The role of isochorismate hydroxymutase genes entC and menF in enterobactin and menaquinone biosynthesis in Escherichia coli.

Klebsiella pneumoniae 62-1, a triple mutant impaired in aromatic amino acid biosynthesis (Phe-, Tyr-, Trp-), excretes chorismic acid into the culture broth. When transformed with plasmids harbouring Escherichia coli genes entC or menF the mutant excretes a mixture of both chorismic and isochorismic acid indicating that not only entC but also menF encodes an isochorismate hydroxymutase (isochorismate synthase, EC 5.4.

An isochorismate hydroxymutase isogene in Escherichia coli.

The pivotal step in enterobactin and menaquinone biosynthesis is the conversion of chorismate to isochorismate. Circumstantial evidence pointed to Escherichia coli isochorismate hydroxymutase isogenes being responsible for this conversion. While the gene involved in enterobactin synthesis (entC) was known, the corresponding gene for menaquinone biosynthesis (menF) was not but has now been identified and sequenced.

[New aspects in the diagnosis of herpes simplex virus encephalitis--case reports and virologic findings].

Herpes simplex virus (HSV) is one of the most common causes of severe necrotizing encephalitis in men. Without adequate acyclovir treatment it has a mortality rate of 70%. An early, reliable virological diagnosis is therefore essential.

The diagnostic significance of the polymerase chain reaction and isoelectric focusing in herpes simplex virus encephalitis.

In this study, serum and CSF samples of 55 neurological patients have been examined to confirm the diagnosis of herpes simplex virus encephalitis (HSVE). Different methods were applied, including serological titer evaluations, determination of intrathecally-produced HSV-specific antibodies by isoelectric focusing with affinity immunoblotting (IEF), as well as HSV-specific ELISA and HSV-specific polymerase chain reaction (PCR). The results of IEF and PCR have been compared and contrasted to develop general directions for virological diagnosis of HSVE.

Methodological modifications for accurate and efficient determination of contaminant biodegradation in unsaturated calcareous soils.

Many techniques for quantifying microbial biodegradation of C-labeled compounds use soil-water slurries and trap mineralization-derived CO(2) in solution wells suspended within the incubation flasks. These methods are not satisfactory for studies of arid-region soils that are highly calcareous and unsaturated because (i) slurries do not simulate unsaturated conditions and (ii) the amount of CO(2) released from calcareous soils exceeds the capacity of the suspended well. This report describes simple, inexpensive methodological modifications for quantifying microbial degradation of [C]benzene and 1,2-dichloro[U-C]ethane in calcareous soils under unsaturated conditions.

[Andrological findings in hemicastration, lack of a testis, and reduced testicular volume].

In a catamnestic study an analysis of the clinical results as well as of the spermatograms are reported on 545 andrological patients with "atrophy" (that means reduced testis volume) or absence of one testis and a contralaterally normal developed testis. It can be demonstrated that there do not exist any differences concerning the size and consistency of the present testis and with regard to absence or lost of one testis (hemicastration). In case of testicular atrophy exists a more disadvantageous reproductive function.

[Does sodium hydroxide soda help in oral candidiasis?].

The following results proof: in the case of Candida albicans-infection sodium-hydrogen-carbonate-treatment does not work.

Initial effects of the mount st. Helens eruption on nitrogen cycle and related chemical processes in ryan lake.

Ryan Lake, a 1.6-hectare basin lake near the periphery of the tree blowdown area in the blast zone 19 km north of Mount St. Helens, was studied from August to October 1980 to determine the microbial and chemical response of the lake to the eruption.

Effects of progesterone on some enzymes of fat and carbohydrate metabolism in rat liver.

The known effect of progesterone on carbohydrate metabolism prompted a study of some of the hepatic "lipogenic" and "gluconeogenic" enzymes in rats treated with progesterone. Several enzymes providing lipid precursors (phosphofructokinase, malic enzyme, glucose-6-phosphate dehydrogenase, and citrate cleavage enzyme) showed increased specific activity. These changes may represent insulin effects.

Relationship between levels of blood lipids, vitamins C, A, and E, serum copper compounds, and urinary excretions of tryptophan metabolites in women taking oral contraceptive therapy.

To evaluate which women using oral contraceptive agents might be at risk, biochemical indices known to be affected by the estrogens and progestogens were studied in women who take oral contraceptive agents, in women who do not use oral contraceptive agents, in women in third trimester of pregnancy and 6 weeks after parturition, and in men with normal and high blood lipid levels. The most consistent changes due to oral contraceptive agents were in serum levels of copper, triglycerides, and vitamin A and in the urinary excretion of xanthurenic acid and niacin derivatives before and after a tryptophan load test. There was only a slight suggestion, with no statistical significance, that serum vitamin C levels decreased when the serum levels of ceruloplasmin were high.