In vitro transcription analysis has shown that only RNA polymerase containing an alternative sigma subunit, E , activates transcription from one of the rpoH promoters and the htrA promoter. The location of the rpoE gene encoding E on the Escherichia coli chromosome has recently been established, but no rpoE mutant has yet become available for phenotypic testing. We cloned the rpoE gene from the -ordered clones of the E. coli genome and confirmed that the reconstituted RNA polymerase containing the gene product (E E ) can transcribe htrA in vitro. We constructed an rpoE-defective strain by gene disruption using the cloned rpoE gene. We demonstrate that expression of htrA is completely dependent on the rpoE gene in vivo and that the rpoE gene is essential for bacterial growth at high temperature.In Escherichia coli, RNA polymerase consists of the subunits of 2␣, ␤, ␤Ј, and a specific . The subunit directs RNA polymerase to initiate transcription at promoter sites on the DNA (6). The primary factor, 70 encoded by rpoD, is responsible for transcription of the majority of the genes expressed during exponential growth. In addition, alternative factors direct transcription of sets of genes whose products are needed for specific functions, such as nitrogen fixation, flagellum synthesis, heat shock response, and stationary-phase growth (4).The activities of two alternative factors, 32 and E , increase after the cell is exposed to a high temperature or ethanol (2,3,5,21,25,28). RNA polymerase containing 32 (E 32 ) transcribes the heat shock genes whose products are related to chaperones and proteases (29). The functions of many of these heat shock proteins are involved in binding to cytoplasmic proteins and assist the cytoplasmic proteins in folding or unfolding (7,15,22,26) and in protecting the cell from severe stresses such as exposure to 10% ethanol or a 50ЊC temperature (18). Using an in vitro transcription assay, Erickson and Gross (2) and Wang and Kaguni (25) have independently identified the E subunit that is essential for transcription from one (rpoHp 3 ) of the promoters of rpoH encoding 32 and the promoter of htrA encoding a periplasmic endopeptidase essential for growth at high temperatures. Mecsas et al. (16) have proposed that the E regulon is involved in the processes that function in the extracytoplasmic compartments.

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Treatment of Escherichia coli and Salmonella typhimurium cells with a low dose of hydrogen peroxide induces expression of a large number of genes, and confers resistance to oxidative stresses. The oxyR gene encodes a positive regulatory protein for a subset of these genes involved in the defense against oxidative damage. We cloned a DNA fragment that contains the E. coli oxyR region on a plasmid vector, and analyzed the nucleotide sequence of the gene. The amino acid sequence of OxyR protein, deduced from the nucleotide sequence, shows a high degree of homology to the sequences of a number of bacterial activator proteins including LysR, CysB, IlvY, MetR and NodD. The product of the oxyR gene identified by the maxicell procedure was a 34 kDa protein, which agrees with the size predicted from the nucleotide sequence of the gene.

Light to moderate alcohol consumption seems to have an important influence on BP in both young and middle-aged Japanese men.

, but also in their Japanese counterparts [4][5][6][7] . Psychological distress is considered to be a risk factor for MetS. A cross-sectional study of 87 monozygotic and 86 dizygotic male twin pairs in the US showed that depressive symptoms were associated with metabolic risk factors such as body mass index, waistto-hip ratio, mean arterial pressure, triglycerides and glucose 8) . A 7-year prospective study of 425 middleaged women in the US showed that depressive symptoms were predictive of a risk of MetS 9). A 14-year large-scale prospective study of 10,308 middle-aged men and women in England showed that chronic work stress was associated with a risk of MetS 10) . Finally, a recent 15-year prospective study of 523 middle-aged pre-menopausal women in the US also indi-