Search results for "otos"

A New Niche for Anoxygenic Phototrophs as Endoliths

2018

ABSTRACT Anoxygenic phototrophic bacteria (APBs) occur in a wide range of aquatic habitats, from hot springs to freshwater lakes and intertidal microbial mats. Here, we report the discovery of a novel niche for APBs: endoliths within marine littoral carbonates. In a study of 40 locations around Isla de Mona, Puerto Rico, and Menorca, Spain, 16S rRNA high-throughput sequencing of endolithic community DNA revealed the presence of abundant phylotypes potentially belonging to well-known APB clades. An ad hoc phylogenetic classification of these sequences enabled us to refine the assignments more stringently. Even then, all locations contained such putative APBs, often reaching a significant pro…

Mg2+ homeostasis and transport in cyanobacteria – at the crossroads of bacterial and chloroplast Mg2+ import

2018

Abstract Magnesium cation (Mg2+) is the most abundant divalent cation in living cells, where it is required for various intracellular functions. In chloroplasts and cyanobacteria, established photosynthetic model systems, Mg2+ is the central ion in chlorophylls, and Mg2+ flux across the thylakoid membrane is required for counterbalancing the light-induced generation of a ΔpH across the thylakoid membrane. Yet, not much is known about Mg2+ homoeostasis, transport and distribution within cyanobacteria. However, Mg2+ transport across membranes has been studied in non-photosynthetic bacteria, and first observations and findings are reported for chloroplasts. Cyanobacterial cytoplasmic membranes…

Comparison of biocides, allelopathic substances and UV-C as treatments for biofilm proliferation on heritage monuments

2018

Abstract UV-C and biocide treatments are frequently used to treat historical monuments contaminated by autotrophic biofilms. In this study, the authors compare for the first time the efficacy of these treatments against microorganisms such as cyanobacteria and algae proliferating in the Vicherey church (Vicherey, Vosges Department, France). To identify the most environmentally friendly and also efficient method, an allelopathic treatment was also tested. Colorimetric and physiological measurements of treated biofilms were thus monitored for 6 months. Fungi growing on necrotic matter from treated biofilms were sampled and sequenced. With biocides, results showed incomplete eradication of bio…

Biodegradation of the aminopolyphosphonate DTPMP by the cyanobacteriumAnabaena variabilisproceeds via a C-P lyase-independent pathway

2017

Cyanobacteria, the only prokaryotes capable of oxygenic photosynthesis, play a major role in carbon, nitrogen and phosphorus global cycling. Under conditions of increased P availability and nutrient loading, some cyanobacteria are capable of blooming, rapidly multiplying and possibly altering the ecological structure of the ecosystem. Because of their ability of using non-conventional P sources, these microalgae can be used for bioremediation purposes. Under this perspective, the metabolization of the polyphosphonate diethylenetriaminepenta(methylenephosphonic) acid (DTPMP) by the strain CCALA 007 of Anabaena variabilis was investigated using 31 P NMR analysis. Results showed a quantitative…

2020

Globins are small heme-proteins that reversibly bind oxygen. Their most prominent roles in vertebrates are the transport and storage of O2 for oxidative energy metabolism, but recent research has suggested alternative, non-respiratory globin functions. In the species-rich and ecologically highly diverse taxon of arthropods, the copper-containing hemocyanin is considered the main respiratory protein. However, recent studies have suggested the presence of globin genes and their proteins in arthropod taxa, including model species like Drosophila. To systematically assess the taxonomic distribution, evolution and diversity of globins in arthropods, we systematically searched transcriptome and g…

Novel clinical findings in the first Egyptian case of Sotos syndrome caused by complete deletion of theNSD1gene

2017

Investigating mixotrophic metabolism in the model diatom Phaeodactylum tricornutum.

2017

Diatoms are prominent marine microalgae, interesting not only from an ecological point of view, but also for their possible use in biotechnology applications. They can be cultivated in phototrophic conditions, using sunlight as the sole energy source. Some diatoms, however, can also grow in a mixotrophic mode, wherein both light and external reduced carbon contribute to biomass accumulation. In this study, we investigated the consequences of mixotrophy on the growth and metabolism of the pennate diatom Phaeodactylum tricornutum , using glycerol as the source of reduced carbon. Transcriptomics, metabolomics, metabolic modelling and physiological data combine to indicate that glycerol affect…

Pyrrolo[3',2':6,7]cyclohepta[1,2-b]pyridines with potent photo-antiproliferative activity.

2017

Abstract Pyrrolo[3′,2′:6,7]cyclohepta[1,2-b]pyridines were synthesized as a new class of tricyclic system in which the pyridine ring is annelated to a cycloheptapyrrole scaffold, with the aim of obtaining new photosensitizing agents with improved antiproliferative activity and lower undesired toxic effects. A versatile synthetic pathway was approached, which allowed the isolation of derivatives of the title ring system with a good substitution pattern on the pyrrole moiety. Photobiological studies revealed that the majority of the new compounds showed a potent cytotoxic effect upon photoactivation with light of the proper wavelength, especially when decorated with a 2-ethoxycabonyl group an…

Apoptosis and apoptotic pathway in actinic prurigo by immunohistochemistry

2015

Background Actinic prurigo (AP) is an idiopathic photodermatosis, this entity requires exposure to UV-B and -A to develop lesions. Apoptosis is a physiological death program that can be initiated by a permanently active mechanism (extrinsic pathway) or irreparable damage (intrinsic pathway). Material and Methods Descriptive study, the sample size comprised 64 paraffin blocks of tissue with a diagnosis of AP. In H&E-stained slides, the diagnosis of AP was corroborated, and 1-µm-thick sections were processed for immunohistochemistry (IHC). A database was constructed with SPSS version 20, Inc., Chicago, IL, USA, and descriptive statistics were analyzed by X2 test and comparison of means. Resul…

Ultrafast structural changes within a photosynthetic reaction centre

2021

Nature <London> / Physical science 589, 310 - 314 (2021). doi:10.1038/s41586-020-3000-7