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Burke posted an update 8 months, 3 weeks ago
While scientific uncertainty always invites the risk of politicization and raises questions of how to communicate about science, this risk is magnified for COVID-19. The limited data and accelerated research timelines mean that some prominent models or findings inevitably will be overturned or retracted. In this research, we examine the attitudes of more than 6000 Americans across five different survey experiments to understand how the cue giver and cue given about scientific uncertainty regarding COVID-19 affect public trust in science and support for science-based policy. Criticism from Democratic political elites undermines trust more than criticism from Republicans. Emphasizing uncertainty in projections can erode public trust in some contexts. Downplaying uncertainty can raise support in the short term, but reversals in projections may temper these effects or even reduce scientific trust. Careful science communication is critical to maintaining public support for science-based policies as the scientific consensus shifts over time.Enzymatic processing of fish by-products for recovery of peptides (hydrolysates) is a promising technology to reach food grade ingredients of high nutritional quality. Despite this, their bitter taste and “fish” odor block implementation in food products and limit their economic potential. Trimethylamine (TMA) is a known contributor to malodor in fish. Current strategies to mask or remove the odor either are not effective or give rise to undesirable side effects. As an alternative approach to remediate TMA, we propose a novel enzymatic strategy to convert TMA into the odorless trimethylamine N-oxide (TMAO) using TMA monooxygenases (Tmms). We identified a diverse set of bacterial Tmms using a sequence similarity network. Purified, recombinant enzymes were assessed for their biocatalytic capacity by monitoring NADPH consumption and TMAO generation. Selected Tmms were subjected to biochemical characterization and investigated for their ability to oxidize TMA in an industry-relevant substrate. From the 45 bacterility of marine protein hydrolysates. Following a systematic investigation of 45 putative bacterial trimethylamine monooxygenases from several phyla, we expand the repertoire of known active trimethylamine monooxygenases. As a proof-of-concept, we demonstrate that three of these enzymes oxidized trimethylamine in an industry-relevant salmon protein hydrolysate. Our results add new oxidoreductases to the industrial biocatalytic toolbox and provide a new point of departure for enzyme process developments in marine biorefineries.Nonribosomal peptides (NRPs) are a class of secondary metabolites usually produced by microorganisms. They are of paramount importance in different applications, including biocontrol and pharmacy. Brevibacillus spp. are a rich source of NRPs yet have received little attention. In this study, we characterize four novel bogorol variants (bogorols I to L, cationic linear lipopeptides) and four succilins (succilins I to L, containing a succinyl group that is attached to the Orn3/Lys3 in bogorols I to L) from the biocontrol strain Brevibacillus laterosporus MG64. Further investigation revealed that the bogorol family of peptides employs an adenylation pathway for lipoinitiation, different from the usual pattern, which is based on an external ligase and coenzyme A. Moreover, the formation of valinol was proven to be mediated by a terminal reductase domain and a reductase encoded by the bogI gene. Furthermore, succinylation, which is a novel type of modification in the family of bogorols, was discovered. Its occurreated lipoinitiation of bogorols represents a novel pathway by which NRPs incorporate fatty acid tails. This pathway provides the possibility to engineer the lipid tail of NRPs without identifying a fatty acid coenzyme ligase, which is usually not present in the biosynthetic gene cluster. The terminal reductase domain (TD) and BogI-mediated valinol formation and their effect on the biological activity of bogorols are revealed. Succinylation, which is rarely reported in NRPs, was discovered in the bogorol family of peptides. We demonstrate that bogorols combat bacterial pathogens by forming pores in the cell membrane. We also report the synergistic effect of two natural products (relacidine B and bogorol K) produced by the same strain, which is relevant for competition for a niche.Clostridium thermocellum and Thermoanaerobacterium saccharolyticum were grown in cellobiose-limited chemostat cultures at a fixed dilution rate. C. thermocellum produced acetate, ethanol, formate, and lactate. Surprisingly, and in contrast to batch cultures, in cellobiose-limited chemostat cultures of T. saccharolyticum, ethanol was the main fermentation product. Enzyme assays confirmed that in C. thermocellum, glycolysis proceeds via pyrophosphate (PPi)-dependent phosphofructokinase (PFK), pyruvate-phosphate dikinase (PPDK), as well as a malate shunt for the conversion of phosphoenolpyruvate (PEP) to pyruvate. Pyruvate kinase activity was not detectable. MK4827 In T. saccharolyticum, ATP but not PPi served as cofactor for the PFK reaction. High activities of both pyruvate kinase and PPDK were present, whereas the activities of a malate shunt enzymes were low in T. saccharolyticum In C. thermocellum, glycolysis via PPi-PFK and PPDK obeys the equation glucose + 5 NDP + 3 PPi → 2 pyruvate + 5 NTP + Pi (where NDP is nuharging of tRNA with amino acids may become more reversible. This may contribute to the observed excretion of amino acids during sugar fermentation by Clostridium thermocellum and Thermoanaerobacterium saccharolyticum Calculation of the energetic advantage of reversible pyrophosphate-dependent glycolysis, as occurs in Clostridium thermocellum, could not be properly evaluated, as currently available genome-scale models neglect the anabolic generation of pyrophosphate in, for example, polymerization of amino acids to protein. This anabolic pyrophosphate replaces ATP and thus saves energy. Its amount is, however, too small to cover the pyrophosphate requirement of sugar catabolism in glycolysis. Consequently, pyrophosphate for catabolism is generated according to ATP + Pi → ADP + PPi.