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Homogentisate solanesyltransferase (HST) is a crucial enzyme in the plastoquinone biosynthetic pathway and has recently emerged as a promising target for herbicides. In this study, we successfully expressed and purified a stable and highly pure form of seven times transmembrane protein Chlamydomonas reinhardtii HST (CrHST). The final yield of CrHST protein obtained was 12.2 mg per liter of M9 medium. We evaluated the inhibitory effect on CrHST using Des-Morpholinocarbony Cyclopyrimorate (DMC) and found its IC50 value to be 3.63 ± 0.53 μM, indicating significant inhibitory potential. Additionally, we investigated the substrate affinity of CrHST with two substrates, determining the Km values as 22.76 ± 1.70 μM for FPP and 48.54 ± 3.89 μM for HGA. Through sequence alignment analyses and three-dimensional structure predictions, we identified conserved amino acid residues forming the active cavity in the enzyme. The results from molecular docking and binding energy calculations indicate that DMC has a greater binding affinity with HST compared to HGA. These findings represent substantial progress in understanding CrHST's properties and potential for herbicide development. Key points: • First high-yield transmembrane CrHST protein via E. coli system • Preliminarily identified active cavity composition via activity testing • Determined substrate and inhibitor modes via molecular docking [ABSTRACT FROM AUTHOR]

Abstract: Two copper(II)/cobalt(II) coordination polymers formulated as [Co(3-bptzp)(1,4-BDC)(1,4-H2BDC)0.5] (1) and [Cu(3-bptzp)(1,4-BDC)] (2) have been hydrothermally synthesized by using a flexible bis(pyridyl-tetrazole) ligand (3-bptzp = 1,4-bis(5-(3-pyridyl)tetrazolyl)propane) and an aromatic dicarboxylic acid (1,4-H2BDC = 1,4-benzenedicarboxylic acid) as mixed ligands. Both complexes have been characterized by single-crystal X-ray diffraction, elemental analyses, infrared spectroscopy and powder X-ray diffraction. There are two different types of 2D layered network in the structures of both complexes. In complex 1, the 2D layered network is formed by 1,4-BDC anions and neutral 1,4-H2BDC ligands, while the 3-bptzp ligands bridge the adjacent two Co(II) atoms to form a [Co2(3-bptzp)2] ring. In complex 2, adjacent Cu(II) atoms are bridged by 1,4-BDC anions to form a 1D [Cu(1,4-BDC)]n chain, and then adjacent 1D [Cu(1,4-BDC)]n chains are further linked together by the 3-bptzp ligands to generate a 2D layered network. The electrochemical behaviors and dye adsorption properties of both complexes have been studied.Graphical Abstract: Two new coordination polymers constructed from a flexible bis(pyridyl-tetrazole) ligand have been hydrothermally synthesized. There exist two different types of 2D layered structures in the complexes 1 and 2. In addition, the electrochemical behaviors and dye adsorption properties of complexes 1-2 have been studied. [ABSTRACT FROM AUTHOR]

Three polyoxometalate-based metal-organic complexes [Co(HO)(TeMoO)](3-Hdpyb)·2HO ( 1), [M(4-Hdpyb)(HO)(TeMoO)]·6HO [M = Co ( 2), Zn ( 3); 3-dpyb = N, N′-bis(3-pyridinecarboxamide)-1,4-butane, 4-dpyb = N, N′-bis(4-pyridinecarboxamide)-1,4-butane] have been hydrothermally synthesized and characterized by elemental analysis, IR, TG, powder diffraction and single-crystal X-ray diffraction analysis. The structure of complex 1 consists of 1D [Co(HO)(TeMoO)] inorganic chains, which are joined together by the 3-dpyb ligands through weak hydrogen bonds to generate a 2D supramolecular network. Complexes 2 and 3 are isostructural; each [TeMoO] (TeMo) polyoxoanion chelates either two cobalt or two zinc atoms to generate the discrete complexes [Co(4-Hdpyb)(HO)(TeMoO)] and [Zn(4-Hdpyb)(HO)(TeMoO)], respectively. The electrochemical properties, electrocatalytic and photocatalytic activities of the complexes have been investigated. [ABSTRACT FROM AUTHOR]

Two different Anderson-type polyoxometalates-directed metal-organic complexes with different structures: {H[K(HO)][Cu(pzca)(HO)](TeMoO)} ( 1) and {H[Cu(pzca)(HO)][AlMo(OH)O]}·17HO ( 2) (Hpzca = 2-pyrazine carboxylic acid) have been synthesized and structurally characterized by single crystal X-ray diffraction analyses, thermogravimetric analyses, IR spectra and powder X-ray diffraction analyses. Compound 1 is a 0D architecture, in which the A-type Anderson anion [TeMoO] (TeMo) is modified by two [Cu(pzca)(HO)] cations and two [K(HO)] cations. The adjacent {[K(HO)][Cu(pzca)(HO)](TeMoO)} clusters are connected by hydrogen-bonding interactions, resulting in a 3D supramolecular framework. When B-type Anderson anion [AlMo(OH)O] (AlMo) was used in compound 2, a 2D wave-like network was obtained, in which the adjacent 1D [Cu(pzca)] chains are linked by AlMo anions with two terminal oxygen atoms. The types of Anderson anions play an important role in tuning the structures of the title compounds. In addition, the electrocatalytic activities of title compounds and photocatalytic activities of compound 1 have been studied. [ABSTRACT FROM AUTHOR]

Three new polyoxometalates (POMs)-based hybrid compounds: H[Cu(CHN)(MoO)(HO)]·2(CHN)·2HO ( 1), H[Co(CHN)(MoO)(HO)]·2(CHN)·2HO ( 2) and H[(CHN){Ni(OH)MoO}]·4HO ( 3) (CHN = 3-aminopyridine), have been synthesized by self-assembly of (NH)MoO·4HO, CHN and different metal nitrates at different pH values. The single crystal X-ray diffraction, IR spectra, PXRD and thermogravimetric analyses have been used to characterize the title compounds. Compounds 1 and 2 are isostructural 3D metal-organic frameworks with a CdSO-type topology, which are constructed from infinite MoO inorganic chains in uncommon ABAB linking mode. Compound 3 exhibits a 1D supramolecular chain derived from in situ formed Anderson-type [Ni(OH)MoO] anions and 3-aminopyridine via hydrogen-bonding interactions. The structural diversities indicate that metal ions show great effect on the construction of different POMs and final architectures. The electrochemical behavior of compound 1, the photocatalytic activities of compounds 1- 3 have been investigated in detail. [ABSTRACT FROM AUTHOR]

Two new 3D transition metal coordination polymers [Zn(1,3-BDC)(L)] ( 1) and [Cu(5-AIP)(L)] ( 2) [L = N, N′-di(3-pyridyl)succinamide, 1,3-HBDC = 1,3-benzenedicarboxylic acid, 5-HAIP = 5-aminoisophthalic acid] have been hydrothermally synthesized and structurally characterized by elemental analyses, IR, TG and single crystal X-ray diffraction analysis. In complex 1, two carboxyl groups with monodentate modes from two 1,3-BDC ligands connect two Zn(II) ions to form a dinuclear {Zn} SBUs, then the adjacent {Zn} SBUs are connected by two pairs of 1,3-BDC ligands and two L ligands to construct a 3D coordination network with the large square-shape grids. Finally, the complex 1 exhibits a 4-connected CdSO topology with the threefold interpenetrating feature. Complex 2 is a 3D coordination framework constructed by the ligands L and 5-AIP anions, which represents a binodal (3,8)-connected {4·6}{4·6·7·8} topology. The different coordination modes of metal ions and two dicarboxylates play important roles in the formation of coordination frameworks for title complexes. In addition, the thermal stabilities, the fluorescent properties of complexes 1- 2 and the electrochemical behavior of complex 2 modified carbon paste electrode have also been investigated. Graphical Abstract: Two new 3D coordination polymers, [Zn(1,3-BDC)(L)] ( 1) and [Cu(5-AIP)(L)] ( 2), have been hydrothermally synthesized. Complex 1 represents a threefold interpenetrating CdSO topology, complex 2 exhibits a binodal (3,8)-connected {4·6}{4·6·7·8} topology. The different coordination modes of metal ions and dicarboxylates play important roles in the formation of final structures for title complexes.[Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

Three new copper(II) complexes based on the flexible N, N'-bis(4-pyridinecarboxamide)-1,4-butane (4-dpyb) and three different aromatic dicarboxylic acids [5-methylisophthalic acid (5-HMIP), 5-aminoisophthalic acid (5-HAIP), pyridine-2,6-dicarboxylic acid (2,6-HPDA)], [Cu(4-dpyb)(5-MIP)(HO)]·HO ( 1), [Cu(4-dpyb)(5-HAIP)] ( 2), [Cu(4-dpyb)(2,6-PDA)]·HO ( 3), have been hydrothermally synthesized. X-ray diffraction analysis reveals that complex 1 is a 2 D grid polymeric layer constructed by the [Cu-4-dpyb ] chains and [Cu-5-MIP] chains, and the adjacent layers are further linked by hydrogen bonding interactions to form a 3 D supramolecular structure. Complex 2 is a 3 D supramolecular network based on the polymer chain [Cu(5-HAIP)], in which the discrete 4-dpyb ligands are dispersed. Complex 3 represents a polymer chain based on the μ-bridging 4-dpyb ligand, in which 2,6-PDA only serves as a terminal chelating ligand. For complex 3, the neighboring chains are extended into a 3 D supramolecular structure by hydrogen bonding and π- π stacking interactions. In these complexes, the flexible bis-pyridyl-bis-amide ligands 4-dpyb show the μ-bridging mode (for 1), non-coordinated mode (for 2) and μ-bridging mode (for 3), respectively, and three kinds of aromatic dicarboxylate anions (5-MIP, 5-HAIP and 2,6-PDA) also adopt three different coordination modes. The different coordination modes of ligands 4-dpyb and three dicarboxylates play important roles in the construction of final structures for title complexes. In addition, the thermal stabilities and fluorescent properties of complexes 1- 3 have also been investigated. Graphical Abstract: Three new 3 D supramolecular complexes based on 2 D polymer layers or 1 D chains, [Cu(4-dpyb)(5-MIP)(HO)]·HO ( 1), [Cu(4-dpyb)(5-HAIP)] ( 2), [Cu(4-dpyb)(2,6-PDA)]·HO ( 3), have been hydrothermally synthesized. The different coordination modes of ligands 4-dpyb and three dicarboxylates play important roles in the construction of final structures for title complexes. [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

Two Cu(II) coordination polymers [Cu(4-bpye)(BTC)(HO)]·2HO ( 1) and [Cu(4-bpye)(SIP)(OH)(HO)]·3HO ( 2) [4-bpye = N,N′-bis(4-pyridinecarboxamide)-1,2-ethane, HBTC = 1,3,5-benzenetricarboxylic acid, HSIP = 5-sulfoisophthalic acid], have been hydrothermally synthesized. X-ray diffraction analysis reveals that complex 1 has a fivefold interpenetrating 3D coordination network structure based on 2D double layers, with a trinodal (2,3,3)-connected {10}{6 .10}{6.10} topology. Complex 2 has a 1D ribbon-like chain based on tetranuclear copper clusters, 4-bpye ligands and SIP anions, such that adjacent chains are further linked by hydrogen bonding interactions to form a 3D supramolecular framework. The coordination modes of the tricarboxylate and 4-bpye ligands play important roles in the construction of the two complexes with different dimensionalities. The electrochemical behaviors of both complexes have been studied. [ABSTRACT FROM AUTHOR]

The aim of this study was to explore the influence of the position and angles of carboxyl groups of polycarboxylates on constructing coordination polymers. Three Co(II) metal-organic coordination polymers based on a tri-pyridyl-bis-amide ligand, namely [Co(L)(1,2-BDC)(HO)]·2HO ( 1), [Co(L)(1,4-BDC)(HO)]·2HO ( 2) and [Co (L)(BTEC)]·HO ( 3) (L = N, N′-bis(pyridine-3-yl)pyridine-2,6-dicarboxamide, 1,2-HBDC = 1,2-benzenedicarboxylic acid, 1,4-HBDC = 1,4-benzenedicarboxylic acid, HBTEC = 1,2,4,5-benzenetetracarboxylic acid), have been obtained by tuning the auxiliary polycarboxylate ligands. Structural analyses reveal that complexes 1- 3 display diverse structures. Complex 1 displays a meso-helical chain linked by L ligands, which is further extended into a three-dimensional supramolecular framework through hydrogen-bonding interactions. The 1,2-BDC with a chelating coordination mode only acts as the hydrogen bond acceptor. In complex 2, the 1,4-BDC anions connect adjacent Co(II) atoms to form a linear chain, which is connected by hydrogen-bonding interactions to construct a 3D supramolecular network. Complex 3 exhibits a chain, which is composed of left-/right-handed Co-L helical chains and Co-BTEC linear chain. The 1D chains are ultimately extended into a two-dimensional supramolecular network by hydrogen-bonding interactions. Moreover, the thermal stability and the fluorescent properties of the title complexes and the electrochemical behaviors of a bulk-modified carbon paste electrode with complex 2 have been investigated at room temperature. [ABSTRACT FROM AUTHOR]

Two new Co(II) coordination polymers, [Co(L)(glu)] ( 1) and [Co(L)(npht)]·HO ( 2) (Hglu = glutaric acid, Hnpht = 3-nitrophthalic acid, L = 1,4-bis(5,6-dimethylbenzimidazol-1-ylmethyl)benzene), have been hydrothermally synthesized by self-assembly of cobalt chloride with a semi-rigid bis(benzimidazole) derivative and different organic bicarboxylic acids. Single crystal X-ray diffraction analysis reveals that complex 1 is a one-dimensional tube-like coordination polymer containing one helical [Co-L] and two linear [Co-glu] chains. In complex 2, two npht ligands connect two Co(II) atoms to form a binuclear [Co(npht)] subunit, which is further linked by L ligands with two kinds of conformations to form a 3-D CdSO-like framework. In addition, the electrochemical behaviors of the title complexes in bulk-modified carbon paste electrodes, and their thermal stabilities and fluorescent properties were investigated in this paper. [ABSTRACT FROM AUTHOR]

Two new 3-D supramolecular complexes [M(4-bpcb)(bbtc)(HO)]·3HO [M = Co ( 1), Ni ( 2), 4-bpcb = N,N′-bis(4-pyridinecarboxamide)-1,4-benzene, bbtc = 3,3′,4,4′-benzophenonetetracarboxylate] have been hydrothermally synthesized by self-assembly of 3,3′,4,4′-benzophenonetetracarboxylic acid dianhydride (bbtcd) and bis-pyridyl-bis-amide 4-bpcb mixed ligands. X-ray diffraction analysis reveals that two-dimensional (2-D) coordination networks of complexes 1 and 2 are constructed from neutral {M(bbtc)(HO)} [M = Co ( 1), Ni ( 2)] ribbon-like chains and ligand 4-bpcb with bidentate coordination mode. The adjacent layers for 1 and 2 are further linked by hydrogen bonding interactions to form 3-D supramolecular frameworks. Moreover, the thermal properties and the electrochemical properties of the two title complexes have been reported. Graphical Abstract: Two new three-dimensional supramolecular complexes based on two-dimensional polymer layer, [M(4-bpcb)(bbtc)(HO)]·3HO [M = Co ( 1), Ni ( 2)], have been synthesized from hydrothermal reaction of metal(II) chloride with the mixed ligands 3,3′,4,4′-benzophenonetetracarboxylic acid dianhydride (bbtcd) and bis-pyridyl-bis-amide ligand N, N′-bis(4-pyridinecarboxamide)-1,4-benzene (4-bpcb).[Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

Two new 2D metal-organic complexes, namely [Cu(3-dpyb)(1,2,4-HBTC)(HO)]·HO ( 1) and [Cu(3-dpyb)(SIP)(HO)]·6HO ( 2) [3-dpyb = N,N'-bis(3-pyridinecarboxamide)-1,4-butane, 1,2,4-HBTC = 1,2,4-benzenetricarboxylic acid, HSIP = 5-sulfoisophthalic acid], have been hydrothermally synthesized and structurally characterized by elemental analyses, IR, TG, and single crystal X-ray diffraction analyses. Single crystal X-ray analyses reveal that the two Cu(II) complexes show different 2D coordination networks, the 4-connected (4·6) topology for complex 1 and the (4·6)(4·6·8) topology for complex 2. In the 2D layers of complexes 1 and 2, the 3-dpyb ligands adopt a typical μ-bridging mode (via ligation of two pyridyl nitrogen atoms ), while 1,2,4-HBTC and SIP serve as a linear spacer and a 'V'-like linker, respectively, to connect the adjacent Cu(II) centers. The adjacent 2D layers are extended to 3D supramolecular networks via hydrogen-bonding interactions. The fluorescence properties of both complexes and electrochemical properties of complex 2 have also been investigated. The complex 2 bulk-modified carbon paste electrode ( 2-CPE) displayed a one-electron redox wave in potential range of 600-200 mV in 1 M HSO aqueous solution, and 2-CPE showed good electrocatalytic activity toward the reduction of nitrite. [ABSTRACT FROM AUTHOR]

A new POM-templated metal-organic complex [Cu(L)(HO)(SiMoO)]·7HO [L = N, N′-bis(3-pyridinecarboxamide)-1,6-hexane], has been hydrothermally synthesized and characterized by elemental analysis, IR, TG and single-crystal X-ray diffraction analysis. The results reveal that the complex is a 2D metal-organic coordination framework of [Cu(L)(HO)] cations containing decanuclear cycles with dimensions of ca. 17.55 × 57.42 Å, in which the SiMoO anions act as non-coordinated anionic templates. The electrochemical properties of a bulk-modified carbon paste electrode of the complex have been investigated, and the results indicate that the complex-modified CPE has good electrocatalytic activity toward the reduction of nitrite in aqueous 1 M HSO solution. [ABSTRACT FROM AUTHOR]

Three new Co coordination polymers, namely [Co(DNBA)(pbdmbm)] ( 1), [Co(HO)(DNBA)(ebdmbm)] ( 2) and [Co(DNBA)(pbbm)] ( 3) have been obtained by hydrothermal reactions of Co with flexible bis(benzimidazole) ligands [1,1′-(1,3-propanediyl)bis(5,6-dimethylbenzimidazole) (pbdmbm), 1,1′-(1,2-ethanediyl)bis(5,6-dimethylbenzimidazole) (ebdmbm), 1,1′-(1,3-propanediyl)bis(benzimidazole) (pbbm)] plus 3,5-dinitrobenzoic acid (HDNBA). The complexes have been characterized by single crystal X-ray diffraction, elemental analyses, IR and TG. Complexes 1 and 3 exhibit one-dimensional chains composed of Co centers bridged by flexible bis(benzimidazole) ligands. Complex 2 is a three-dimensional NaCl-type supramolecular framework constructed from binuclear units, which are formed by two Co centers and two ebdmbm ligands. The spacer length and substituents on the bis(benzimidazole) ligands are crucial for the construction of these structures. The photoluminescence properties of the complexes and the cyclic voltammetry behavior of complex 1 are described. [ABSTRACT FROM AUTHOR]

Three new polymeric frameworks, [Ni(bbbm)(L1)] ( 1), [Ni(bbbm)(L2)] ( 2), and {[Co(bbbm)(L3)]·HO} ( 3) (bbbm = 1,4-bis( N-benzimidazolyl) butane, HL1 = 4-bromobenzoic acid, HL2 = 3-methylbenzoic acid, and HL3 = glutaric acid) have been hydrothermally synthesized and structurally characterized by single-crystal X-ray diffraction. Complex 1 features a one-dimensional (1D) linear chain structure bridged by bbbm ligands, which is further connected into a supramolecular double chain structure through intermolecular π-π stacking interactions. Complex 2 contains 1D zigzag chain, which is further arranged into a 2D supramolecular architecture by hydrogen bonding and π-π stacking interactions. In the structure of 3, there are infinite 1D zigzag Co(II)-bbbm chains linked together by L3 ligands to generate an undulated 2D (4,4) sheet, which is further connected by intermolecular π-π stacking interactions to form a 3D supramolecular network. Furthermore, thermal stability and luminescent property of 1- 3 were investigated. Graphical Abstract: Three new two/three-dimensional supramolecular complexes [Ni(bbbm)(L1)] ( 1), [Ni(bbbm)(L2)] ( 2), and {[Co(bbbm)(L3)]·HO} ( 3) [bbbm = 1,4-bis( N-benzimidazolyl) butane] have been synthesized from hydrothermal reaction of a metal salt with ligands: bbbm and one carboxylate ligand, 4-bromobenzoic acid (HL1), 3-methylbenzoic (HL2), and glutaric acid (HL3).[Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

new Keggin-type polyoxometalate-based compound {[Cu( L)(HO)](PWWO)}·16HO ( 1) constructed from PWWO, N,N′-bis(4-pyridylformyl) piperazine ( L) and Cu(II) has been hydrothermally synthesized and structurally characterized by elemental analyses, IR and single-crystal X-ray diffraction analysis. Single-crystal X-ray diffraction analysis reveals that the semi-rigid piperazine-based ligands L coordinate to the Cu(II) atoms to constitute a two dimensional coordination network. The 2D (4, 4) cationic layers are stacked together in a perpendicular mode, resulting in the formation of twofold interpenetrating frameworks with large cavities. The PW anions reside in the large cubic-like cavities, serving as non-coordinating templates. The compound 1 displays good electrocatalytic activity toward the reduction of nitrite in 1 M HSO aqueous solution. [ABSTRACT FROM AUTHOR]