Purification and enzymatic properties of glyoxylate reductase II from baker's yeast

Glyoxylate reductase II was purified about 2,400-fold from a cell extract of baker's yeast by protamine sulfate treatment, and column chromatographies on DEAE-cellulose, hydroxylapatite, Sephadex G-150, and phosphocellulose. The purified enzyme was electrophoretically homogeneous. The molecular weight was determined to be approximately 65,000 by gel filtration. The enzyme was greatly stabilized by the addition of 20% (v/v) glycerol. It catalyzed the reduction of glyoxylate and hydroxypyruvate and was specific for NADPH as an electron donor, but showed slight affinity towards NADH. The Michaelis constants for glyoxylate, hydroxypyruvate, NADPH, and NADH were found to be 16mM, 1.4 mM, 5.7 microM, and 0.43 mM, respectively. The enzyme was inhibited by p-chloromercuribenzoate (PCMB) and iodoacetate, but inhibition was prevented by dithiothreitol (DTT) or L-cysteine. The reduction of glyoxylate and hydroxypyruvate was not stimulated by anions.

Purification and some properties of uridine diphosphate N-acetylglucosamine pyrophosphorylase from Neurospora crassa

Uridine diphosphate N-acetylglucosamine pyrophosphorylase (EC. 2.7.7.23) of Neurospora crassa has been purified approximately 210-fold with dithiothreitol as the stabilizing agent by use of chromatographic techniques. The enzyme preparation appeared to be homogeneous when subjected to electrophoresis. The molecular weight was estimated as approximately 37 000 by gel filtration. The enzyme had an isoelectric point around pH 4.4. Maximum activity of the enzyme was observed at pH 7.5. The enzyme required Mg2+, which may be replaced by other divalent cations such as Mn2+ and Co2+ for lesser degrees of effectiveness. The enzyme was strictly specific for UDP-N-acetylglucosamine as the substrate. The estimated values of Km were 2.2 mM for UDP-N-acetylglucosamine and 5.4 mM for inorganic pyrophosphate. The enzyme activity was highly stimulated by the addition of dithiothreitol or dithioerythritol but was lost by sulfhydryl inhibitory reagents.

Purification and properties of glyoxylate reductase I from baker's yeast

The purification and properties of NADPH-linked glyoxylate reductase [EC 1. 1. 1. 79] from baker's yeast were studied. Two active fractions (peak I and peak II) were isolated by DEAE-cellulose column chromatography. The peak I fraction was purified to homogeneity by the criteria of disc gel electrophoresis and tentatively designated glyoxylate reductase I. Its molecular weight was calculated to be 31,000 from gel filtration measurements. The enzyme reduced glyoxylate 7 times faster than hydroxypyruvate and was specific for NADPH. The enzyme showed optimum activity between pH 5.5 and 7.2. The Michaelis constants for glyoxylate and NADPH were found to be 13 mM and 4 microM, respectively. The enzymic activity was not significantly affected by anions, except for nitrate and iodide, which were inhibitory.

Topical heat therapy for cutaneous chromomycosis

An aged man with a large scaly plaque over the left buttock was successfully treated by local heat therapy using an electric bed-warmer with a surface temperature of 46 degrees C. Clinically, the lesion involuted completely after two months of treatment. This was concomitantly confirmed by histopathological and mycological studies of biopsy specimens obtained from the lesion at an interval of several weeks. The isolated fungus strain of Fonsecaea pedrosol could grow at 37 degrees C on Sabouraud's dextrose agar, but was totally eradicated 24 hours after the culture was incubated at 46 degrees C. We consider that local heat therapy carried out under strict supervision is a quite effective treatment for chromomycosis. Moreover, it can be performed safely and without much discomfort to patients, and can yield satisfactory results in a relatively short time.

[Effect of fosfomycin-calcium on reproductive performance of rat and rabbit: teratogenicity test (author's transl)]

The teratogenicity study of fosfomycin-Ca (FOM-Ca) was undertaken in Wistar strain rats and JW strain rabbits. Rats were treated orally at dose levels of 140,700 and 1,400 mg/kg/day from 7th to 17th day of gestation, and rabbits were treated orally at dose levels of 80, 140 and 420 mg/kg/day from 6th to 18th day of gestation. In the case of rats, two-thirds of pregnant mothers in each group were sacrificed on 20th day of gestation and then their fetuses were examined for external, visceral and skeletal observation. The remaining mothers were allowed to deliver naturally, and then their offsprings were examined for postnatal development. In the case of rabbits, all pregnant mothers were sacrificed on 29th day of gestation and their fetuses were examined. No effect of FOM-Ca treatment to rat and rabbit mothers was found except soft stool was seen with maximum dose in rats. Dead or resorbed rate of fetuses increased, external anomalies (short tail, abdominal hernia) were found and skeletal anomalies slight increased with maximum dose in rats. However, there was no significant difference from the control or background data. While, no effect of FOM-Ca treatment was observed in rabbits and rat offsprings. Consequently, it can be concluded that FOM-Ca has no teratogenicity effects on rats and rabbits.

[Effect of fosmocyin-Na on reproductive performance of rats and rabbits. I. Teratogenicity test (author's transl)]

The teratogenicity study of fosfomycin-Na (FOM-Na) was undertaken in Wistar rats and New Zealand white rabbits. Rats were treated intraperitoneally at dose levels of 125, 250, 750 and 1,500 mg/kg/day from day 7 to day 17 of gestation, and rabbits were treated intravenously at dose levels of 80, 100, 200, 400 and 800 mg/kg/day from day 6 to day 18 of gestation. In the case of rats, two-thirds of pregnant mothers in each group was sacrificed on day 20 of gestation and then their fetuses were examined for external, visceral and skeletal observation. The remaining mothers were allowed to deliver naturally, and then their offsprings were examined for postnatal development. In the case of rabbits, all pregnant mothers were sacrificed on day 29 of gestation and their fetuses were examined. Body weight of rat mothers during gestation were decreased and 4 mothers were dead until day 20 of gestation in the maximum dose. In this dose, foetal toxicity was recognized too. However, external, visceral and skeletal anomalies related with FOM-Na treatment were not observed in all groups. No effect on development of offsprings was observed. No effect of treatment of FOM-Na to rabbits was found except foetal body weight was slightly decreased in the maximum dose.

[Effect of fosfomycin-Na on reproductive performance of rats. II. Fertility test (author's transl)]

The fertility study of fosfomycin-Na (FOM-Na) was undertaken in Wistar rats. FOM-Na was administered intraperitoneally at dose levels of 125, 250, 750 and 1,500 mg/kg/day. The male rats were continuously treated with FOM-Na from 63 days before mating and the females were treated from 14 days before mating. The males and females were treated through the mating period and then the pregnant rats were treated until 7 days of gestation. All pregnant rats were sacrificed on day 20 of gestation and then their fetuses were examined for external, visceral and skeletal observation. Mean body weight of males decreased and 6 males and 3 females died in the maximum dose. However, no significant differences were found between treated groups and the control with regard to fertility rate and pregnant rate. External, visceral and skeletal anomalies related with FOM-Na treatment were not observed. In this experiment, no effects of FOM-Na for reproductive performance in rats were observed.

Spectrophotometric determination of pyridoxal and pyridoxal 5'-phosphate with 3-methyl-2-benzothiazolone hydrazone hydrochloride, and their selective assay

A spectrophotometric method with 3-methyl-2-benzothiazolone hydrazone hydrochloride was developed for the determination of pyridoxal and pyridoxal 5'-phosphate, and for the selective determination of each in the presence of the other. Pyridoxal and pyridoxal 5'-phosphate react with the reagent to yield the azine derivatives, which give characteristic absorption spectra. The highest extinction values are obtained when pyridoxal and pyridoxal 5'-phosphate are incubated at pH values of about 3.4 and 8.0 respectively; their maxima are at 430nm. (in 2.74x10(4)) and 380nm. (in 2.24x10(4)) respectively. The azine of pyridoxal is only slightly soluble under the neutral and alkaline conditions, whereas that of pyridoxal 5'-phosphate is substantially insoluble in the acid pH range. This difference in solubility of the azines made possible the selective determination of pyridoxal and pyridoxal 5'-phosphate. alpha-Oxoglutarate and pyruvate are among the substances shown not to interfere with the assay of pyridoxal; their derivatives absorb appreciably only at wavelengths below 420nm. For the assay of pyridoxal 5'-phosphate in the presence of these compounds measurement at 390nm. is necessary.