A resting cell system was used to study the sites of inhibition by NH4+ of protylonolide biosynthesis by a blocked mutant, strain 261, of Streptomyces fradiae. With 14C-labeled succinate or valine as an exogenous substrate, labeled protylonolide formation by high-NH4+ grown mycelia of strain 261 was lower than by low-NH4+ grown mycelia. When 14C-labeled palmitate or acetate + labeled propionate...

Rhodobacter sphaeroides only showed chemotaxis towards ammonia if grown under nitrogen-limited conditions. This chemotactic response was completely inhibited by the addition of methionine sulfoximine. There was no effect of methionine sulfoximine treatment on motility or taxis towards propionate, demonstrating that the effect is specific to ammonia taxis. It is known that methionine sulfoximine...

The electrochemical midpoint potentials (E(m)'s) of 13 cytochromes, in globin (c, c(2), c(551), c(553)), four-helix bundle (c', b(562)), alpha beta roll (b(5)), and beta sandwich (f) motifs, with E(m)'s spanning 450 mV were calculated with multiconformation continuum electrostatics (MCCE). MCCE calculates changes in oxidation free energy when a heme-axial ligand complex is moved from water into...

Sir: AR-5 (Mycinamicins) antibiotics, 16-membered ring macrolides, are produced by Micromonospora sp. These novel macrolides are potent antibiotics with unusual activity. Structures of these compounds were independently assigned by us and a group of Japanese workers.',') The assignments of the signals in the 13C NMR spectra have been previously reported". In analogy with the origin of the carbo...

Anaerobic digestion is now commonly used for sludge treatment. Most industrial digesters operate under mesophilic (37°C) or thermophilic (55°C) conditions. These two regimes are considered as optimal for methane production. In this work, continuous sludge digestion has been operated at labscale at 5 different temperatures comprised between 28° and 55°C. The reactors were first inoculated with a...

This study aimed to test the utility of the ozone challenge model for profiling novel compounds designed to reduce airway inflammation. The authors used a randomized, double-dummy, double-blind, placebo-controlled 3-period crossover design alternating single orally inhaled doses of fluticasone propionate (inhaled corticosteroids, 2 mg), oral prednisolone (oral corticosteroids, 50 mg), or matche...

Effects of amount of feed intake on in vivo remen propionate production and the reproducibility of measurements of propionate production rates were investigated in five dairy steers weighing 142 to 228 kg. Each steer received 275 g of an 80%-grain diet every 2 hours, and three of the five steers later received 500 g/2 hours. Rumen propionate pool sizes and production rates were determined at bo...

Studies were conducted to define steady state pH, propionic acid concentrations and fluid turnover in the rumen of steers fed every 3 h and to determine whether rates of ruminal propionic acid disappearance were linearly related to their in situ production rates. Ruminally fistulated beef steers (326 +/- 11 kg; n = 3) were fed eight times daily a 54% mixed hay: 46% corn-based concentrate diet t...

OBJECTIVE To assess the comparative efficacy of fluticasone propionate (FP) and montelukast (MON), using administrative claims for pediatric asthma in a clinical setting. STUDY DESIGN This retrospective observational study used the PharMetrics Integrated-Outcomes Database. Children age 4 to 17 years with an ICD-9-CM 493.xx for asthma, therapy with an inhaled corticosteroid in the 12 months be...