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Pseudomonas is the bacterial genus of Gram-negative bacteria with the highest number of recognized species. It is divided phylogenetically into three lineages and at least 11 groups of species. The Pseudomonas putida group of species is one of the most versatile and best studied. It comprises 15 species with validly published names. As a part of the Genomic Encyclopedia of Bacteria and Archaea (GEBA) project, we present the genome sequences of the type strains of five species included in this group: Pseudomonas monteilii (DSM 14164T), Pseudomonas mosselii (DSM 17497T), Pseudomonas plecoglossicida (DSM 15088T), Pseudomonas taiwanensis (DSM 21245T) and Pseudomonas vranovensis (DSM 16006T). These strains represent species of environmental and also of clinical interest due to their pathogenic properties against humans and animals. Some strains of these species promote plant growth or act as plant pathogens. Their genome sizes are among the largest in the group, ranging from 5.3 to 6.3 Mbp. In addition, the genome sequences of the type strains in the Pseudomonas taxonomy were analysed via genome-wide taxonomic comparisons of ANIb, gANI and GGDC values among 130 Pseudomonas strains classified within the group. The results demonstrate that at least 36 genomic species can be delineated within the P. putida phylogenetic group of species.

Two novel supramolecular heteroleptic complexes [Pb2L2(NO3)2]n (1) and {[Pb3L3](ClO4)3}n·3.25nH2O (2·3.25nH2O), obtained from N′-(piperidine-1-carbonothioyl)picolinohydrazonamide (HL) and Pb(NO3)2 or Pb(ClO4)2 in aqueous methanol are reported. A crucial role of the auxiliary ligand (NO3−vs. ClO4−) was revealed as a driving force for the formation of the resulting architecture of complexes, which, in turn, are dictated by the formation of tetrel bonds. Complex 1 is constructed from heteroleptic dinuclear centrosymmetric species [Pb2L2(NO3)2], which, in turn, are formed from the heteroleptic mononuclear symmetry related [PbL(NO3)] units, linked through a pair of bonds formed between the metal cations and the thioamide nitrogen atoms. The metal cations form a weaker tetrel bond with the symmetry related nitrate atoms, yielding a 1D polymeric chain structure. These chains are interlinked through N–H⋯O hydrogen bonds, formed between the covalently coordinated nitrate oxygen atom and the NH2 hydrogen atom, yielding a 2D supramolecular architecture. Complex 2·3.25nH2O is constructed from the trinuclear species [Pb3L3](ClO4)3. The trinuclear cation is constructed from three [PbL]+ cations interlinked through two Pb–S and two Pb–N bonds, formed with the thiocarbonyl sulfur atoms and the amide nitrogen atoms. The cations [Pb3L3]3+ are interlinked through two Pb–N and two Pb–S bonds yielding a 1D supramolecular polymeric cationic chain {[Pb3L3]3+}n. The two metal cations corresponding to two [PbL]+ units, linked through a pair of the Pb–S bonds, are additionally bridged by two oxygen atoms of one of the perchlorate anions with the formation of two Pb⋯O tetrel bonds. The coordination spheres of the metal cations are filled by one of the oxygen atoms of two different perchlorate anions with the formation of tetrel bonds. One of these perchlorates also forms the N–H⋯O hydrogen bond within the trinuclear unit [Pb3L3](ClO4)3. 1D supramolecular chains {[Pb3L3]3+}n are interlinked through a myriad of hydrogen bonds formed by the perchlorate anions and crystallized water molecules. The tetrel bonds involving the counterions (Pb⋯O) have been also analysed by DFT calculations via a MEP surface plot and 2D maps of electron localization function (ELF), Laplacian of electron density (∇2ρ) and reduced density gradient (RDG), confirming their noncovalent nature. [ABSTRACT FROM AUTHOR]

(ClImDipp)P–P(Dipp)˙ (1˙), a rare example of a neutral, mixed substituted diphosphene radical, has been prepared by reduction of (ClImDipp)PP(Dipp)[OTf] (2[OTf]) and (ClImDipp)PP(Cl)(Dipp) (3) with cobaltocene (CoCp2) (ClImDipp = 4,5-dichloro-1,3-bis(1,3-diisopropylphenyl)-imidazol-2-yl, Dipp = 2,6-diisopropylphenyl). Radical compound 1˙ readily activates white phosphorus (P4), resulting in the formation of an intriguing octaphosphane butterfly compound P8(ClImDipp)2(Dipp)2 (4). [ABSTRACT FROM AUTHOR]

In this contribution, a novel binuclear heteroleptic complex [Pb2L2(CO3)]·2CH3CN·2MeOH (1·2CH3CN·2MeOH) is reported, which was fabricated by electrochemical oxidation of a lead anode under an ambient atmosphere in a CH3CN : MeOH solution of N′-isonicotinoylpyrazine-2-carbohydrazonamide (HL). The CO32− anion was produced from the conversion of aerial CO2 by the Pb2+–L complex system under electrochemical conditions. In the structure of 1, ligand L exhibits a tridentate pincer-like N,N′,O-coordination mode, while the CO32− anion exhibits a tetradentate bridging coordination mode with one of the oxygen atoms exhibiting a bridging μ-coordination mode. The metal cations in the structure of 1 are in a five-membered N2O3 coordination environment, formed by covalent bonds. The molecular structure of 1·2CH3CN·2MeOH is stabilized by a pair of intermolecular Pb⋯N tetrel bonds formed with one of the NH2 nitrogen atoms of an adjacent complex molecule and with the acetonitrile nitrogen atom, and one Pb⋯O tetrel bond formed with the carbonyl oxygen atom of the other adjacent complex molecule, yielding a 2D supramolecular sheet. This sheet is further stabilized by intermolecular N–H⋯Nacetonitrile and N–H⋯Ocarbonate hydrogen bonds and πPyrazine⋯πPyridine interactions. The optical properties of the complex were revealed by UV-vis spectroscopy and spectrofluorimetry in MeOH. It was established that the described complex is emissive upon excitation at 340 nm with a broad band from about 500 nm to 780 nm with a maximum at ∼580 nm, accompanied by a shoulder at ∼620 nm. The CIE-1931 chromaticity coordinates of (0.28, 0.36) fall within the white gamut of the chromaticity diagram. Thus, complex 1 is a single-component white light-emitting phosphor. [ABSTRACT FROM AUTHOR]

With the objective of gaining insight into the modulation of the reduction potential of the Ni(II / I) couple, we have synthesized two mononuclear nickel(II) complexes, NiLen (H2Len = N,N′-bis(3-methoxysalicylidene)-1,2-diamino-2-methylpropane) and NiLpn (H2Lpn = N,N′-bis(3-methoxysalicylidene)-1,3-diamino-2,2-dimethylpropane) of two N2O4 donor ligands and recorded their cyclic voltammograms. Both the nickel complexes show reversible reduction processes for the Ni(II / I) couple in acetonitrile solution but the reduction potential of NiLpn (E1/2 = −1.883 V) is 188 mV more positive than that of NiLen (E1/2 = −2.071 V). In the presence of redox inactive metal ions (Li+, Na+, K+, Mg2+, Ca2+ and Ba2+), the reduction potentials are shifted by 49–331 mV and 99–435 mV towards positive values compared to NiLen and NiLpn, respectively. The shift increases with the decrease of the pKa of the respective aqua-complexes of the metal ion but is poorly co-linear; however, better linearity is found when the shift of the mono- and bi-positive metal ion aqua complexes is plotted separately. Spectrophotometric titrations of these two nickel complexes with the guest metal ions in acetonitrile showed a well-anchored isosbestic point in all cases, confirming the adduct formation of NiLen and NiLpn with the metal ions. Structural analysis of single crystals, [(NiLen)Li(H2O)2]·ClO4 (1), [(NiLpn)Li(H2O)]·ClO4 (2), [(NiLpn)2Na]·BF4 (3) and [(NiLpn)2Ba(H2O)(ClO4)]·ClO4 (4), also corroborates the heterometallic adduct formation. The orbital energies of the optimised heterometallic adducts from which electron transfers originated were calculated in order to explain the observed reduction process. A strong linear connection between the calculated orbital energies and the experimental E1/2 values was observed. According to MEP and 2D vector field plots, the largest shift for divalent metal ions is most likely caused by the local electric field that they impose in addition to Lewis acidity. [ABSTRACT FROM AUTHOR]

The co-crystallization of S-(CF3)-dibenzothiophenium ("Umemoto" – abbreviated Ume) cations and polycyanometalates with different coordination geometries yields a large structural variety of supramolecular assemblies. In the case of [Ume+]2[Ni(CN)4]2−·CH2Cl2 all four cyanide groups of the square-planar dianion act as chalcogen bond acceptors whereas the sulfur atoms of the Umemoto cations act as biaxial chalcogen bond donors. For tetrahedral [Zn(CN)4]2− a more complex assembly of four Umemoto cations and two dianions is observed. In the case of [Ume+]3[Fe(CN)6]3−·CH2Cl2 one Umemoto cation even acts as a triaxial chalcogen bond donor whereas only 4 out of the 6 cyanide groups act as chalcogen bond acceptors. For [Ume+]3[W(CN)8]3− a polymeric chain structure is observed in which all Umemoto cations act as biaxial chalcogen bond donors. DFT investigations focus on the physical nature of the chalcogen bonds, encompassing energetic assessments, MEP surface plots, QTAIM, and NBO analysis, shedding light on the nature of chalcogen donor–acceptor interactions. The energetic results evidence that total contributions of chalcogen bonds in different synthons range from −7.6 to −16.3 kcal mol−1, surpassing that of hydrogen bonds that range from −4.9 to −11.8 kcal mol−1. [ABSTRACT FROM AUTHOR]