpendicular to the ${C}_{3}$ axis breaks the threefold rotational symmetry, and hosts four Weyl nodes in its Brillouin zone. Our calculations of the Berry curvature of their electronic states clearly show that the triple-point fermions of DyPdBi exhibit a signature peak in the anomalous Hall conductivity, while the Weyl fermions do not contribute to anomalous Hall conductivity. As these two topologically distinct magnetic states are separated by a small energy difference of $\ensuremath{\approx}$15 meV, we expect them to be switchable with a magnetic field or spin torque and distinguishable experimentally from anomalous Hall conductance.

Solvent-mediated precipitating synthesis and optical properties of polyhydrido Cu13 nanoclusters with four vertex-sharing tetrahedrons.

Structurally defined metal nanoclusters facilitate mechanism studies and promote functional applications. However, precisely constructing copper nanoclusters remains a long-standing challenge in nanoscience. Developing new efficient synthetic strategies for Cu nanoclusters is highly desirable. Here, we propose a solvent-mediated precipitating synthesis (SMPS) to prepare Cu13H10(SR)3(PPh3)7 nanoclusters (H-SR = 2-chloro-4-fluorobenzenethiol). The obtained Cu13 nanoclusters are high purity and high yield (39.5%, based on Cu atom), proving the superiority of the SMPS method. The Cu13 nanoclusters were comprehensively studied via a series of characterizations. Single crystal X-ray crystallography shows that the Cu13 nanoclusters contain a threefold symmetry axis and the Cu13 kernel is protected by a monolayer of ligands, including PPh3 and thiolates. Unprecedentedly, the aesthetic Cu13 kernel is composed of four vertex-sharing tetrahedrons, rather than the common icosahedral or cuboctahedral M13. The intramolecular π⋯π interactions between thiolates and PPh3 on the surface contribute to the stable configuration. Furthermore, electrospray ionization mass spectrometry (ESI-MS) and nuclear magnetic resonance (NMR) revealed the existence of ten hydrides, including four types of hydrides. Density functional theory (DFT) calculations without simplifying the ligands simulated the location of the 10 hydrides in the crystal structure. Additionally, the steady-state ultraviolet-visible absorption and fluorescence spectra of the Cu13 nanoclusters exhibit unique optical absorbance and photoluminescence. The ultrafast relaxation dynamics were also studied via transient absorption spectroscopy, and the three decay components are attributed to the relaxation pathways of internal conversion, structural relaxation and radiative relaxation. This work provides not only a novel SMPS strategy to efficiently synthesize Cu13 nanoclusters, but also a better insight into the structural characteristics and optical properties of the Cu nanoclusters.

Identification of the Intrinsic Motions and Related Key Residues Responsible for the Twofold Channel Opening of Poliovirus Capsid by Using an Elastic Network Model Combined with an Internal Coordinate.

Poliovirus (PV) is an infectious virus that causes poliomyelitis, which seriously threatens the health of children. The release of viral RNA is a key step of PV in host cell infection, and multiple lines of evidence have demonstrated that RNA release is initiated by the opening of the twofold channels of the PV capsid. However, the mechanism that controls the twofold channel opening is still not well understood. In addition, the channel opening motion of the recombinant PV capsid leads to the destruction of predominant neutralizing epitopes and thus hinders the capsid as a vaccine immunogen. Therefore, it is important to identify the intrinsic motions and the related key residues controlling the twofold channel opening for understanding the virus infection mechanism and developing capsid-based vaccines. In the present work, the width of the channel was selected as an internal coordinate directly related to the channel opening, and then the elastic network model (ENM) combined with the group theory were employed to extract the intrinsic motion modes that mostly contribute to the opening of the twofold channels. Our results show that the channel opening predominately induced by the breathing motion and the overall rotation of each protomer in the capsid. Then, an internal coordinate-based perturbation method was used to identify the key residues regulating the twofold channel opening of PV. The calculation results showed that the predicted key residues are mainly located at the twofold axes, the bottom of the canyons and the quasi threefold axes. Our study is helpful for better understanding the twofold channel opening mechanism and provides a potential target for preventing the opening of the channels, which is of great significance for PV vaccine design. The source code of this study is available at https://github.com/SJGLAB/CapsidKeyRes.git.

Mixed-valent 1:1 oxidotellurates(IV/VI) of Na, K and Rb: superstructure and three-dimensional disorder

Abstract Single crystals of three mixed-valent oxidotellurates(IV/VI) with general formula M 2TeIVTeVIO6 (H2O) x (M = Na, K, Rb) were grown under hydrothermal conditions at 210 °C from M 2CO3, TeO2 and Te(OH)6 in a 4:1:1 molar ratio. Na2Te2O6·11/8H2O (where TeIVTeVI is abbreviated as Te2) crystallizes as a monoclinic eightfold superstructure with occupational modulation of the water molecules. The structure is built of diperiodic corrugated [Te2O6]2− networks interleaved by the Na atoms and H2O molecules. The hexagonal crystal structures of M 2Te2O4(OH)4 (M = K, Rb; x = 2) with P63/mmc symmetry are made up of [Te2O4(OH)4]2− rods extending in the [001] direction. The rods are connected by the M atoms. The [TeIVO2(OH)2] units are disordered about the threefold axis, resulting in pronounced three-dimensional diffuse scattering.

Dynamic HIV-1 spike motion creates vulnerability for its membrane-bound tripod to antibody attack

Vaccines targeting HIV-1’s gp160 spike protein are stymied by high viral mutation rates and structural chicanery. gp160’s membrane-proximal external region (MPER) is the target of naturally arising broadly neutralizing antibodies (bnAbs), yet MPER-based vaccines fail to generate bnAbs. Here, nanodisc-embedded spike protein was investigated by cryo-electron microscopy and molecular-dynamics simulations, revealing spontaneous ectodomain tilting that creates vulnerability for HIV-1. While each MPER protomer radiates centrally towards the three-fold axis contributing to a membrane-associated tripod structure that is occluded in the upright spike, tilting provides access to the opposing MPER. Structures of spike proteins with bound 4E10 bnAb Fabs reveal that the antibody binds exposed MPER, thereby altering MPER dynamics, modifying average ectodomain tilt, and imposing strain on the viral membrane and the spike’s transmembrane segments, resulting in the abrogation of membrane fusion and informing future vaccine development.

Cover Feature: A Homoleptic Diphosphatetrahedrane Nickel(0) Complex (Z. Anorg. Allg. Chem. 19/2022)

A three-bladed windmill illustrates the molecular structure of the title complex tris(diphosphatetrahedrane)nickel(0). The three sails of the windmill represent the three diphosphatetrahedrane molecules, which coordinate via their P–P bonds to a single nickel(0) atom forming the windshaft. The three blades illustrate the threefold rotation axis of the complex and the propeller twist of the ligands, which makes the complex chiral.(DOI: 10.1002/zaac.202200124).

Targeting the lung epithelium after intravenous delivery by directed evolution of underexplored sites on the AAV capsid

Advances in adeno-associated virus (AAV) engineering have provided exciting new tools for research and potential solutions for gene therapy. However, the lung has not received the same tailored engineering as other major targets of debilitating genetic disorders. To address this, here we engineered the surface-exposed residues AA452-458 of AAV9 capsid proteins at the three-fold axis of symmetry and employed a Cre-transgenic-based screening platform to identify AAV capsids targeted to the lung after intravenous delivery in mice. Using a custom image processing pipeline to quantify transgene expression across whole tissue images, we found that one engineered variant, AAV9.452sub.LUNG1, displays dramatically improved transgene expression in lung tissue after systemic delivery in mice. This improved transduction extends to alveolar epithelial type II cells, expanding the toolbox for gene therapy research for diseases specific to the lung.

Crystal structure of fulvestrant hydrate (ethyl acetate), C32H47F5O3S(H2O)0.16(C4H8O2)0.025

The crystal structure of fulvestrant hydrate (ethyl acetate) has been solved and refined using synchrotron X-ray powder diffraction data, and optimized using density functional theory techniques. This solvate of fulvestrant crystallizes in space group R3 (#146) with a = 23.39188(16), c = 16.50885(13) Å, V = 7823.08(7) Å3, and Z = 9. The crystal structure is composed of triangular hydrogen-bonded chains of molecules around one of the threefold axes. The fluorinated ends of the molecules cluster around another threefold axis. Voids around a threefold axis occupy 8.1% of the unit cell volume, and are partially occupied by the water and ethyl acetate molecules. Both hydroxyl groups act as donors in O–H⋯O hydrogen bonds. These H-bonds form a large ring. The powder pattern has been submitted to ICDD® for inclusion in the Powder Diffraction File™ (PDF®).

A new perspective on the evolution and diversity of the genus Amdoparvovirus (family Parvoviridae) through genetic characterization, structural homology modeling, and phylogenetics.

Amdoparvoviruses (genus Amdoparvovirus, family Parvoviridae) are primarily viruses of carnivorans, but recent studies have indicated that their host range might also extend to rodents and chiropterans. While their classification is based on the full sequence of the major nonstructural protein (NS1), several studies investigating amdoparvoviral diversity have been focused on partial sequences, leading to difficulties in accurately determining species demarcations and leaving several viruses unclassified. In this study, while reporting the complete genomic sequence of a novel amdoparvovirus identified in an American mink (British Columbia amdoparvovirus, BCAV), we studied the phylogenetic relationships of all amdoparvovirus-related sequences and provide a comprehensive reevaluation of their diversity and evolution. After excluding recombinant sequences, phylogenetic and pairwise sequence identity analyses allowed us to define fourteen different viruses, including the five currently classified species, BCAV, and four additional viruses that fulfill the International Committee on Taxonomy of Viruses criteria to be classified as species. We show that the group of viruses historically known as Aleutian mink disease virus (species Carnivore amdoparvovirus 1) should be considered as a cluster of at least four separate viral species that have been co-circulating in mink farms, facilitating the occurrence of inter-species recombination. Genome organization, splicing donor and acceptor sites, and protein sequence motifs were surprisingly conserved within the genus. The sequence of the major capsid protein virus protein 2 (VP2) was significantly more conserved between and within species compared to NS1, a phenomenon possibly linked to antibody-dependent enhancement (ADE). Homology models suggest a remarkably high degree of conservation of the spikes located near the icosahedral threefold axis of the capsid, comprising the surface region associated with ADE. A surprisingly high number of divergent amino acid positions were found in the luminal threefold and twofold axes of the capsid, regions of hitherto unknown function. We emphasize the importance of complete genome analyses and, given the marked phylogenetic inconsistencies across the genome, advise to obtain the complete coding sequences of divergent strains. Further studies on amdoparvovirus biology and structure as well as epidemiological and virus discovery investigations are required to better characterize the ecology and evolution of this important group of viruses.

The Acetyltransferase RibT From Bacillus subtilis Affects in vivo Dynamics of the Multimeric Heavy Riboflavin Synthase Complex.

Flavins are ubiquitous molecules in life as they serve as important enzyme cofactors. In the Gram-positive, soil-dwelling bacterium Bacillus subtilis, four well-characterized gene products (the enzymes RibDG, RibE, RibAB, and RibH) catalyze the biosynthesis of riboflavin (RF) from guanosine-triphosphate (GTP) and ribulose-5-phosphate (R5P). The corresponding genes form an operon together with the gene ribT (ribDG-E-AB-H-T), wherein the function of this terminal gene remained enigmatic. RibT has been structurally characterized as a GCN5-like acetyltransferase (GNAT), however, with unidentified target molecules. Bacterial two-hybrid system revealed interactions between RibT, RibH, and RibE, forming the heavy RF synthase complex. Applying single particle tracking (SPT), we found that confined (sub)diffusion of RibT is largely dependent on interacting RibE and, to a lesser degree, on interacting RibH. By induced expression of otherwise low-expressed ribT from an ectopic locus, we observed a decrease in the subpopulation considered to represent capsids of the heavy RF synthase and an increase in the subpopulation thought to represent pentamers of RibH, pointing to a putative role for RibT in capsid disassembly. Complementarily, either deletion of ribT or mutation of a key residue from RibH (K29) suspected to be the substrate of RibT for acetylation leads to increased levels of subpopulations considered as capsids of RibH-mVenus (RibH-mV) in comparison to wild-type (wt)-like cells. Thus, we provide evidence for an indirect involvement of RibT in RF biosynthesis by a putative capsid disassembling mechanism considered to involve acetylation of RibH residue K29 at the three-fold symmetry axis of 60-mer capsids.

Effects of crystalline anisotropy on resonant acoustic loss of torsional quartz viscometers.

Vibrational modes of unrestrained elastic cylinders of trigonal crystals are studied using Ritz-based polynomial approximations for displacements formulated in rectangular Cartesian coordinates. The selected orientation of the threefold trigonal axis is perpendicular to the cylinder axis, corresponding to the configuration employed in torsional quartz viscometry (TQV) for characterizing Newtonian fluids. A revised working equation for TQV is derived, incorporating effects of crystalline anisotropy, and Ritz results are used to numerically quantify effects of acoustic radiation from surface-normal displacements and viscous loss from nontorsional surface-parallel displacements of resonant modes corresponding to the purely torsional modes of isotropic cylinders traditionally employed as an approximation in TQV analysis. For a cylinder typical of TQV, with 3 mm diameter and 50 mm length, the anisotropy-related correction to the extracted fluid viscosity is a positive shift of 36 ppm relative to the isotropic approximation, if radiative losses are neglected. This contribution is independent of fluid properties. Radiative losses depend on the properties of the fluid and reduce the extracted viscosity. The total magnitude of corrections varies between several tens of parts per million for low density gases to values on the order of 0.01% for normal liquids near atmospheric pressure and 0.06% for superfluid helium.

Epitaxial growth of bilayer Bi(110) on two-dimensional ferromagnetic Fe3GeTe2

Heterostructures of two-dimensional (2D) layered materials with selective compositions play an important role in creating novel functionalities. Effective interface coupling between 2D ferromagnet and electronic materials would enable the generation of exotic physical phenomena caused by intrinsic symmetry breaking and proximity effect at interfaces. Here, epitaxial growth of bilayer Bi(110) on 2D ferromagnetic Fe3GeTe2 (FGT) with large magnetic anisotropy has been reported. Bilayer Bi(110) islands are found to extend along fixed lattice directions of FGT. The six preferred orientations could be divided into two groups of three-fold symmetry axes with the difference approximately to 26°. Moreover, dI/dV measurements confirm the existence of interface coupling between bilayer Bi(110) and FGT. A variation of the energy gap at the edges of bilayer Bi(110) is also observed which is modulated by the interface coupling strengths associated with its buckled atomic structure. This system provides a good platform for further study of the exotic electronic properties of epitaxial Bi(110) on 2D ferromagnetic substrate and promotes potential applications in the field of spin devices.

Synthesis and X-ray-graphical characteristics of the MеSn<sub>2</sub>F<sub>5</sub> (Mе = Na, K, Rb, Cs) fluoride-ion conductors

Objectives. Pentafluorodistannates of alkali metals are promising materials for use as electrolytes in fluoride-ion batteries due to their electrophysical properties, such as high fluoride-ion conductivity. This work aims to synthesize crystals of alkali metals MeSn2F5 (Me = Na, K, Rb, Cs), carry out X-ray diffraction studies on them, and investigate the possibility of obtaining lithium fluorostannates.Methods. Supersaturated aqueous solutions were employed to synthesize the crystals. The X-ray diffraction (XRD) analysis was carried out.Results. Oversaturated solutions yield microcrystalline powders of sodium, potassium, rubidium, and cesium pentafluorodistannates. The presence of a single-phase was confirmed by XRD analysis of the powders corresponding to the MеSn2F5 (Mе = Na, K, Rb, Cs) composition. XRD data analysis and literature indicated that MеSn2F5 (Mе = K, Rb, Cs) have a fluorite-like structure, with the cations forming three-layer closest packing. The RbSn2F5 compound was discovered to be isostructural to KSn2F5. Based on this discovery, RbSn2F5 was reindexed to a hexagonal unit cell with parameters a = 7.40(3) Å, с = 10.12(6) Å (KSn2F5 P3, a = 7.29(3) Å, с = 9.86(2) Å). The CsSn2F5 compound was reindexed to a monoclinic unit cell (a = 10.03(4) Å, b = 5.92(7) Å, c = 11.96(9) Å, β = 107.4(5)°). A crystallochemical analysis of the pentafluorodistannates was carried out, and common structural motifs were discovered. The motifs are similar to lead tetrafluorostannate PbSnF4, the best fluoride-ion conductor. The effect of the pentafluorodistannates structures on the ionic conductivity is considered. The LiF–SnF2 system contains no compounds; the compositions were obtained by melting the original fluorides. Conclusions. MеSn2F5 (Mе = Na, K, Rb, Cs) were synthesized and investigated by XRD analysis. The structural characteristics of the RbSn2F5 and CsSn2F5 compounds have been redefined. The crystallochemical structure is analyzed in relation to the electrophysical properties of the alkali metal pentafluorodistannates. Pentafluorodistannates MеSn2F5 (Mе = K, Rb, Cs) have a fluorite-like structural motif with cubic parameters а = 5.694 Å (KSn2F5), а = 5.846 Å (RbSn2F5), а = 6.100 Å (CsSn2F5), with the cations forming three-layer closest packing. The cationic layers alternate like Me–Sn–Sn–Me (Mе = K, Rb, Cs). For KSn2F5 and RbSn2F5, they are normal to the three-fold axis and normal to the four-fold axis in the case of CsSn2F5.

Key carboxylate residues for iron transit through the prokaryotic ferritin SynFtn.

Ferritins are proteins forming 24meric rhombic dodecahedral cages that play a key role in iron storage and detoxification in all cell types. Their function requires the transport of Fe2+ from the exterior of the protein to buried di-iron catalytic sites, known as ferroxidase centres, where Fe2+ is oxidized to form Fe3+-oxo precursors of the ferritin mineral core. The route of iron transit through animal ferritins is well understood: the Fe2+ substrate enters the protein via channels at the threefold axes and conserved carboxylates on the inner surface of the protein cage have been shown to contribute to transient binding sites that guide Fe2+ to the ferroxidase centres. The routes of iron transit through prokaryotic ferritins are less well studied but for some, at least, there is evidence that channels at the twofold axes are the major route for Fe2+ uptake. SynFtn, isolated from the cyanobacterium Synechococcus CC9311, is an atypical prokaryotic ferritin that was recently shown to take up Fe2+ via its threefold channels. However, the transfer site carboxylate residues conserved in animal ferritins are absent, meaning that the route taken from the site of iron entry into SynFtn to the catalytic centre is yet to be defined. Here, we report the use of a combination of site-directed mutagenesis, absorbance-monitored activity assays and protein crystallography to probe the effect of substitution of two residues potentially involved in this pathway. Both Glu141 and Asp65 play a role in guiding the Fe2+ substrate to the ferroxidase centre. In the absence of Asp65, routes for Fe2+ to, and Fe3+ exit from, the ferroxidase centre are affected resulting in inefficient formation of the mineral core. These observations further define the iron transit route in what may be the first characterized example of a new class of ferritins peculiar to cyanobacteria.

Crystal structure of the potato leafroll virus coat protein and implications for viral assembly

Luteoviruses, poleroviruses, and enamoviruses are insect-transmitted, agricultural pathogens that infect a wide array of plants, including staple food crops. Previous cryo-electron microscopy studies of virus-like particles show that luteovirid viral capsids are built from a structural coat protein that organizes with T = 3 icosahedral symmetry. Here, we present the crystal structure of a truncated version of the coat protein monomer from potato leafroll virus at 1.80-Å resolution. In the crystal lattice, monomers pack into flat sheets that preserve the two-fold and three-fold axes of icosahedral symmetry and show minimal structural deviations when compared to the full-length subunits of the assembled virus-like particle. These observations have important implications in viral assembly and maturation and suggest that the CP N-terminus and its interactions with RNA play an important role in generating capsid curvature.

High-Throughput Discovery of a Rhombohedral Twelve-Connected Zirconium-Based Metal-Organic Framework with Ordered Terephthalate and Fumarate Linkers.

We report a metal‐organic framework where an ordered array of two linkers with differing length and geometry connect [Zr6(OH)4O4]12+ clusters into a twelve‐connected fcu net that is rhombohedrally distorted from cubic symmetry. The ordered binding of equal numbers of terephthalate and fumarate ditopic carboxylate linkers at the trigonal antiprismatic Zr6 core creates close‐packed layers of fumarate‐connected clusters that are connected along the single remaining threefold axis by terephthalates. This well‐defined linker arrangement retains the three‐dimensional porosity of the Zr cluster‐based UiO family while creating two distinct windows within the channels that define two distinct guest diffusion paths. The ordered material is accessed by a restricted combination of composition and process parameters that were identified by high‐throughput synthesis.

High‐Throughput Discovery of a Rhombohedral Twelve‐Connected Zirconium‐Based Metal‐Organic Framework with Ordered Terephthalate and Fumarate Linkers

AbstractWe report a metal‐organic framework where an ordered array of two linkers with differing length and geometry connect [Zr6(OH)4O4]12+ clusters into a twelve‐connected fcu net that is rhombohedrally distorted from cubic symmetry. The ordered binding of equal numbers of terephthalate and fumarate ditopic carboxylate linkers at the trigonal antiprismatic Zr6 core creates close‐packed layers of fumarate‐connected clusters that are connected along the single remaining threefold axis by terephthalates. This well‐defined linker arrangement retains the three‐dimensional porosity of the Zr cluster‐based UiO family while creating two distinct windows within the channels that define two distinct guest diffusion paths. The ordered material is accessed by a restricted combination of composition and process parameters that were identified by high‐throughput synthesis.

Engineering Chemisorption of Fe4 Single‐Molecule Magnets on Gold

AbstractGaining control over the grafting geometry is critically important for any application of surface‐supported single‐molecule magnets (SMMs) in data storage, spintronics, and quantum information science. Here, tetrairon(III) SMMs with a propeller‐like structure are functionalized with thioacetyl‐terminated alkyl chains to promote chemisorption on gold surfaces from solution and to evaluate differences in adsorption geometry and magnetic properties as a function of chain length. The prepared monolayers are investigated using X‐ray absorption techniques with linearly and circularly polarized light to extract geometrical and magnetic information, respectively. All derivatives remain intact and form partially oriented monolayers on the gold surface. A ligand‐field analysis of the observed X‐ray natural linear dichroism shows that the threefold molecular axis is invariably biased toward the surface normal, in agreement with ab initio calculations. This preferential orientation is most pronounced in monolayers of the shortest‐chain derivative, which are further studied with an ultralow temperature X‐ray magnetic circular dichroism setup operating down to 350 mK. The isothermal field sweeps with the magnetic field at normal incidence show an open hysteresis loop below 1 K, while measurements at different incidence angles prove the magnetic anisotropy of the monolayers.

Synthesis and structure determination of racemic (Δ/Λ)-tris-(ethyl-enedi-amine)-cobalt(III) trichloride hemi(hexa-aqua-sodium chloride).

The synthesis and crystal structure of the title racemic compound, [Co(C2H8N2)3]Cl3.{[Na(H2O)6]Cl}0.5, are reported. The trivalent cobalt atom, which resides on a crystallographic threefold axis, is chelated by a single ethyl-ene di-amine (en) ligand and yields the tris-chelate [Co(en)3]3+ cation with distorted octa-hedral geometry after the application of crystal symmetry. The sodium cation (site symmetry ), has a single water mol-ecule bound to it in the asymmetric unit and yields a distorted, octa-hedrally coordinated hydrated [Na(H2O)6]+ cation after the application of symmetry. One of the chloride ions lies on a general position and the other has site symmetry. An extensive array of C-H⋯O, N-H⋯Cl and O-H⋯Cl hydrogen bonds exists between the ethyl-ene di-amine ligands, the water mol-ecules of hydration, and the anions present, thereby furnishing solid-state stability.

Discovery of a readily heterologously expressed Rubisco from the deep sea with potential for CO2 capture

Ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco), the key CO2-fixing enzyme in photosynthesis, is notorious for its low carboxylation. We report a highly active and assembly-competent Form II Rubisco from the endosymbiont of a deep-sea tubeworm Riftia pachyptila (RPE Rubisco), which shows a 50.5% higher carboxylation efficiency than that of a high functioning Rubisco from Synechococcus sp. PCC7002 (7002 Rubisco). It is a simpler hexamer with three pairs of large subunit homodimers around a central threefold symmetry axis. Compared with 7002 Rubisco, it showed a 3.6-fold higher carbon capture efficiency in vivo using a designed CO2 capture model. The simple structure, high carboxylation efficiency, easy heterologous soluble expression/assembly make RPE Rubisco a ready-to-deploy enzyme for CO2 capture that does not require complex co-expression of chaperones. The chemosynthetic CO2 fixation machinery of chemolithoautotrophs, CO2-fixing endosymbionts, may be more efficient than previously realized with great potential for next-generation microbial CO2 sequestration platforms.