Effect of undecanoic acid on germination of microconidia of wild and undecanoic acid resistant mutant of trichophyton rubrum

Effects of undecanoic acid (UDA) on germination of microconidia and elongation of germ tubes in UDA sensitive (uda _s) wild type Trichophyton rubrum and UDA resistant (uda _r) mutant derived from it, were studied. UDA inhibited conidial germination of uda _s and uda _r strains at 30 g/ml and 120 g/ml respectively which were minimum inhibitory concentrations of UDA for these two strains. When spores from both uda _s and uda _r were germinated in presence of subinhibitory concentration of UDA, germ tube growth was short. The elongation of germ tubes of spores pregerminated in absence of UDA was also inhibited by dose of UDA not sufficient to inhibit germination.     

beta-Adrenergic receptors in rat skeletal muscle. Effects of thyroidectomy.

Thyroid hormones may participate in the regulation of beta-adrenergic receptors in skeletal muscle sarcolemmal membrane. Since skeletal muscles are not innervated by sympathetic nerve endings, the biochemical mechanism involved in the control of beta-adrenergic receptors by thyroid hormones appears to be mediated by thyroid-induced regulation of serum levels of catecholamines.     

A new method of preparing Ca2+-ATPase from sarcoplasmic reticulum: extraction with octylglucoside.

A fast method for preparing Ca2+-ATPase from rabbit muscle sarcoplasmic reticulum was devised. The method involves extracting extrinsic membrane proteins with the non-ionic detergent octylglucoside at high salt concentration. A Ca2+-ATPase of consistently high specific activity (about 25 mumoles/mg.min) is found in the insoluble residue. The method was optimized with respect to the concentrations of detergent and salt, pH, and other extraction conditions. By the criteria of the protein pattern in SDS-polyacrylamide gel electrophoresis, dependence of the hydrolytic activity on the presence of Ca2+, and the phosphoprotein formation, the preparation is identical with the Ca2+-ATPase isolated previously by MacLennan [10] and other authors. The main advantages of the new method are its rapidity, its reliability, and the high specific activity of the purified enzyme.     

Production of l-glutamic acid by aBacillus sP

A strain ofBacillus cereus var.mycoides isolated from Burdwan soil producesl-glutamate in the medium. The strain is able to grow and produce in a synthetic medium but supplementation with casamino acid or yeast extract improves the yield. Maintenance of pH of the fermentation medium near neutrality prolongs the active growth period and improves the yield. Glucose and ammonium nitrate were found to be most suitable carbon and nitrogen sources, respectively. Cane sugar molasses (as a substitute for glucose) significantly stimulated the growth but glutamate production was less. Various B vitamins stimulate the growth and glutamate yield. The yield of glutamate under optimal condition is 5.2 g/l.     

Estimation of dehydroascorbic acid in blood of diabetic patients.

A modified method has been described for the estimation of ascorbic acid (AA) and dehydroascorbic acid (DHA) in blood and plasma. DHA is practically absent in the blood of normal human beings. On the other hand, diabetic patients have a persistently high blood DHA level. The DHA from diabetic blood has been isolated as the 2,4-dinitrophenylhydrazone derivative and identified by thin-layer chromatography and spectrophotometry.     

Metabolism of sitosterol by a Pseudomonas species.

Fermentation of sitosterol by a Pseudomonas species (SK-25) resulted in the formation of 5-stigmastene-3 beta, 7 alpha-diol; 5,6 alpha-epoxy-5 alpha-stigmastan-3 beta-ol; 5,6 beta-epoxy-5 beta-stigmastan-3 beta-ol and 5 alpha-stigmastan-3 beta, 5,6 beta-triol. The metabolites were characterized by a variety of conventional chemical and spectrometric techniques.     

Simultaneous occurrence of pregnancylike lobuloalveolar morphogenesis and casein-gene expression in a culture of the whole mammary gland

Summary Entire second thoracic mammary glands of estrogen- and progesterone-treated immature virgin BALB/c mice were stimulated to pregnancylike lobuloalveolar morphogenesis after 6 days of incubation with insulin (5 μg/ml), aldosterone (1 μg/ml), growth hormone (5 μg/ml), cortisol (5 μg/ml), and prolactin (80 ng/ml, present as a contaminant in 5 μg/ml growth hormone). The alveolar growth in the glands, as judged by morphological studies, was accompanied by an increase in cell number as a function of incubation time in the hormonal medium. Hybridization of the total RNA from these glands to the casein mRNA specific complementary DNA probe (cDNA_csn) revealed that the level of casein mRNA rises from 0.00012 to 0.005% between 1 and 6 days of incubation. Estimates showed that the concentration of casein mRNA per cell rises 17-fold from 70 molecules on Day 1 to 1200 molecules on Day 6, whereas the number of epithelial cells increases only twofold during the same incubation time. When the growth hormone preparation was totally replaced by 80 ng of prolactin during the 6-day incubation, casein-mRNA levels were found to be 0.0083%. These results demonstrate that a pregnancy-like morphogenesis and concurrent expression of the casein gene in vitro can be achieved in a controlled hormone environment containing high cortisol and low prolactin concentrations. This one-step mammogenesis-lactogenesis culture model should be useful for studying the mechanisms of hormonal regulation of casein-gene expression observed in prepartum mammary gland in vivo. This work was supported by Department of Health, Education and Welfare Grants CA11058 and CA25304 from the National Cancer Institute.     

Fluorescence studies on the interaction of the tumor promoter phorbol myristate acetate and related compounds with rat liver plasma membranes.

The interaction of the potent tumor-promoting agent phorbol myristate acetate (PMA) with purified rat liver plasma membranes suspended in phosphate-buffered saline (PBS), pH 7.4, was studied by fluorescence spectrophotometry. Exposure of membranes to PMA caused up to 21% decrease of the native membrane emission, i.e. the fluorescence of both tryptophan and tyrosine, compared to non-treated membranes. The decrease in the membrane emission varied with both the PMA and the membrane concentration. Treatment of rat liver plasma membranes with biologically less active analogs of PMA, phorbolol myristate acetate (PHMA) and 4a alpha-phorbol didecanoate (4a alpha-PDD), resulted in a 5-10% decrease of the native membrane emission. These studies suggest that PMA causes alterations in membrane structure which are due, at least in part, to conformational changes in the membrane proteins.     

A semi-defined medium for culturing Nomuraea rileyi

A semi-defined medium was successfully used to culture several natural and mutant isolates of the entomopathogenic fungus, Nomuraea rileyi. The medium contains only two complex ingredients at very low levels, yet permits germination and mycelial growth of N. rileyi. The medium also facilitates recovery and detection of hydrolytic enzymes. Use of the formulation could simplify nutritional, biochemical and physiological studies with N. rileyi and also might be used to culture other entomopathogenic fungi.This article reports the results of research only. Mention of a proprietary product does not constitute an endorsement or a recommendation for its use by USDA.