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Serpens flexibilis was proposed in 1977 and approved in 1980 without the 16S rRNA gene sequence information. The sequence of S. flexibilis became available in 2010, after the publication of Pseudomonas tuomuerensis in 2009. Our preliminary phylogenetic analyses indicated that these two strains share high sequence similarity and therefore showed strong potential to be united into a single species. To clarify the taxonomic status of the two species, a polyphasic taxonomy study was conducted including whole genome sequencing. The value of average nucleotide identity (ANI) and digital DNA-DNA hybridization (dDDH) between the genome sequences of S. flexibilis ATCC 29606 T and P. tuomuerensis JCM 14085 T were 98.1% and 89.0%, respectively. The phenotypic and chemotaxonomic properties including enzymatic activities, substrate utilization profiles, and fatty acids, supported that the two taxa have no pronounced difference and should thus constitute a single species. Therefore, we propose to transfer Serpens flexibilis Hespell 1977 to the genus Pseudomonas as Pseudomonas flexibilis comb. nov. (type strain = ATCC 29606 T ), with Pseudomonas tuomuerensis Xin et al . 2009 as a later heterotypic synonym of Pseudomonas flexibilis . [ABSTRACT FROM AUTHOR]

Vibrio cholera, the causal agent of cholera, also occupies an autochthonous aquatic inhabitant. The current, seventh cholera pandemic is linked to O1 El Tor biotype and O139 serogroups. In the last decades, we have witnessed a shift involving genetically and phenotypically varied pandemic clones in Asia and Africa. Recent comparative genomic studies have identified a large ‘mobilome’, or composed of mobile genomic islands in V. cholerae. All seventh pandemic isolates have highly related genome sequences, but they can be differentiated by set of these genomic islands. A consequence of the extensive lateral gene transfer is that classically important diagnostic markers, such as serotype and biotype, are not reliable and new methods based on genomic sequences are required. [ABSTRACT FROM AUTHOR]

Abstract The harsh conditions in Victoria Land, Antarctica have formed a simple ecosystem dominated by microbes that use rocks as shelters to avoid environmental stressors. The area is composed of basement rocks that illustrate the history of complex deformation, thus it is highly valuable not only in perspectives of geology but also in biological aspects. Because this region is inhospitable to higher-level organisms and receives least external influences, it can be an ideal environment to investigate the relationship between rock-inhabiting bacterial communities and environmental factors. In such conditions, inorganics dissolved from minerals can be considered as key factors influencing rock-inhabiting bacterial communities. Thus, the present study attempted to explore rock-inhabiting bacterial communities throughout Victoria Land, to identify environmental parameters that are more influential on bacterial community compositions, and to investigate latitudinal gradients in environmental parameters and rock-inhabiting bacterial communities. The results suggested that (i) rock-inhabiting bacterial communities in Victoria Land predominately consisted of either Actinobacteria or Proteobacteria ; (ii) latitudinal gradients in rock-inhabiting bacterial community compositions and some environmental parameters were observed; (iii) latitude, pH, nitrate, and sulfate significantly correlated with the dominant phyla; and (iv) the Classification and Regression Tree (CART) analysis demonstrated that latitude, pH, and sulfate concentrations could explain the dominant phylum with 89% accuracy. These findings can provide important insight into the link between environmental factors and rock-inhabiting bacterial community compositions in conditions with extremely cold temperatures and high levels of radiation, which could also be of interest in astrobiology. Graphical abstract Unlabelled Image Highlights • Antarctic rock is a less studied ecosystem due to poor logistics and accessibility. • Relationships between lithic bacteria and the environment are not well understood. • MiSeq and statistical analyses were conducted for 56 rock samples from Antarctica. • Latitude was significantly correlated with the dominant phyla, pH, and NO 3 -. • The CART model classified the dominant phylum with 89% accuracy. [ABSTRACT FROM AUTHOR]

Abstract We investigated the charge generation mechanism of electrically doped organic semiconductors (OSs) by electron spin resonance (ESR) analysis. ESR spectroscopy was used to successfully evaluate the radical density of p -doped OSs to estimate the charge transfer efficiency (CTE) of various doped systems. The results showed that the CTE is efficient close to 100% if the dopant molecules are homogenously dispersed and the energy difference (ΔE) between the highest occupied molecular orbital (HOMO) level of the host molecule and lowest unoccupied molecular orbital (LUMO) level of the p-dopant is large. The charge separation efficiency to form free carriers from the radicals is rather low (less than 12% in this study) and is a dominant factor controlling the charge generation efficiency (CGE). An organic dopant molybdenum tris[1,2-bis(trifluoromethyl)ethane-1,2-dithiolene] turns out to be an efficient dopant with the CGE of 9.7% due to high CTE originating from homogenous dispersion of the organic p-dopants and low LUMO level, i.e., large ΔE. Graphical abstract Image 1 Highlights • Films of organic semiconductors (OSs) are doped with an organic p -dopant. • Charge generation (CG) is studied by electron spin resonance spectroscopy. • High CG efficiency of 9.7% is achieved for a film with 2 mol% p -dopant. • The efficiency of charge transfer is 83% while that of charge separation is 11.6%. • High CG efficiency is because of homogeneous dispersion of p -dopant in OS matrix. [ABSTRACT FROM AUTHOR]

Abstract: Pyridoxal kinase (PK) catalyses the phosphorylation of vitamin B6 to pyridoxal-5′-phosphate (PLP). A human brain PK gene was fused with a gene fragment encoding the HIV-1 Tat protein transduction domain (RKKRRQRRR) in a bacterial expression vector to produce a genetic in-frame Tat–PK fusion protein. The expressed and purified Tat–PK fusion proteins transduced efficiently into PC12 cells in a time- and dose-dependent manner when added exogenously in culture media. Once inside the cells, the transduced Tat–PK proteins showed catalytic activity and are stable for 48 h. The intracellular concentration of PLP, which is known as a biologically active form of vitamin B6, was increased by pre-treatment of Tat–PK to the PC12 cells. Those results suggest that the transduction of Tat–PK fusion protein can be one of the ways to regulate the PLP level and to replenish this enzyme in the various neurological disorders related to vitamin B6. [Copyright &y& Elsevier]