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The strain Achromobacter insolitus LCu2 isolated from the roots of alfalfa (Medicagosativa L.) utilized cinnamic acid and its methoxy derivatives (vanillic and ferulic acids) as the sole carbon source. Weak growth was observed with m-coumaric acid, but not on o- or p-coumaric acids. Growth on the cinnamic acid was slow and diauxic. The substrate decreased in the cultivation medium by 53%; the degradation efficiency during 14 days was 30 μg/mg wet weight. Despite the bactericidal effect of cinnamic acid, the culture A. insolitus LCu2 remained viable for a long time. Genomic analysis revealed two gene clusters (hca and mhp) responsible for the dihydroxylation of the phenyl ring (hcaA1A2CDB) and its subsequent cleavage to central metabolic products (mhpACDE), as well as a transcriptional regulator (hcaR) and a putative transporter (hcaT). A putative biochemical pathway for cinnamic acid degradation by the strain A. insolitus LCu2 was predicted using genomic data. [ABSTRACT FROM AUTHOR]

A mononuclear complex [Zn(phbz)2(phen)] (1, Hphbz = 4-biphenylcarboxylic acid, phen is 1,10-phenanthroline) is obtained, and its structure is determined by single crystal X-ray diffraction (XRD). It is additionally characterized by powder XRD, IR and NMR spectroscopy. The theoretic simulation (DFT B3LYP/Def2-TZVP) of the dimerization process of the complex shows that one of the reasons for the lack of experimental detection of dimeric structures of this type may be a low stabilization energy of the hypothetical binuclear compound [Zn2(phbz)4(phen)2]. [ABSTRACT FROM AUTHOR]

Manganese(II) and cobalt(III) complexes [Mn(HL)Cl2] (1) and [Co(L)2]Cl (2) with 2-amino-N'-(pyridin-2-ylmethylene)benzhydrazide (HL) were synthesized. Complexes 1 and 2 contain a neutral acylhydrazone molecule (1) or two acylhydrazones in the anionic form (2) in the coordination sphere of the metal centers. In vitro antibacterial and antifungal activities of acylhydrazone HL and coordination compound 2 were assessed. [ABSTRACT FROM AUTHOR]

Barium–copper(II) and barium–iron(III) coordination polymers with malonic acid dianions [BaCuII(Mal)2(H2O)4]n (1) (CCDC No. 2239603) and (2) (CCDC No. 2239902) are prepared for the first time. The complexes are built by bischelate fragments of 3d metals {M(Mal)2}x– (x = 2 for 1, x = 1 for 2) forming layers (1) or fragments coupled by OH bridges (2) in the crystal. The barium atoms coordinate O atoms of chelate-bridging malonate anions and bridging water molecules that are additionally H-bonded to the {M(Mal)2}x– fragments in 1 and 2, thus forming complex Ba–O–H...{M(Mal)2} bridges suitable for the formation of 3D and 2D polymers, respectively. The new compounds are characterized by single-crystal XRD, IR spectroscopy, CHN analysis, and powder XRD methods. [ABSTRACT FROM AUTHOR]

Strontium(II)—zinc(II) and strontium(II)—cadmium(II) coordination compounds with dianions of cyclobutane-1,1-dicarboxylic acid (H2cbdc) were synthesized. In the complexes [Sr4Zn4(cbdc)8(H2O)9]n(1) and {[SrCd(cbdc)2(H2O)3] · 3H2O}n(2), the cyclobutane-1,1-dicarboxylate dianions are coordinated to strontium atoms in a chelate fashion to form monomeric mono- and bischelate moieties, which link the d-metal atoms into a polymer structure. An increase in the ion radius of the d-metal in going from zinc(II) to cadmium(II) is accompanied by a decrease in the dimensionality of the coordination polymer from layered to chain. [ABSTRACT FROM AUTHOR]

The results of studying heterometallic complexes Ln(III)–Cd(II) with anions of aromatic and aliphatic monocarboxylic acids are generalized. A number of substantial features is observed in complexes Ln(III)–Cd(II), but they are not characteristic of compounds Ln(III)–М(II) with 3d-metal ions (M = Co, Ni, Cu, Zn). A tendency of the cadmium(II) complexes to form coordination polymers at the compositions typical of the molecular 3d-metal complexes is shown. The effect of the substituent in benzoic acid on the structures and photoluminescence properties of the heterometallic Ln(III)–Cd(II) complexes is revealed. [ABSTRACT FROM AUTHOR]

Methods for the synthesis were developed and new homo- and heterometallic cadmium ([Eu2Cd2(MeCN)4(C6F5COO)10] (I), [Tb2Cd2(MeCN)6(C6F5COO)10]·4MeCN (II)) and zinc ([Zn(H2O)(C6F5COO)2] (III), [Eu2Zn2(MeCN)4(C6F5COO)10] (IV)) complexes were characterized. These complexes can be used as precursors for the synthesis of compounds with N-donor ligands. Complexes I and II differ in the coordination of the MeCN molecule, which is coordinated in II by each Tb3+ ion. Also, additional coordination of MeCN induces a greater distortion of the {Tb2Cd2} metal core of II. The crystal packing in I–IV is stabilized by numerous intermolecular O...H, F...F, C–H...F, and C–H...O contacts. The new compounds were characterized by single crystal X-ray diffraction (CCDC no. 2076524 (I), 2082731 (II), 2082803 (III), 2076525 (IV)), IR spectroscopy, C,H,N elemental analysis, and powder X-ray diffraction. [ABSTRACT FROM AUTHOR]

The required amount of abscisic acid containing 4 – 5 D atoms ([2H]ABA) in the cyclohexene fragment of the molecule was produced via isotope exchange in 100% deuterated D2O at 220°C in the presence of diisopropyl ethylamine. The yield of labeled compound was 45 – 80%. A complex of biological studies was carried out using the D-labeled preparation. It was established that [2H]ABAserved as a growth substrate for soil bacteria, which included the isotopic label in the composition of cell metabolites. The characteristics of D-labeled metabolites allowed their reliable identification in mass spectra of the total bacterial metabolome. Three intermediates of a new metabolic pathway of microbial degradation of this phytohormone were identified using the developed technique. [ABSTRACT FROM AUTHOR]

The effect of bulky tridentate ligands on the geometry of carboxylate complexes was studied in relation to hexahydro-1,3,5-trimethyl-1,3,5-triazine (TACH). The reaction of [Co2Gd(NO3)(Piv)6(MeCN)2] (Piv is the pivalic acid anion) with TACH gave the complex [Co2Gd(NO3)(Piv)6(TACH)2] (I), in which the initial heterometallic moiety was retained and cobalt(II) ions coordinated the N-donor ligand to give a half-sandwich structure. The use of Cd(II) and Eu(III) pentafluorobenzoates in the reaction with TACH resulted in the isolation of only the homometallic complex [Cd(Pfb)2(TACH)2] (II) (Pfb is pentafluorobenzoic acid anion). Owing to high coordination number of cadmium(II) ion in II, a sandwich complex with two TACH molecules coordinated to the same metal ion was obtained. The structure of new complexes was determined by X-ray diffraction (CIF file CCDC nos. 2062230 (I) and 2062229 (II)). It was shown that binding of an N-donor ligand to a metal ion induces a significant distortion of the metal coordination polyhedra and a conformational change of hexahydro-1,3,5-trimethyl-1,3,5-triazine. [ABSTRACT FROM AUTHOR]

Heteroleptic cadmium(ii) carboxylates with anions of pentafluorobenzoic (pfb), benzoic (bz), and 2-furancarboxylic (fur) acids were prepared by the crystallization from aqueous solutions. The cadmium(ii) pentafluorobenzoate-benzoate complex is structurally similar to the starting compound [Cd(pfb)(H2O)4]n • n(pfb): bz anions are involved in the cationic 1D polymer {[Cd(bz)(H2O)3]n}n+, whereas pfb anions are outer-sphere. The pentafluorobenzoate-2-furan-carboxylate compound [Cd(fur)(pfb)(H2O)2]n•n(H2O) is a 1D coordination polymer. The heteroleptic TbIII complex [Tb2(bz)2(pfb)4(H2O)2(EtOH)2]•2Hbz has a molecular structure. The supramolecular crystal structures of the new compounds are stabilized by non-covalent interactions. [ABSTRACT FROM AUTHOR]

The binuclear cadmium complexes in which the metal atoms are linked by two chelate-bridging carboxylate anions, [Cd2L2(µ2-(Рiv)2(κO,κO'-(Рiv)2] (L is 2,4-lutidine, phenanthridine, and 2,2'-bipyridine; and Рiv is pivalate anion), and the complexes with the "Chinese lantern" structure in which the cadmium atoms are linked by four bridging carboxylate anions, [Cd2L2(µ2-(Рiv)4] (L is 2,3-cyclododecenopyridine (Сdpy)) and [Cd2(L)2(µ2-(PfAc))4] (L is 1,10-phenanthroline, and PfAc is pentafluorophenylacetate anion), are considered. The two-bridge and four-bridge isomers of each binuclear [Cd2L2(Рiv)4] complex with the monodentate and chelating N-donor ligands are calculated by the density functional theory using four different approximations. The stabilities of the isomers are compared and conclusions about the factors leading to the formation of complexes of this or another structure are made on the basis of the calculation data. [ABSTRACT FROM AUTHOR]

A series of the cadmium and zinc carboxylate complexes with anions of pentafluorobenzoic (HРfbz) and 2,3,4,5-tetrafluorobenzoic (HТfbz) acids and N-donor ligands (1,10-phenanthroline (Phen) and quinoline (Quin)), [Cd(Pfbz)2(Phen)]n (I), [Cd(Рfbz)2(Рhen)2]·2MeCN (II), [Zn(H2O)-(Рfbz)2(Рhen)] (III), [Zn2Cd(Рfbz)6(Рhen)2]⋅2C6H6 (IV), [Cd2(H2O)2(Tfbz)4(Рhen)2] (V), [Cd2-(H2O)2(Tfbz)4(Quin)2] (VI), and [Cd(Tfbz)2(Phen)2]⋅HTfbz (VII), is synthesized. The structures of new complexes I–VII are determined by X-ray diffraction analysis (CIF files CCDC nos. 1871300, 2005461, 2005462, 2005464, 2005466, 2005465, and 2005459, respectively). The majority of the synthesized compounds is typical of intramolecular stacking interactions between the coordinated molecules of the aromatic N-donor ligands and fluorinated substituents of the carboxylate anions. These interactions lead to the formation of unusual compounds, which are different in the cases of pentafluorobenzoates and tetrafluorobenzoates, in particular, coordination polymer I and binuclear complexes V and VI with coordinated water molecules. The synthesized zinc and cadmium compounds differ in structure and composition. [ABSTRACT FROM AUTHOR]

The reactions of cadmium(II) and europium(III) pentafluorobenzoates ([Cd(Pfbz) }n ∙ n(Pfbz)–] (I) and [Eu2(Pfbz)6(H2O)8] ∙ 2H2O (II), respectively; Pfbz is pentafluorobenzoic acid anion) with the N-donor ligands (pyridine (Py), 2-phenylpyridine (Phpy), and 3-ethynylpyridine (Etypy)) afford a series of new Cd–Ln complexes with Pfbz– anions and Py or its substituted analogues: [Cd2Eu2(Pfbz)10(Py)4] (III), [Cd2Eu2(Pfbz)10(Phpy)2(MeCN)2] · 5MeCN (IV), and [CdEu2(Pfbz)8(Etypy)(H2O)2]n ∙ 3nMeCN ∙ n(Etypy) (VI). Similar reactions of compounds I and II with 2,4-lutidine (Lut), isoquinoline (Iquin), 2,2'-biquinoline (Biquin), and 7,8-benzoquinoline (Bquin) give the following cadmium complexes as the major products of crystallization from the reaction solutions: [Cd(Pfbz)2(Lut)]n (V), [Cd(H2O)(Pfbz)2(Iquin)2]n (VII), [Cd(Рfbz)2(Biquin)] (VIII), and ∙ n(HBquin)+ (IX), respectively. The X-ray diffraction data (CIF files CCDC nos. 1987805 (I), 1987808 (III), 1987829 (IV), 1987817 (V), 1987822 (VI), 1987823 (VII), 1987824 (VIII), and 1987826 (IX)) are examples of the formation of new unusual coordination polymers. [ABSTRACT FROM AUTHOR]

A new unusual molecular complex [Cd6(CO3)(Piv)10(Phen)2] (I) was prepared by the reaction of cadmium(II) trimethylacetate, Cd(Piv)2 · 2H2O, and 1,10-phenanthroline (Phen) in 2 : 1 ratio in acetonitrile in air. Six cadmium atoms form a trigonal prismatic metal core and are connected to the carbonate anion located inside it. The structure of complex I was derived from X-ray diffraction data (CIF file CCDC no. 1912223). [ABSTRACT FROM AUTHOR]

The reaction of Cd(NO3)2 · 4H2O and Eu(NO3)3 · 6H2O or Tb(NO3)3 · 6H2O with potassium 3,5-di-tert-butylbenzoate (Kbzo) and N-donor ligands (1,10-phenanthroline (phen), 2,4-lutidine (2,4-lut), 3,4-lutidine (3,4-lut), phenanthridine (phtd), 2,3-cyclododecenopyridine (cdpy), acridine (acr)) afforded heterometallic LnCd2 complexes: [EuCd2(bzo)7(EtOH)2(phen)] (2), [LnCd2(bzo)7(2,4-lut)4] (Ln = Eu (3), Tb (4)), [EuCd2(bzo)7(H2O)2(2,4-lut)2] · MeCN (5), [EuCd2(NO3)(bzo)6(EtOH)2(2,4-lut)2] (6), [EuCd2(bzo)7(H2O)(EtOH)(3,4-lut)2] · 5EtOH (7), 3[EuCd2(bzo)7(H2O)2(phtd)2] · 4phtd (8), [EuCd2(bzo)7(EtOH)3(cdpy)] (9), 2[EuCd2-(bzo)2(EtOH)4] · acr (10). The structures of complexes 2, 3, and 5–10 were determined by single-crystal X-ray diffraction. The isostructurality of complexes 3 and 4 was confirmed by powder X-ray diffraction. The structure of the trinuclear {Ln2Cd} metal core is stable and independent of the type of peripheral ligands coordinated to cadmium atoms. Photoluminescent properties of compounds 3 and 4 were studied. [ABSTRACT FROM AUTHOR]

The reactions of Cd(NO3)2 ∙ 4H2O and Eu(NO3)3 ∙ 6H2O with potassium salts of the benzoic acid derivatives and 2,2'-bipyridine (Bipy) in ethanol, under the same synthesis conditions, afford the homo- and heterometallic complexes: [Eu2Cd2(BA)8(NO3)2(Bipy)2] (I, BA is benzoic acid anion), [Ln2Cd2(4-TBA)10(Bipy)2] (Ln = Eu (II), Tb (III); 4-TBA is 4-(trifluoromethyl)benzoic acid anion), [Cd(4-CBA)2(H2O)(Bipy)] (IV, 4-CBA is 4-cyanobenzoic acid anion), [Cd(PFBA)2(H2O)(Bipy)]n (V, PFBA is pentafluorobenzoic acid anion), and [Cd2(4-APFBA)4(Bipy)2] ∙ 4H2O (VI, 4-ATFBA is 4-amino-2,3,5,6-tetrafluorobenzoic acid anion). The structures of new complexes I, II, IV, and VI are determined by X-ray structure analysis (CIF files CCDC nos. 1970348, 1970350, 1970347, and 1970351, respectively). The isostructural character of complexes II and III is confirmed by X-ray diffraction analysis. The structures and compositions of the series of isolated compounds I–VI are determined by the nature of substituents in the benzoate anion. The photoluminescence properties of compounds II and III are studied. [ABSTRACT FROM AUTHOR]

A procedure was developed for introducing tritium into the side chain of the abscisic acid (ABA) molecule. The reaction was carried out in dioxane in the presence of the Lindlar catalyst. The yield of the labeled product was 70% and the molar radioactivity was 44 Ci/mol. The tritium-labeled abscisic acid analogue was found to be a growth substrate for soil bacteria that incorporate a radioactive label into cellular metabolites. The absorption of the label by bacteria from the side chain of abscisic acid is more than an order of magnitude higher than that for labeling in the cyclohexene moiety. The results indicate the existence of a previously unknown metabolism pathway of ABA in microorganisms. [ABSTRACT FROM AUTHOR]

Data on the synthesis and study of the crystal structure of [Li10(Piv)10(MeCN)2]n (I) and [Li6(Piv)6(MeCN)2]n (II) are presented. According to X-ray diffraction data (CIF files CCDC nos. 1957855 (I); 1955569 (II)), compounds I and II are 1D polymers composed of deca- and hexanuclear fragments, respectively, in which the lithium atoms are linked to one another by μ3- and μ4-bridging pivalate anions. [ABSTRACT FROM AUTHOR]

New trinuclear Cd–Ln molecular complexes [EuCd2(O2CC6F5)6(NO3)(Bipy)2] (I, Bipy is 2,2'-bipyridine) and [LnCd2(Bzo)6(NO3)(Phen)2] · 4MeCN (Ln = Tb (II), Eu (III), Bzo is anion of 3,5-di-tert-butylbenzoic acid, Phen is 1,10-phenanthroline) are studied. Their structures are determined by X-ray structure analysis (СIF files CCDC nos. 1938125 (I), 1938124 (II)) or by X-ray diffraction analysis (III), and the photoluminescence properties are studied. The reactions of complexes I and II with terephthalic acid (H2Bdc) are accompanied by the destruction of the heterometallic molecules to form 2D coordination polymers [Cd3(Bbdc)3(Bipy)2]3n · 4nMeCN · nH2O (IV) and [Cd2(Bdc)2(Phen)2]n · 2nDMF (V) (СIF files CCDC nos. 1938126 and 1937492, respectively). [ABSTRACT FROM AUTHOR]

Phosphorescence of liquid oxygen under excitation at cooperative transitions of О2–О2 molecular oxygen complexes is studied using direct optical excitation by LED arrays emitting in the near-UV and visible spectral regions at wavelengths partially or completely coinciding with the absorption lines of the molecular complexes. [ABSTRACT FROM AUTHOR]

The review summarizes the data obtained in the studies of transition metal complexes (VIVO, CoII, NiII, CuII, ZnII) with anions of substituted malonic acids, which are not only coordination polymers but also compounds with a discrete molecular structure. The influence of malonic acid substituents and the nature of metal ions (alkali, alkaline earth, and transition metals) on the formation of molecular and polymeric systems is discussed. The crystal structures of recently described heterometallic coordination polymers are analyzed. [ABSTRACT FROM AUTHOR]

Abstract: A procedure for tritiation of predominantly the cyclohexene moiety of abscisic acid was developed. Tritium was introduced by isotope exchange reaction with 100% tritiated water at 220°C in the presence of diisopropylethylamine. The yield of abscisic acid was 50%, and the specific activity was 30.5 Ci/mmol. The labeled product was tested. It was shown that tritiated abscisic acid synthesized by the proposed method did not differ from the unlabeled precursor and could be used for biological assays. [ABSTRACT FROM AUTHOR]

Abstract: The recrystallization of complex [Ni9(OH)6(Piv)12(HPiv)4] (Piv- is anion of trimethylacetic acid) from a THF-MeCN (6 : 1) mixture gives a new hexanuclear compound of nickel(II): [Ni6(µ3-OH)2(Piv)10(THF)4]. Its structure (CIF file CCDC no. 1579976) exhibits rare examples of coordination of the µ2-THF and µ4-Piv ligands. [ABSTRACT FROM AUTHOR]

Abstract: The exchange reaction of CdCl2 ⋅ 2H2O with KPiv affords cadmium(II) trimethyl acetate complexes (K[Cd6(Piv)12Cl] ⋅ 2MeCN (I), [K2Cd3(Piv)8(H2O)6] (II), and [Cd(Piv)2(Н2О)2] (III) as a mixture with complex II and [K3Cd2(Piv)7(MeCN)2]n (IV) (HPiv is trimethylacetic acid). The exchange reaction of CdSO4 ⋅ 8/3H2O with Ba(Piv)2 makes it possible to obtain complex III in a quantitative yield. Complex III can also be isolated by the recrystallization of {Cd(Piv)2} from water. The recrystallization of complex III or {Cd(Piv)2} from MeCN affords hexanuclear complex [Cd6(Piv)12(MeCN)2] (V), which transforms into complex III upon recrystallization from water. All new compounds are characterized by the data of single-crystal X-ray diffraction analysis (CIF files CCDC no. 1572202-1572206), IR spectroscopy, and C,H,N analysis. [ABSTRACT FROM AUTHOR]

Prokaryotic diversity was studied in the planktonic communities of six Sol-Iletsk lakes (Orenburg oblast, Russia) varying in salinity level using the Illumina technology of high-throughput sequencing. The extremely halophilic archaea of the phyla Euryarchaeota and Nanohaloarchaeota, as well as the bacterial phylum Bacteroidetes predominated in the communities of lakes with salinity of 285-300‰. Representatives of the phyla Bacteroidetes and Actinobacteria, as well as of the class Gammaproteobacteria were predominant in the lakes with salinity 110−180‰. A bloom of Cyanobacteria was observed in Bol’shoe Gorodskoe Lake (10‰ salinity). The dominant OTUs in the lakes with high salinity were represented by archaea Halonotius sp., uncultured Nanohaloarchaea, and bacteria Salinibacter sp. In the lakes with medium salinity level the dominants included gammaproteobacteria Spiribacter sp., alphaproteobacteria Roseovarius sp., flavobacteria Psychroflexus sp., unidentified archaea of the family Haloferacaceae, actinobacteria Pontimonas sp. and Rhodoluna sp. In the lake with low salinity level cyanobacteria of the genus Planktothrix were predominant. Effect of salinity on prokaryotic taxonomic richness, composition, and diversity in planktonic communities of the studied lakes was demonstrated. [ABSTRACT FROM AUTHOR]

Modern techniques of next-generation sequencing (NGS) allow obtaining expression profile of all genes and provide an essential basis for characterizing metabolism in the organism of interest on a broad scale. An important condition for obtaining a demonstrative physiological picture using high throughput sequencing data is the availability of the genome sequence and its sufficient annotation for the target organism. However, a list of species with properly annotated genomes is limited. Transcriptome profiling is often performed in the so-called non-model organisms, which are those with unknown or poorly assembled and/or annotated genome sequences. The transcriptomes of non-model organisms are possible to investigate using algorithms of de novo assembly of the transcripts from sequences obtained as the result of RNA sequencing. A physiological interpretation of the data is difficult in this case because of the absence of annotation of the assembled transcripts and their classification by metabolic pathway and functional category. An algorithm for transcriptome profiling in non-model organisms was developed, and a transcriptome analysis was performed for the basidiomycete Lentinus edodes. The algorithm includes open access software and custom scripts and encompasses a complete analysis pipeline from the selection of cDNA reads to the functional classification of differentially expressed genes and the visualization of the results. Based on this algorithm, a comparative transcriptome analysis of the nonpigmented mycelium and brown mycelial mat was performed in L. edodes. The comparison revealed physiological differences between the two morphogenetic stages, including an induction of cell wall biogenesis, intercellular communication, ion transport, and melanization in the brown mycelial mat. [ABSTRACT FROM AUTHOR]

Morphological and physiological properties, the partial sequence of the 16S rRNA gene, and the ultrastructure of a novel halotolerant hydrocarbon oxidizing bacterium Kocuria sp. (strain ICIS A2.2) isolated from the association with the ciliate Cyclidium sp. have been characterized. Morphological and ultrastructural changes have been revealed in cells of the studied strain while growing in a media with different carbon sources (sucrose or diesel fuel). At the cellular level, the enlargement of the cells, changes in their shape, and the formation of aggregates occur. At the subcellular level, both the number and size of cytoplasmic membrane bodies increase and electron-transparent inclusions appear. These changes may be considered a result of adaptation to a medium containing hydrocarbons. [ABSTRACT FROM AUTHOR]

A series of binuclear tetracarboxylate-linked Mn(II), Fe(II), Co(II), Ni(II), and Cu(II) complexes with 1,2-substituted pyridine, viz., 2,3-cyclododecenopyridine (L), were prepared. Study of the crystal structures of isolated compounds (CIF file CCDC nos. 1575855-1575859) revealed a distortion of the {Ni2(O2CR)4L2} binuclear moiety, manifested as a change in the NiNiN angle (151.67°), in the bridging function of two out of the four carboxylate groups (from μ2- to (κ²,μ2-)), and in the coordination environment of the metal ion (NiO5N). The results were analyzed in comparison with known data. The magnetic properties of copper(II) and nickel(II) complexes were studied. The copper(II) complex is diamagnetic as a result of strong exchange interactions between the unpaired electrons; in the nickel(II) complex antiferromagnetic exchange interactions were detected (JNi-Ni = -25 cm-1). [ABSTRACT FROM AUTHOR]

A series of binuclear tetracarboxylate-linked Mn(II), Fe(II), Co(II), Ni(II), and Cu(II) complexes with 1,2-substituted pyridine, viz., 2,3-cyclododecenopyridine (L), were prepared. Study of the crystal structures of isolated compounds (CIF file CCDC nos. 1575855-1575859) revealed a distortion of the {Ni2(O2CR)4L2} binuclear moiety, manifested as a change in the NiNiN angle (151.67°), in the bridging function of two out of the four carboxylate groups (from μ2- to (κ²,μ2-)), and in the coordination environment of the metal ion (NiO5N). The results were analyzed in comparison with known data. The magnetic properties of copper(II) and nickel(II) complexes were studied. The copper(II) complex is diamagnetic as a result of strong exchange interactions between the unpaired electrons; in the nickel(II) complex antiferromagnetic exchange interactions were detected (JNi-Ni = -25 cm-1). [ABSTRACT FROM AUTHOR]

Data on the synthesis of carboxylate complexes combining transition 3 d metals and diverse heterometals (Li-, Mg-, and Ln-M(3 d)) are reviewed. The factors that are essential to the structure of heterometallic complexes were revealed. Stable metal-containing moieties capable of forming both molecular and polymeric structures were identified. [ABSTRACT FROM AUTHOR]

The reaction products of [Cd(piv)] (piv is-OCBu) with isoquinoline (iqn), 2,4-lutidine (lut), phenanthridine (phend), 2,3-cyclododecenopyridine (cpy), and triethylamine (EtN) were synthesized and their structures were determined. The steric factors were found to play a more important role in cadmium( ii) pivalate complexes compared to 3d metal carboxylates in the +2 oxidation state. The reaction of [Cd(piv)] with isoquinoline produces only the mononuclear complex [Cd(piv)(iqn)] ( 1). The reaction of [Cd(piv)] with pyridine derivatives bearing a bulky substituent at the α position is accompanied by the formation of symmetrical dinuclear complexes of the composition [Cd(piv)(L)]. In the complexes with L = lut ( 2) or phend ( 3), the cadmium( ii) atoms are linked by two chelating-bridging carboxylate groups; in the complex with L = cpy ( 4), by four bidentate-bridging groups. The reaction of [Cd(piv)] with EtN in a solution of MeCN gives the centrosymmetric linear trinuclear complex [Cd(piv)(EtN)] ( 6); in a mixture of benzene and hexane, the ionic compound (HEtN)[Cd(piv)(HO)] ( 7). The crystal structures of all synthesized compounds were determined by X-ray diffraction. [ABSTRACT FROM AUTHOR]

Heterometallic malonate complexes [AgNi(HO)(Rmal)] (Rmal is the dimethylmalonate dianion (Memal) ( 1) or the cyclobutane-1,1-dicarboxylate dianion (Cbdc) ( 2)) and [AgCu(HO)(Memal)] ( 3) were synthesized. The bis-chelate fragment {M(Rmal)} (M = Ni, Cu) composed of two dianions of an acid and a 3d metal atom is the structure-forming unit of these complexes. The mononuclear fragments are linked by silver(I) atoms, which are involved in argentophilic interactions, to form 2D coordination polymers. [ABSTRACT FROM AUTHOR]

Conditions for chemical assembly of new heterometallic trinuclear pivalates [CdM(piv)L] (M = Mg, Ca, or Sr; piv is pivalate) were found. Reactions with the nonchelating ligand 2,4-lutidine (lut) gave the crystals of heterometallic complexes [CdM(piv)(lut)] (M = Mg ( 1), Ca ( 2), and Sr ( 3)). With the chelating ligand 1,10-phenanthroline (phen), only the homometallic dimer [Cd(piv)(phen)] ( 4) was obtained under these conditions. Yet heterometallic trinuclear complexes with 1,10-phenanthroline ([CdMg(piv)(HO)(phen)] ( 5), [CaCd(piv)(phen)] ( 6), and [CdSr(piv)(phen)]∙2MeCN ( 7)) were synthesized by reactions of phen with complexes 1- 3. For all the complexes obtained, the molecular and crystal structures as well as the details of their molecular architecture were determined. The thermal behavior of aqua complex 5 was studied by TG and DSC. The complex eliminated the water molecule between 130 and 180 °C with a high endothermic effect ( Q = 101 kJ mol) due to (1) intramolecular hydrogen bonds that stabilize its molecular architecture and (2) subsequent structural rearrangements. [ABSTRACT FROM AUTHOR]

A reaction of potassium dimethylmalonate (KMeMal) with cobalt(II) or nickel(II) trimethylacetate in the presence of 18-crown-6 leads to the formation of 36-nuclear complexes {[K(18-crown-6)][K(HO)(18-crown-6)][KCo(HO)(OH)(MeMal)(18-crown6)(O)]• xHO} ( 2) and {[K(HO)(18-crown-6)][KNi(HO)(OH)(18-crown-6)(MeMal)(HMeMal)][KNi(HO)(OH)(18-crown-6)(MeMal)(HMeMal)]• •80HO} ( 3) (MeMal is the dianion of dimethylmalonic acid), respectively. The single crystal X-ray diffraction studies showed that the spherical 36-nuclear polyanions [Co(HO)(OH)(MeMal)(O)] (in compound 2) and [Ni(HO)(OH)(MeMal)(HMeMal)] (in compound 3; x = 1, y = 7; x = 2, y = 6) have similar structures, with their metal cores being formed of two layers: an internal one comprising 24 metal atoms and an external containing 12 metal centers. The inner cavity of the {M} anions was found to include one K aqua cation bonded to the oxygen atoms of the carboxylate or oxo ligands. [ABSTRACT FROM AUTHOR]

Structural data for known and newly obtained copper(II) complexes with 2,2′;6′,2″-terpyridine and substituted malonic (dimethylmalonic, 1,1-cyclopropane- and 1,1-cyclobutanedicarboxylic) acid dianions Rmal were used to show that the coordination environment of the metallocenter depends on the (OC)C-C-C(CO) angle. A chelate coordination of the Rmal dianion is realized for 1,1-cyclopropanedicarboxylate anion (~122.9°), while the dimethylmalonate and 1,1-cyclobutanedicarboxylate anions (107.4-110.8°) are characterized by a monodentate coordination. [ABSTRACT FROM AUTHOR]

In prokaryotic genomes, the neighboring genes are often located on the complementary DNA strands and adjoin each other by their 5′- or 3′-ends, or even overlap with their open reading frames. It was suggested that this gene topology has a functional purpose of regulating their expression. For the genes that overlap by their coding 3′-end encoding regions, this assumption has not been confirmed experimentally. In a broad group of bacteria that belong to proteobacteria, this convergent gene arrangement is typical for functionally connected quorum sensing-related genes ' I' and ' R,' which encode synthases of autoinducers, such as N-acyl homoserine lactones and their sensors, respectively. In the present study on the example of overlapping quorum sensing-related genes of plant pathogenic bacterium Pectobacterium atrosepticum SCRI1043, expI, and expR, it was shown that the topology of these genes determines the regulation of their expression. [ABSTRACT FROM AUTHOR]

The reactions of transition metal trimethylacetates [Cu(Piv)(HPiv)], [Ni(OH)(Piv)(HPiv)], [Co(Piv)] (Piv = OCBu) with 1,1-cyclohexanediacetic acid (HChda) neutralized by tetrabutylammonium hydroxide in the presence of 2,2-bipyridine (2,2′-bpy) afford linear trinuclear homometallic complexes [(2,2′-bpy)Cu(Chda)(Piv)]··2EtOH ( 1) and [(2,2′-bpy)M(Chda)(Piv)(EtOH)] (M = Ni ( 2) or Co ( 3)). In molecules of these compounds, anions of both mono- and dicarboxylic acids act as bridges between the transition metal atoms. Compounds 1- 3 were characterized by X-ray diffraction, and their magnetic properties were studied. Spin-spin ferromagnetic interactions dominate in complexes 1- 3 with Cu ( S = 1/2) ( 1) and Co ( S = 3/2) ( 3) ions. [ABSTRACT FROM AUTHOR]

Correlation between structural peculiarities of beta-casein and its chaperon-like activity was investigated using the recombinant forms of the protein containing the cysteine residues in the polypeptide chain. Aggregation of native and modified forms of β-casein was studied, as well as their chaperon-like activity towards alcohol dehydrogenase thermal aggregation. It has been shown that dimeric and oligomeric forms of β-casein, which are formed due to intermolecular disulfide bonds, significantly differ in their physicochemical and chaperon-like properties from monomeric forms. The thermal stability of alcohol dehydrogenase has been found to depend on the β-casein concentration. [ABSTRACT FROM AUTHOR]

The article focuses on the study that examines the novel cytochrome CYP74B1 of flax or Linum usitatissimum. It states that the amino acid sequences of the CYP74 enzymes were compared with different plant species and their conservative domains. It reveals that the sequence of CYP74B1 enzyme has several unique amino acid substitutions despite the enzyme's inclusion in the CYP74B subfamily. It adds that divinyl ether synthase (DES) CYP74B1 of flax is a unique enzyme of the CYP74B subfamily.

The optical limiting efficiency and the possibility of extending the spectral and time ranges of optical limiters based on fullerene-containing media are studied. The optical limiting of pulses of different durations in solutions of C60 and higher fullerenes, the triplet—triplet transfer in multicomponent fullerene-containing solutions, and the electron transfer in the C60-tetramethylbenzidine-perylene system are investigated. [ABSTRACT FROM AUTHOR]

The luminescence of singlet oxygen at wavelengths of 760 and 1270 nm in solutions of fullerene in aerated organic liquids irradiated by high-power short laser pulses and by xenon lamps is considered theoretically. The obtained analytical formulas allow one to determine the lifetimes of the 1Σ O2 and 1Δ O2 oxygen levels, as well as the rate constant of the reaction of generation of singlet oxygen by triplet fullerene in this solution. [ABSTRACT FROM AUTHOR]