BrtB is an O-alkylating enzyme that generates fatty acid-bartoloside esters

Esterification reactions are central to many aspects of industrial and biological chemistry. The formation of carboxyesters typically occurs through nucleophilic attack of an alcohol onto the carboxylate carbon. Under certain conditions employed in organic synthesis, the carboxylate nucleophile can be alkylated to generate esters from alkyl halides, but this reaction has only been observed transiently in enzymatic chemistry. Here, we report a carboxylate alkylating enzyme – BrtB – that catalyzes O-C bond formation between free fatty acids of varying chain length and the secondary alkyl halide moieties found in the bartolosides. Guided by this reactivity, we uncovered a variety of natural fatty acid-bartoloside esters, previously unrecognized products of the bartoloside biosynthetic gene cluster. © 2020, The Author(s).We acknowledge funding by the European Research Council, through a Starting Grant (Grant Agreement 759840) to P.N.L., and by Fundação para a Ciência e Tecnologia (FCT) through project PTDC/BIA-BQM/29710/2017 and grant IF/01358/2014 to P.N.L. The work was also partially supported by Strategic Funding UIDB/04423/2020 and UIDP/04423/2020 by FCT and the European Regional Development Fund, as part of the program PT2020. We thank Emily Balskus (Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA, USA) for helpful discussions and Ralph Urbatzka (CIIMAR, University of Porto, Porto, Portugal) for help with cytotoxicity assays

Antiproliferative effects of the natural oxadiazine nocuolin A are associated with impairment of mitochondrial oxidative phosphorylation

Natural products are interesting sources for drug discovery. The natural product oxadiazine Nocuolin A (NocA) was previously isolated from the cyanobacterial strain Nodularia sp. LEGE 06071 and here we examined its cytotoxic effects against different strains of the colon cancer cell line HCT116 and the immortalized epithelial cell line hTERT RPE-1. NocA was cytotoxic against colon cancer cells and immortalized cells under conditions of exponential growth but was only weakly active against non-proliferating immortalized cells. NocA induced apoptosis by mechanism(s) resistant to overexpression of BCL family members. Interestingly, NocA affected viability and induced apoptosis of HCT116 cells grown as multicellular spheroids. Analysis of transcriptome profiles did not match signatures to any known compounds in CMap but indicated stress responses and induction of cell starvation. Evidence for autophagy was observed, and a decrease in various mitochondrial respiration parameter within 1h of treatment. These results are consistent with previous findings showing that nutritionally compromised cells in spheroids are sensitive to impairment of mitochondrial energy production due to limited metabolic plasticity. We conclude that the antiproliferative effects of NocA are associated with effects on mitochondrial oxidative phosphorylation.This research was supported by the Structured Program of R&D&I INNOVMAR - Innovation and Sustainability in the Management and Exploitation of Marine Resources (reference NORTE-01-0145-FEDER-000035, Research Line NOVELMAR), funded by the Northern Regional Operational Program (NORTE2020) through the European Regional Development Fund (ERDF). The project was additionally supported the project CYANCAN - Uncovering the cyanobacterial chemical diversity: the search for novel anticancer compounds (reference PTDC/MEDQUI/30944/2017) co-financed by NORTE 2020, Portugal 2020, and the European Union through the ERDF, and by Foundation for Science and Technology through national funds. RU was supported by the FCT postdoc grant SFRH/BPD/112287/2015 and MS by the FCT PhD grant SFRH/BD/108314/2015

The livestock roles in the wellbeing of rural communities of Timor-Leste

The livestock species play very important economic and socio-cultural roles for the wellbeing of rural households, such as food supply, source of income, asset saving, source of employment, soil fertility, livelihoods, transport, agricultural traction, agricultural diversification and sustainable agricultural production. The aim of this work was to identify and characterize the different roles that livestock and livestock species play in rural communities of Timor-Leste, highlighting the importance of animal production for the wellbeing and rural development, and relate the functions performed by livestock production with economic, social and cultural attributes of the communities. The data used in this study were collected in 2011 through a questionnaire survey in three rural communities in the district of Bobonaro, namely in a mountain area, an irrigation plain and a coastal zone, and were complemented with secondary data. Livestock production in Timor-Leste is predominantly familiar being chickens, pigs, goats, cattle, horses, buffaloes and sheep the main species. Beyond the economic function, each livestock species also performs social and cultural functions

Superhydrophobic structures on 316L stainless steel surfaces machined by nanosecond pulsed laser

In this paper nanosecond laser machining process was developed to improve the hydrophobicity of AISI 316L stainless steel surface. A geometrical model of laser machined Gaussian micro hole, together with constrain conditions, was established for the first time to predict surface contact angle and optimize structure geometries for maximizing its hydrophobicity. The effects of processing laser power and pitch of microstructures on the topography of the machined surface were investigated through laser machining experiment. Subsequently, the water droplet contact angle was measured to evaluate the hydrophobicity of different specimens. Results show that under the laser power of 10 W and 14 W, with the increase of the pitch of microstructures, the contact angle increases until it reaches its peak value then drops gradually. Under the large pitch of microstructure, the contact angle will increase with the increase of the processing laser power. Under the same pitch of microstructure, the contact angle will increase with the increase of ten-point height of surface topography, Sz which is a better parameter than Sa (arithmetical mean height) to characterise hydrophobicity of surface with Gaussian holes. This study shows that large Sz is an essential condition to form the stable and robust Cassie–Baxter state, i.e. a condition to achieve superhydrophobicity. The comparison between the predicted and measured contact angles in experiments shows that the proposed model can accurately predict contact angle and optimize the geometries of the microstructure to achieve maximum hydrophobicity

First record of anelosimus jucundus (O. Pickard-Cambridge, 1896) (araneae, theridiidae) in the state of Ceara, Brazil

We present the first record for Anelosimus jucundus O. Pickard-Cambridge, 1896 for the state of Ceará, Brazil. We collected 22 individuals in three different ecosystems: (1) Mangrove swamps, (2) Caatinga-type desert vegetation, and (3) Montane semi-deciduous tropical forest. We corrected the misinformation of Levi’s 1963 Ceará record, was actually from the state of Pernambuco. Anelosimus jucundus presents a wide altitudinal distribution, which indicates that this species can tolerate a variety climatic conditions and can colonize a variety of sites with different vegetation155933936CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO - CNPQCOORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL DE NÍVEL SUPERIOR - CAPESFUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPESPnão temnão temnão temThis study was financed in part by the Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - Brasil (CAPES), Finance Code 001 (G.A. Villanueva-Bonilla). We were also financially supported by the Instituto Na-cional de Ciência e Tecnologia dos Hymenoptera Para-sitoides (HYMPAR/Sudeste – CNPq/FAPESP/CAPES), FUNCAP-BPI proc. BP3- 00139- 00186.01.00/18 (research grants to J.F. Sobczak

Renal lesions in deer (Cervus elaphus) - Mycobacterium avium subsp. paratuberculosis involvelment

Renal lesions in deer (Cervus elaphus) - Mycobacterium avium subsp. paratuberculosis involvelment

Granulomatous lesions and Mycobacterium avium subsp. paratuberculosis in portuguese wild boars (Sus scrofa)

Granulomatous lesions and Mycobacterium avium subsp. paratuberculosis in portuguese wild boars (Sus scrofa)

Electrochemical studies on small electron transfer proteins using membrane electrodes

Journal of Electroanalytical Chemistry 541 (2003) 153-162Membrane electrodes (ME) were constructed using gold, glassy carbon and pyrolytic graphite supports and a dialysis membrane, and used to study the electrochemical behavior of small size electron transfer proteins: monohemic cytochrome c522 from Pseudomonas nautica and cytochrome c533 as well as rubredoxin from Desulfovibrio vulgaris . Different electrochemical techniques were used including cyclic voltammetry (CV), square wave voltammetry (SW) and differential pulse voltammetry (DP). A direct electrochemical response was obtained in all cases except with rubredoxin where a facilitator was added to the protein solution entrapped between the membrane and the electrode surface. Formal potentials and heterogeneous charge transfer rate constants were determined from the voltammetric data. The influence of the ionic strength and the pH of the medium on the electrochemical response at the ME were analyzed. The benefits from the use of the ME in protein electrochemistry and its role in modulating the redox behavior are analyzed. A critical comparison is presented with data obtained at non-MEs. Finally, the interactions that must be established between the proteins and the electrode surfaces are discussed, thereby modeling molecular interactions that occur in biological systems