Proc Natl Acad Sci U S A
December 2024
Foraminifera are unicellular protists capable of precipitating calcite tests, which fossilize and preserve geochemical signatures of past environmental conditions dating back to the Cambrian period. The biomineralization mechanisms responsible for the mineral structures, which are key to interpreting palaeoceanographic signals, are poorly understood. Here, we present an extensive analysis of the test-bound proteins.
View Article and Find Full Text PDFThe excessive use of conventional medications to treat coccidiosis has led to concerns regarding drug residues in tissues and the emergence of multidrug resistance. Essential oils with anti-inflammatory and antioxidant activities may also have anticoccidial effects. The present study investigated the efficacy of D-limonene and its nanoemulsion form against Eimeria tenella in chickens.
View Article and Find Full Text PDFExoskeleton-aided active rehabilitation is a process that requires sensing and acting upon the motion intentions of the user. Typically, force sensors are used for this. However, they increase the weight and cost of these wearable devices.
View Article and Find Full Text PDFPhytoplankton in the ocean account for less than 1% of the global photosynthetic biomass, but contribute about 45% of the photosynthetically fixed carbon on Earth. This amazing production/biomass ratio implies a very high photosynthetic efficiency. But, how efficiently is the absorbed light used in marine photosynthesis? The introduction of picosecond and then femtosecond lasers for kinetic measurements in mid 1970s to 90 s was a revolution in basic photosynthesis research that vastly improved our understanding of the energy conversion processes in photosynthetic reactions.
View Article and Find Full Text PDFThis study investigated the anticoccidial activity of spinach () whole-plant extract against , both in vitro and in vivo. For this purpose, one hundred 8-day-old broiler chicks of both sexes were divided into four groups ( = 25 in each group). Chicks in the first group served as the negative control (non-treated-non-infected).
View Article and Find Full Text PDFThe core metabolic reactions of life drive electrons through a class of redox protein enzymes, the oxidoreductases. The energetics of electron flow is determined by the redox potentials of organic and inorganic cofactors as tuned by the protein environment. Understanding how protein structure affects oxidation-reduction energetics is crucial for studying metabolism, creating bioelectronic systems, and tracing the history of biological energy utilization on Earth.
View Article and Find Full Text PDFProc Natl Acad Sci U S A
July 2023
Of the six elements incorporated into the major polymers of life, phosphorus is the least abundant on a global scale [E. Anders, M. Ebihara, 46, 2363-2380 (1982)] and has been described as the "ultimate limiting nutrient" [T.
View Article and Find Full Text PDFUnlike most higher plants, unicellular algae can acclimate to changes in irradiance on time scales of hours to a few days. The process involves an enigmatic signaling pathway originating in the plastid that leads to coordinated changes in plastid and nuclear gene expression. To deepen our understanding of this process, we conducted functional studies to examine how the model diatom, acclimates to low light and sought to identify the molecules responsible for the phenomenon.
View Article and Find Full Text PDFAncestral metabolic processes involve the reversible oxidation of molecular hydrogen by hydrogenase. Extant hydrogenase enzymes are complex, comprising hundreds of amino acids and multiple cofactors. We designed a 13-amino acid nickel-binding peptide capable of robustly producing molecular hydrogen from protons under a wide variety of conditions.
View Article and Find Full Text PDFThe COVID-19 pandemic created the need for telerehabilitation development, while Industry 4.0 brought the key technology. As motor therapy often requires the physical support of a patient's motion, combining robot-aided workouts with remote control is a promising solution.
View Article and Find Full Text PDFOrig Life Evol Biosph
December 2022
Protein coordinated iron-sulfur clusters drive electron flow within metabolic pathways for organisms throughout the tree of life. It is not known how iron-sulfur clusters were first incorporated into proteins. Structural analogies to iron-sulfide minerals present on early Earth, suggest a connection in the evolution of both proteins and minerals.
View Article and Find Full Text PDFInfections caused by tetratrichomonas are commonly observed in geese. Most cases are subclinical, and the clinical form of the disease manifests itself with a greater mortality and the presence of caseous content in ceca. We describe the case of tetratrichomoniasis in a geese flock caused by , with the genetic analysis of the isolate being based on the fragments of 18SrRNA and ITS1-5.
View Article and Find Full Text PDFSulfur is an essential element of life that is assimilated by Earth's biosphere through the chemical breakdown of pyrite. On the early Earth, pyrite weathering by atmospheric oxygen was severely limited, and low marine sulfate concentrations persisted for much of the Archean eon. Here, we show an anoxic photochemical mechanism of pyrite weathering that could have provided substantial amounts of sulfate to the oceans as continents formed in the late Archean.
View Article and Find Full Text PDFThe rate of algal and cyanobacterial respiration in the light is an important ecophysiological term that remains to be completely characterized and quantified. To address this issue, we exploited process-specific decarboxylation rates from flux balance analysis and isotopically nonstationary metabolic flux analysis. Our study, based on published data, suggested that decarboxylation is about 22% of net CO2 assimilation when the tricarboxylic acid cycle is completely open (characterized by the commitment of alpha ketoglutarate to amino acid synthesis and very low rates of succinate formation).
View Article and Find Full Text PDFUnicellular photoautotrophs adapt to variations in light intensity by changing the abundance of light harvest pigment-protein complexes (LHCs) on time scales of hours to days. This process requires a feedback signal between the plastid (where light intensity is sensed) to the nucleus (where the genes for LHCs are encoded). The signals must include heretofore unidentified transcription factors that modify the expression level of the LHCs.
View Article and Find Full Text PDFThe redox state of the plastoquinone (PQ) pool is a known sensor for retrograde signaling. In this paper, we asked, "does the redox state of the PQ pool modulate the saturation state of thylakoid lipids?" Data from fatty acid composition and mRNA transcript abundance analyses suggest a strong connection between these two aspects in a model marine diatom. Fatty acid profiles of Phaeodactylum tricornutum exhibited specific changes when the redox state of the PQ pool was modulated by light and two chemical inhibitors [3-(3,4-dichlorophenyl)-1,1-dimethylurea (DCMU) or 2,5-dibromo-3-methyl-6-isopropyl-p-benzoquinone (DBMIB)].
View Article and Find Full Text PDFBenign prostatic hyperplasia, urolithiasis, recurrent urinary tract infections, and chronic prostatitis are diseases that are commonly diagnosed worldwide. Carotenoids, including lycopene, are widely available in fruits and vegetables, and it is postulated that they can be used in the prevention and treatment of benign urological conditions. The aim of this review is to familiarize doctors and their patients with the current knowledge on carotenoids and their conversion products in selected urological diseases.
View Article and Find Full Text PDFis a unicellular, anaerobic protozoan that has a low specificity for the hosts, and it could be a zoonosis. There are not many data about the occurrence of in bird species, and this study aimed to check the prevalence of infection in reproductive geese flocks. The result obtained showed that a parasite was present in 46.
View Article and Find Full Text PDFNon-fluidic array SPR imaging (SPRi) with appropriate biosensors is a new tool for the determination of various biomarkers in body fluids. Numerous biomarkers can be determined without signal enhancement or preliminarily preconcentration. The introduction of a new material solution of the chip may increase the scope of the application of this technique.
View Article and Find Full Text PDFBiological redox reactions drive planetary biogeochemical cycles. Using a novel, structure-guided sequence analysis of proteins, we explored the patterns of evolution of enzymes responsible for these reactions. Our analysis reveals that the folds that bind transition metal–containing ligands have similar structural geometry and amino acid sequences across the full diversity of proteins.
View Article and Find Full Text PDFThis work focuses on shear thickening fluids (STFs) as ceramic-polymer composites with outstanding protective properties. The investigation aims to determine the influence of raw material parameters on the functional properties of STFs. The following analyses were used to characterize both the raw materials and the STFs: scanning electron microscopy, dynamic light scattering, matrix-assisted laser desorption/ionization time-of-flight, chemical sorption analysis, rheological analysis, and kinetic energy dissipation tests.
View Article and Find Full Text PDFThe array SPR imaging (SPRi) technique is well suited to the determination of biomarkers in body fluids, called liquid biopsy. No signal enhancement or analyte preconcentration is required. With the aim of achieving signal enhancement and lowering the cost of a single determination, the replacement of gold-covered chips by silver-gold chips was investigated.
View Article and Find Full Text PDFComparative analysis of the sensitivity of two surface plasmon resonance (SPR) biosensors was conducted on a single-metallic Au sensor and bimetallic Ag-Au sensor, using a cathepsin S sensor as an example. Numerically modeled resonance curves of Au and Ag-Au layers, with parameters verified by the results of experimental reflectance measurement of real-life systems, were used for the analysis of these sensors. Mutual relationships were determined between ∂Y/∂n components of sensitivity of the Y signal in the SPR measurement to change the refractive index n of the near-surface sensing layer and ∂n/∂c sensitivity of refractive index n to change the analyte's concentration, c, for both types of sensors.
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