The effect of trophic exposure to pyrolitic polycyclic aromatic hydrocarbons (PAH) on aerobic metabolism of zebrafish Danio rerio was investigated. There were no significant differences in standard metabolic rate (SMR), active metabolic rate (AMR) or aerobic metabolic scope (AS) at any sublethal concentration of PAH in the diet of adult or juvenile fish. This suggests that under these experimen...

BACKGROUND For economical bioethanol production from lignocellulosic materials, the major technical challenges to lower the production cost are as follows: (1) The microorganism should use efficiently all glucose and xylose in the lignocellulose hydrolysate. (2) The microorganism should have high tolerance to the inhibitors present in the lignocellulose hydrolysate. The aim of the present work ...

BACKGROUND Campylobacter jejuni is a leading cause of bacterial enteritis worldwide. This microaerophilic bacterium can survive in aerobic environments, suggesting it has protective mechanisms against oxidative stress. The clinical C. jejuni Bf strain is characterized by an increased resistance to oxygen. This study aimed to characterize the behavior of the clinical C. jejuni Bf strain under an...

Two granular sludge sequencing batch reactors (GSBR) with alternating anoxic/aerobic (R1) and anaerobic/aerobic (R2) conditions were operated with a 4-carbon-source synthetic influent. The physical properties of the granular sludge were very good (SVI ≈ 20 mL g−1) and high solid concentrations (up to 35 g L−1) were obtained in the bioreactor operated with a pre-anoxic phase with additional nitr...

Methicillin-resistant Staphylococcus aureus and vancomycin-resistant Enterococcus faecium were exposed to linezolid (MIC of 2 mg/liter) under aerobic or anaerobic conditions in an in vitro pharmacodynamic model. Drug concentration and half-life were adjusted to simulate clinical dosing (600 mg twice daily) of linezolid. Linezolid produced a 2-log(10) killing at 24 h, and rates of killing agains...

The anaerobic biodegradation of surfactants is used as an acceptability criterion in some environmental pieces of legislation (eco-label, risk assessment, etc.), without a proper evaluation of the relevance of such a characteristic. Available screening test methods to assess the anaerobic biodegradation do not simulate the real conditions prevailing in these anaerobic compartments but rather re...

For adaptation between anaerobic, micro-aerobic and aerobic conditions Escherichia coli's metabolism and in particular its electron transport chain (ETC) is highly regulated. Although it is known that the global transcriptional regulators FNR and ArcA are involved in oxygen response it is unclear how they interplay in the regulation of ETC enzymes under micro-aerobic chemostat conditions. Also,...

Pseudomonas aeruginosa has one A-type (caa3) and multiple C-type (cbb3) cytochrome c oxidases as well as two quinol oxidases for aerobic respiration. The caa3 oxidase is highly efficient in creating a proton gradient across the cell membrane, but it is not expressed under normal growth conditions and its physiological role has not been investigated. In the present study, a mutant strain deficie...

Continuous cultures of Pseudomonas aeruginosa (ATCC 9027) maintained at different dissolved oxygen concentrations (DO) were studied for the effects of DO on various culture properties, especially aerobic respiration and denitrification. The DO was varied from 0 mg/liter (completely anoxic conditions) to 1.3 mg/liter and measured with optical sensors that could accurately determine very low DO b...

Thirty six samples from each (aerobic and anoxic) activated sludge were collected from two wastewater treatment plants with MBRs in Berlin, Germany. The samples were prepared for count and definition of fungal isolates; these isolates were purified by conventional techniques and identified by microscopic examination. Sixty tow species belonging to 28 genera were isolated from activated sludge s...