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We investigate low-temperature electronic states of the series of organic conductors $\beta^{\prime\prime}$-(BEDT-TTF)$_4$[(H$_3$O)M(C$_2$O$_4$)$_3$]G, where BEDT-TTF is bis(ethylenedithio)tetrathiafulvalene, and M and G represent trivalent metal ions and guest organic molecules, respectively. Our structural analyses reveal that the replacement of M and G give rise to systematic change in the cell parameters, especially in the $b$-axis length, which has positive correlation with the superconducting transition temperature $T_{\rm c}$. Analyses of temperature and magnetic field dependences of the electrical resistance including the Shubnikov-de Haas oscillations elucidates that the variation of charge disproportionation, effective mass and the number of itinerant carriers, can be systematically explained by the change of the $b$-axis length. The changes of the transfer integrals induced by stretching/compressing the $b$-axis are confirmed by the band calculation. We discuss that electron correlations in quarter-filled electronic bands lead to charge disproportionation and the possibility of a novel pairing mechanism of superconductivity mediated by charge degrees of freedom., Comment: 7 pages, 8 figures

We report high-field magnetotransport measurements on \beta''-(BEDT-TTF)_4[(H_3O)M(C_2O_4)_3]Y, where M=Ga, Cr and Fe and Y=C_5H_5N. We observe similar Shubnikov-de Haas oscillations in all compounds, attributable to four quasi-two-dimensional Fermi-surface pockets, the largest of which corresponds to a cross-sectional area ~8.5\% of the Brillouin zone. The cross-sectional areas of the pockets are in agreement with the expectations for a compensated semimetal, and the corresponding effective masses are ~m_e, rather small compared to those of other BEDT-TTF salts. Apart from the case of the smallest Fermi-surface pocket, varying the $M$ ion seems to have little effect on the overall Fermi-surface topology or on the effective masses. Despite the fact that all samples show quantum oscillations at low temperatures, indicative of Fermi liquid behavior, the sample- and temperature-dependence of the interlayer resistivity suggest that these systems are intrinsically inhomogeneous. It is thought that intrinsic tendency to disorder in the anions and/or the ethylene groups of the BEDT-TTF molecules leads to the coexistence of insulating and metallic states at low temperatures; comparison with other charge-transfer salts suggests that this might be a rather general phenomenon. A notional phase diagram is given for the general family of \beta''-(BEDT-TTF)_4[(H_3O)M(C_2O_4)_3]Y salts, which exhibits several marked similarities with that of the \kappa-(BEDT-TTF)_2X superconductors., Comment: 12 pages, 7 figures, 2 tables

Cytochrome c(3) from Desulfovibrio vulgaris Miyazaki F was successfully expressed in the facultative aerobe Shewanella oneidensis MR-1 under anaerobic, microaerophilic, and aerobic conditions, with yields of 0.3 to 0.5 mg of cytochrome/g of cells. A derivative of the broad-host-range plasmid pRK415 containing the cytochrome c(3) gene from D. vulgaris Miyazaki F was used for transformation of S. oneidensis MR-1, resulting in the production of protein product that was indistinguishable from that produced by D. vulgaris Miyazaki F, except for the presence of one extra alanine residue at the N terminus.

Cytochrome c(3) from Desulfovibrio vulgaris Miyazaki F was successfully expressed in the facultive aerobe Shewanella oniedensis MR-1 under anaerobic, microaerophilic, and aerobic conditions, with yields of 0.3 to 11.5 mg of cytochrome/g of cells.