Search

With the increasing demand for alternative solutions to replace or optimize the use of synthetic fertilizers and pesticides, the inoculation of bacteria that can contribute to the growth and health of plants (PGPR) is essential. The properties classically sought in PGPR are the production of phytohormones and other growth-promoting molecules, and more rarely the production of exopolysaccharides. We compared the effect of two strains of exopolysaccharide-producing Rhizobium alamii on rapeseed grown in a calcareous silty-clay soil under water stress conditions or not. The effect of factors 'water stress' and 'inoculation' were evaluated on plant growth parameters and the diversity of microbiota associated to root and root-adhering soil compartments. Water stress resulted in a significant decrease in leaf area, shoot biomass and RAS/RT ratio (root-adhering soil/root tissues), as well as overall beta-diversity. Inoculation with R. alamii YAS34 and GBV030 under water-stress conditions produced the same shoot dry biomass compared to uninoculated treatment in absence of water stress, and both strains increased shoot biomass under water-stressed conditions (+7% and +15%, respectively). Only R. alamii GBV030 significantly increased shoot biomass under unstressed or water-stressed conditions compared to the non-inoculated control (+39% and +15%, respectively). Alpha-diversity of the root-associated microbiota after inoculation with R. alamii YAS34 was significantly reduced. Beta-diversity was significantly modified after inoculation with R. alamii GBV030 under unstressed conditions. LEfSe analysis identified characteristic bacterial families, Flavobacteriaceae and Comamonadaceae, in the RT and RAS compartments for the treatment inoculated by R. alamii GBV030 under unstressed conditions, as well as Halomonadaceae (RT) and several species belonging to Actinomycetales (RAS). We showed that R. alamii GBV030 had a PGPR effect on rapeseed growth, increasing its tolerance to water stress, probably involving its capacity to produce exopolysaccharides, and other plant growth-promoting (PGP) traits., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2021 The Authors. Published by Elsevier B.V. All rights reserved.)

Two novel anaerobic alkaliphilic strains, designated as LacT T and LacV T , were isolated from the Prony Bay Hydrothermal Field (PBHF, New Caledonia). Cells were motile, Gram-positive, terminal endospore-forming rods, displaying a straight to curved morphology during the exponential phase. Strains LacT T and LacV T were mesophilic (optimum 30°C), moderately alkaliphilic (optimum pH 8.2 and 8.7, respectively) and halotolerant (optimum 2% and 2.5% NaCl, respectively). Both strains were able to ferment yeast extract, peptone and casamino acids, but only strain LacT T could use sugars (glucose, maltose and sucrose). Both strains disproportionated crotonate into acetate and butyrate. Phylogenetic analysis revealed that strains LacT T and LacV T shared 96.4% 16S rRNA gene sequence identity and were most closely related to A. peptidifermentans Z-7036, A. namsaraevii X-07-2 and A. hydrothermalis FatMR1 (95.7%-96.3%). Their genome size was of 3.29Mb for strain LacT T and 3.06Mb for strain LacV T with a G+C content of 36.0 and 33.9mol%, respectively. The ANI value between both strains was 73.2 %. Finally, strains LacT T (=DSM 100337=JCM 30643) and LacV T (=DSM 100017=JCM 30644) are proposed as two novel species of the genus Alkaliphilus, order Clostridiales, phylum Firmicutes, Alkaliphilus serpentinus sp. nov. and Alkaliphilus pronyensis sp. nov., respectively. The genomes of the three Alkaliphilus species isolated from PBHF were consistently detected in the PBHF chimney metagenomes, although at very low abundance, but not significantly in the metagenomes of other serpentinizing systems (marine or terrestrial) worldwide, suggesting they represent indigenous members of the PBHF microbial ecosystem., (Copyright © 2021 Elsevier GmbH. All rights reserved.)

Acidithiobacillus ferrooxidans is a strict acidophilic chemolithoautotrophic bacterium that obtains its energy from reduced inorganic sulfur species or ferrous iron oxidation under aerobic conditions. Carbon felt electrodes were pre-colonized by A. ferrooxidansATCC 23270 T using ferrous iron or sulfur as electron donors, via the addition (or not) of a mixture of C14 acyl-homoserine lactones (C14-AHLs). Electrode coverage during pre-colonization was sparse regardless of the electron donor source, whereas activation of quorum sensing significantly enhanced it. Microbial fuel cells (MFCs) inoculated with pre-colonized electrodes (which behaved as biocathodes) were more efficient in terms of current production when iron was used as an electron donor. Biocathode coverage and current output were remarkably increased to -0.56 A m -2 by concomitantly using iron-based metabolism and C14-AHLs. Cyclic voltammetry displayed different electrochemical reactions in relation to the nature of the electron donor, underlying the implication of different electron transfer mechanisms., (© 2017 The Authors. Microbial Biotechnology published by John Wiley & Sons Ltd and Society for Applied Microbiology.)

Instead of requiring metal catalysts, MFCs utilize bacteria that oxidize organic matter and either transfer electrons to the anode or take electrons from the cathode. These devices are thus based on a wide microbial diversity that can convert a large array of organic matter components into sustainable and renewable energy. A wide variety of explored environments were found to host electrogenic bacteria, including extreme environments. In the present review, we describe how different ecosystems host electrogenic bacteria, as well as the physicochemical, electrochemical and biological parameters that control the currents from MFCs. We also report how using new molecular techniques allowed characterization of electrochemical biofilms and identification of potentially new electrogenic species. Finally we discuss these findings in the context of future research directions., (Copyright © 2015 Elsevier B.V. All rights reserved.)

Seventy-two newly readmitted, drug-free men with the diagnosis of schizophrenia by DSM-III were assigned randomly to receive fluphenazine hydrochloride at 5 mg, 10 mg, or 20 mg daily for 4 weeks. Fluphenazine (FLU), fluphenazine sulfoxide, 7-hydroxyfluphenazine, and fluphenazine N-oxide were measured by highly specific and sensitive radioimmunoassays. Data were analyzed by logistic regression using the Clinical Global Impressions Disabling Side Effects and Global Improvement as the outcome measures. Disabling side effects were defined as "side effects that significantly interfered with patient's functioning" or "side effects that outweigh therapeutic effects" (National Institute of Mental Health 1985, p. 839). Higher plasma FLU levels (up to 4.23 ng/mL) were significantly (p = .015) associated with a higher rate of global improvement. However, close to 90 percent of these acute patients had disabling side effects at a plasma FLU level of 2.7 ng/mL. At least in the patient's view, these disabling side effects negated or compromised the improvement in psychosis. Fluphenazine N-oxide may be a toxic metabolite in that it was more powerfully associated with side effects than was the parent FLU.

There is enormous variation in plasma levels of most neuroleptics in patients on the same dose. Much of the past research on the relation between plasma levels of antipsychotic drugs and clinical change, however, has been difficult to interpret. It does appear that decreased bioavailability, at least in public institutions, is rarely the cause of treatment failure. Aberrantly low plasma levels are more likely due to surreptitious noncompliance or drug interactions with enzyme inducers such as carbamazepine. Therapeutic plasma level ranges, in which good antipsychotic effect occurs without undue side effects, have been tentatively identified for perphenazine, haloperidol, fluphenazine, and chlorpromazine. The extent to which aberrantly high plasma levels are associated with inferior antipsychotic response is unclear. Antipsychotic plasma levels may be most useful when the distinction between side effects and worsening psychosis is unclear. The utility of high neuroleptic plasma levels in the treatment-resistant patient is unclear.