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Relatively limited information about promoter structures in Corynebacferium glutamicum has been available until now. With the aim of isolating and characterizing such transcription initiation signals, random Sau3A fragments of C. glutamicum chromosomal DNA and of the corynebacterial phage $GAl were cloned into the promoter probe vector pEKplCm and selected for promoter activity by chloramphenicol resistance of transformed C. glutamicum cells. The nucleotide sequence of ten chromosomal and three phage fragments was determined and the transcriptional start (TS) sites were localized by primer extension analyses. Additionally, the promoters of five previously isolated C. glutamicum genes were cloned and mapped. All of the isolated promoters were also functional in the heterologous host Escherichia coli. A comparative analysis of the newly characterized promoter sequences together with published promoters from C. glutamicum revealed conserved sequences centred about 35 bp (ttGcca) and 10 bp (TA.aaT) upstream of the TS site. The position of these motifs and the motifs themselves are comparable to the -35 and -10 promoter consensus sequences of other Gram-positive and Gramnegative bacteria, indicating that they represent transcription initiation signals in C. glutamicum. However, the C. glutamicum consensus hexamer of the -35 region is much less conserved than in E coli, Bacillus, Lactobacillus and Streptococcus.

New experimental data on the density of 1-butyl-3-methylimidazolium tetrafluoroborate are reported, obtained with a constant-volume apparatus described here in detail. The measurements were conducted along eight isochores at temperatures from (354 to 240) K and at nominal pressures of 1 MPa and from (10 to 60) MPa with a 10 MPa step. The combined uncertainty at the 95 % confidence level of a density measurement is estimated to be less than 1 kg·m−3, i.e., 0.1 %. A Tait-type equation was developed describing the ρ(T, p) dependence. The equation is fitted to the data of the present work and to critically assessed data of other authors compiled from the literature. Values of the coefficient of isothermal compressibility and of isobaric thermal expansion for 1-butyl-3-methylimidazolium tetrafluoroborate were calculated from the correlation equation and compared with experimental data from the literature. An unusual decreasing dependence of the isobaric thermal expansion coefficient on temperature, observed by other authors, was confirmed.

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Simple but highly accurate correlations have been developed for the thermodynamic properties (including density, heat capacity, and speed of sound), viscosity, thermal conductivity, and static dielectric constant of liquid water as a function of temperature at a pressure of 0.1MPa. The calculations may be simply extended to a pressure range from the saturation pressure to 0.3MPa. The temperature range covered in most cases is from 253.15to383.15K; this includes some temperatures where liquid water is metastable. These correlations are designed to reproduce the best available data, which in most cases are described by formulations issued by the International Association for the Properties of Water and Steam (IAPWS). The equations presented here are simple enough to be used in applications such as spreadsheets. They provide a convenient alternative to the more complicated IAPWS formulations in cases where only liquid properties at near-atmospheric pressure are of interest without increasing the uncertainty beyond that of the more complex formulations.