Search results for "catechol"

Availability of O 2 as a Substrate in the Cytoplasm of Bacteria under Aerobic and Microaerobic Conditions

1998

ABSTRACT The growth rates of Pseudomonas putida KT2442 and mt-2 on benzoate, 4-hydroxybenzoate, or 4-methylbenzoate showed an exponential decrease with decreasing oxygen tensions (partial O 2 tension [pO 2 ] values). The oxygen tensions resulting in half-maximal growth rates were in the range of 7 to 8 mbar of O 2 (corresponding to 7 to 8 μM O 2 ) (1 bar = 10 5 Pa) for aromatic compounds, compared to 1 to 2 mbar for nonaromatic compounds like glucose or succinate. The decrease in the growth rates coincided with excretion of catechol or protocatechuate, suggesting that the activity of the corresponding oxygenases became limiting. The experiments directly establish that under aerobic and micr…

Molecular analysis of the catechol-degrading bacterial community in a coal wasteland heavily contaminated with PAHs

2010

International audience; A PCR-based molecular tool was developed to estimate the diversity of the catechol-degrading bacterial community in a coal wasteland heavily contaminated with PAHS. A degenerate primer pair specific to catA sequences was designed by multiple alignment of known sequences coding a key intermediate of the β-ketoadiapate pathway degrading catechol, namely catechol 1,2-dioxygenase. The specificity of this primer pair was assessed in 21 pure strains by PCR and sequencing. Comparison of the 16S rDNA and catA phylogenies revealed an absence of congruence between these two genes. The primer set was able to amplify catA sequences in DNA extracts from an industrial soil highly …

From the Golgi-Cajal mapping to the transmitter-based characterization of the neuronal networks leading to two modes of brain communication: Wiring a…

2007

After Golgi-Cajal mapped neural circuits, the discovery and mapping of the central monoamine neurons opened up for a new understanding of interneuronal communication by indicating that another form of communication exists. For instance, it was found that dopamine may be released as a prolactin inhibitory factor from the median eminence, indicating an alternative mode of dopamine communication in the brain. Subsequently, the analysis of the locus coeruleus noradrenaline neurons demonstrated a novel type of lower brainstem neuron that monosynaptically and globally innervated the entire CNS. Furthermore, the ascending raphe serotonin neuron systems were found to globally innervate the forebrai…

Is activated hemocyanin instead of phenoloxidase involved in immune response in woodlice?

2008

In the Common woodlouse Porcellio scaber (Crustacea: Isopoda: Oniscidea), experimental immune challenge did not induce the expression of pro-phenoloxidase that, in most other invertebrates studied thus far, can be activated into phenoloxidase via an activation cascade upon immune challenge. Instead, Porcellio hemocyanin proved to exhibit catecholoxidase activity upon activation. However, none of the activating factors known from other invertebrates other than SDS-treatment resulted in activation of hemocyanin into a functional phenoloxidase in vitro. The distinct characteristics of isopod hemocyanin are reflected by the quaternary structure of the hemocyanin dodecamers that differs from tha…

Modulation of immune responses of Rhynchophorus ferrugineus (Insecta: Coleoptera) induced by the entomopathogenic nematode Steinernema carpocapsae (N…

2014

Aim of this study was to investigate relationships between the red palm weevil (RPW) Rhynchophorus ferrugineus (Olivier) and the entomopathogenic nematode Steinernema carpocapsae (EPN); particularly, the work was focused on the immune response of the insect host in naive larvae and after infection with the EPN. Two main immunological processes have been addressed: the activity and modulation of host prophenoloxidase-phenoloxidase (proPO) system, involved in melanization of not-self and hemocytes recognition processes responsible for not-self encapsulation. Moreover, immune depressive and immune evasive strategies of the parasite have been investigated. Our results suggest that RPW possess a…

Studies on pathways of ring opening of benzene in a Fenton system

1995

Ring-opened products of benzene metabolism have been postulated to play a role in hematotoxicity and leukemogenesis. The reaction of benzene in the Fenton system was reexamined to determine the presence of compounds which might serve as intermediates in the formation of trans, trans-muconaldehyde (MUC), a microsomal hematotoxic metabolite of benzene. Benzene dihydrodiol (DHD) was found in this system based on coelution with authentic standard, ultraviolet (UV) absorption characteristics, and molecular weight. Incubation of DHD in the Fenton system resulted in the formation of phenol (PH), catechol (CAT), and products which reacted with thiobarbituric acid to form chromogens absorbing at 495…

G protein biased signaling by non-catechol dopamine D1 receptor agonists

2020

Dopamine is a catecholamine neurotransmitter with essential roles in voluntary movement, working memory, attention, and reward. Dopamine acts through five G protein coupled receptors with the D1 and D5 receptors (D1R) stimulating Galphas/olf activation and increasing neuronal excitability. Deficits in D1R signaling are implicated in Parkinson’s disease motor deficits as well as cognitive deficits in schizophrenia and attention deficit hyperactivity disorder. For more than 40 years, academic and industry scientists have been searching for a drug-like D1R agonist, but this has remained elusive. The challenge in developing D1R selective agonists is that all previous agonists possess a common p…

Correspondence to Sand et al. “Critical Reappraisal of a Catechol-O-Methyltransferase Transversion Variant in Schizophrenia”

2010

A New Mutation in the Ryanodine Receptor 2 Gene (RYR2 C2277R) as a Cause Catecholaminergic Polymorphic Ventricular Tachycardia

2015

Effects of waterborne iron overload and simulated winter conditions on acute physiological stress response of whitefish, Coregonus lavaretus

2003

Two-year-old whitefish (Coregonus lavaretus) were exposed for 30 days to episodic iron overload in iron-rich humic water (5%) supplemented with inorganic iron (5 mg FeL(-1)). Two parallel laboratory exposures were performed, one under conditions simulating winter and the other under conditions simulating spring. After exposure, some of the fish were subjected to acute handling stress in the form of a short air challenge to reveal possible modification of the primary and secondary stress responses. In whitefish sampled without additional handling, iron accumulated in the liver (under spring conditions) and gills (under winter and spring conditions); plasma catecholamine and beta-estradiol (b…