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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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At least 91 records · Page 5
All sourcesNASA NTRSDOE OSTI
NASA NTRS1987

Non-conventional approaches to food processing in CELSS, 1. Algal proteins: Characterization and process optimization

Protein isolate obtained from green algae cultivated under controlled conditions was characterized. Molecular weight determination of fractionated algal proteins using SDS-polyacrylamide gel electrophoresis revealed a wide spectrum of molecular weights ranging from 15,000 to 220,000. Isoelectric points of dissociated proteins were in the range of 3.95 to 6.20. Amino acid composition of protein isolate compared favorably with FAO standards. High content of essential amino acids leucine, valine, phenylalanine and lysine make algal protein isolate a high quality component of closed ecological life support system diets. To optimize the removal of algal lipids and pigments supercritical carbon dioxide extraction (with and without ethanol as a co-solvent) was used. Addition of ethanol to supercritical carbon dioxide resulted in more efficient removal of algal lipids and produced protein isolate with a good yield and protein recovery. The protein isolate extracted by the above mixture had an improved water solubility.

Nakhost, Z.↗
NASA NTRS1987

Non-conventional approaches to food processing in CELSS. I - Algal proteins: Characterization and process optimization

Protein isolate obtained from green algae (Scenedesmus obliquus) cultivated under controlled conditions was characterized. Molecular weight determination of fractionated algal proteins using SDS-polyacrylamide gel electrophoresis revealed a wide spectrum of molecular weights ranging from 15,000 to 220,000. Isoelectric points of dissociated proteins were in the range of 3.95 to 6.20. Amino acid composition of protein isolate compared favorably with FAO standards. High content of essential amino acids leucine, valine, phenylalanine and lysine makes algal protein isolate a high quality component of CELSS diets. To optimize the removal of algal lipids and pigments supercritical carbon dioxide extraction (with and without ethanol as a co-solvent) was used. Addition of ethanol to supercritical CO2 resulted in more efficient removal of algal lipids and produced protein isolate with a good yield and protein recovery. The protein isolate extracted by the above mixture had an improved water solubility.

Nakhost, Z.↗
NASA NTRS2000

Pollination and embryo development in Brassica rapa L. in microgravity

Plant reproduction under spaceflight conditions has been problematic in the past. In order to determine what aspect of reproductive development is affected by microgravity, we studied pollination and embryo development in Brassica rapa L. during 16 d in microgravity on the space shuttle (STS-87). Brassica is self-incompatible and requires mechanical transfer of pollen. Short-duration access to microgravity during parabolic flights on the KC-135A aircraft was used initially to confirm that equal numbers of pollen grains could be collected and transferred in the absence of gravity. Brassica was grown in the Plant Growth Facility flight hardware as follows. Three chambers each contained six plants that were 13 d old at launch. As these plants flowered, thin colored tape was used to indicate the date of hand pollination, resulting in silique populations aged 8-15 d postpollination at the end of the 16-d mission. The remaining three chambers contained dry seeds that germinated on orbit to produce 14-d-old plants just beginning to flower at the time of landing. Pollen produced by these plants had comparable viability (93%) with that produced in the 2-d-delayed ground control. Matched-age siliques yielded embryos of equivalent developmental stage in the spaceflight and ground control treatments. Carbohydrate and protein storage reserves in the embryos, assessed by cytochemical localization, were also comparable. In the spaceflight material, growth and development by embryos rescued from siliques 15 d after pollination lagged behind the ground controls by 12 d; however, in the subsequent generation, no differences between the two treatments were found. The results demonstrate that while no stage of reproductive development in Brassica is absolutely dependent upon gravity, lower embryo quality may result following development in microgravity.

short duration↗
NASA NTRS1997

Protein Crystal Movements and Fluid Flows During Microgravity Growth

The growth of protein crystals suitable for X-ray crystal structure analysis is an important topic. The methods of protein crystal growth are under increasing study whereby different methods are being compared via diagnostic monitoring including Charge Coupled Device (CCD) video and interferometry. The quality (perfection) of protein crystals is now being evaluated by mosaicity analysis (rocking curves) and X-ray topographic images as well as the diffraction resolution limit and overall data quality. Choice of a liquid-liquid linear crystal growth geometry and microgravity can yield a spatial stability of growing crystals and fluid, as seen in protein crystallization experiments on the unmanned platform EURICA. A review is given here of existing results and experience over several microgravity missions. The results include CCD video as well as interferometry during the mission, followed, on return to earth, by rocking curve experiments and full X-ray data collection on LMS and earth control lysozyme crystals. Diffraction data recorded from LMS and ground control apocrustacyanin C(sub 1) crystals are also described.

Boggon, Titus J.↗
NASA NTRS2009

Identifying and Inactivating Bacterial Spores

Problems associated with, and new strategies for, inactivating resistant organisms like Bacillus canaveralius (found at Kennedy Space Center during a survey of three NASA cleanrooms) have been defined. Identifying the particular component of the spore that allows its heightened resistance can guide the development of sterilization procedures that are targeted to the specific molecules responsible for resistance, while avoiding using unduly harsh methods that jeopardize equipment. The key element of spore resistance is a multilayered protein shell that encases the spore called the spore coat. The coat of the best-studied spore-forming microbe, B. subtilis, consists of at least 45 proteins, most of which are poorly characterized. Several protective roles for the coat are well characterized including resistance to desiccation, large toxic molecules, ortho-phthalaldehyde, and ultraviolet (UV) radiation. One important long-term specific goal is an improved sterilization procedure that will enable NASA to meet planetary protection requirements without a terminal heat sterilization step. This would support the implementation of planetary protection policies for life-detection missions. Typically, hospitals and government agencies use biological indicators to ensure the quality control of sterilization processes. The spores of B. canaveralius that are more resistant to osmotic stress would serve as a better biological indicator for potential survival than those in use currently.

Newcombe, David↗
NASA NTRS2016

Microarray Data Analysis of Space Grown Arabidopsis Leaves for Genes Important in Vascular Patterning

Venation patterning in leaves is a major determinant of photosynthesis efficiency because of its dependency on vascular transport of photoassimilates, water, and minerals. Arabidopsis thaliana grown in microgravity show delayed growth and leaf maturation. Gene expression data from the roots, hypocotyl, and leaves of A. thaliana grown during spaceflight vs. ground control analyzed by Affymetrix microarray are available through NASAs GeneLab (GLDS-7). We analyzed the data for differential expression of genes in leaves resulting from the effects of spaceflight on vascular patterning. Two genes were found by preliminary analysis to be upregulated during spaceflight that may be related to vascular formation. The genes are responsible for coding an ARGOS like protein (potentially affecting cell elongation in the leaves), and an F-boxkelch-repeat protein (possibly contributing to protoxylem specification). Further analysis that will focus on raw data quality assessment and a moderated t-test may further confirm upregulation of the two genes and/or identify other gene candidates. Plants defective in these genes will then be assessed for phenotype by the mapping and quantification of leaf vascular patterning by NASAs VESsel GENeration (VESGEN) software to model specific vascular differences of plants grown in spaceflight.

Weitzeal, A. J.↗
NASA NTRS2016

Microarray Data Analysis of Space Grown Arabidopsis Leaves for Genes Important in Vascular Patterning

Venation patterning in leaves is a major determinant of photosynthesis efficiency because of its dependency on vascular transport of photoassimilates, water, and minerals. Arabidopsis thaliana grown in microgravity show delayed growth and leaf maturation. Gene expression data from the roots, hypocotyl, and leaves of A. thaliana grown during spaceflight vs. ground control analyzed by Affymetrix microarray are available through NASA's GeneLab (GLDS-7). We analyzed the data for differential expression of genes in leaves resulting from the effects of spaceflight on vascular patterning. Two genes were found by preliminary analysis to be upregulated during spaceflight that may be related to vascular formation. The genes are responsible for coding an ARGOS like protein (potentially affecting cell elongation in the leaves), and an F-box/kelch-repeat protein (possibly contributing to protoxylem specification). Further analysis that will focus on raw data quality assessment and a moderated t-test may further confirm upregulation of the two genes and/or identify other gene candidates. Plants defective in these genes will then be assessed for phenotype by the mapping and quantification of leaf vascular patterning by NASA's VESsel GENeration (VESGEN) software to model specific vascular differences of plants grown in spaceflight.

Weitzeal, A. J.↗
DOE OSTI2023

Tetratricopeptide repeat protein SlREC2 positively regulates cold tolerance in tomato

Abstract Cold stress is a key environmental constraint that dramatically affects the growth, productivity, and quality of tomato (Solanum lycopersicum); however, the underlying molecular mechanisms of cold tolerance remain poorly understood. In this study, we identified REDUCED CHLOROPLAST COVERAGE 2 (SlREC2) encoding a tetratricopeptide repeat protein that positively regulates tomato cold tolerance. Disruption of SlREC2 largely reduced abscisic acid (ABA) levels, photoprotection, and the expression of C-REPEAT BINDING FACTOR (CBF)-pathway genes in tomato plants under cold stress. ABA deficiency in the notabilis (not) mutant, which carries a mutation in 9-CIS-EPOXYCAROTENOID DIOXYGENASE 1 (SlNCED1), strongly inhibited the cold tolerance of SlREC2-silenced plants and empty vector control plants and resulted in a similar phenotype. In addition, foliar application of ABA rescued the cold tolerance of SlREC2-silenced plants, which confirms that SlNCED1-mediated ABA accumulation is required for SlREC2-regulated cold tolerance. Strikingly, SlREC2 physically interacted with β-RING CAROTENE HYDROXYLASE 1b (SlBCH1b), a key regulatory enzyme in the xanthophyll cycle. Disruption of SlBCH1b severely impaired photoprotection, ABA accumulation, and CBF-pathway gene expression in tomato plants under cold stress. Taken together, this study reveals that SlREC2 interacts with SlBCH1b to enhance cold tolerance in tomato via integration of SlNCED1-mediated ABA accumulation, photoprotection, and the CBF-pathway, thus providing further genetic knowledge for breeding cold-resistant tomato varieties.

Zhang, Ying (ORCID:0000000169841164)↗
NASA NTRS2016

Microarray Data Analysis of Space Grown Arabidopsis Leaves for Genes Important in Vascular Patterning

Venation patterning in leaves is a major determinant of photosynthesis efficiency because of its dependency on vascular transport of photo-assimilates, water, and minerals. Arabidopsis thaliana grown in microgravity show delayed growth and leaf maturation. Gene expression data from the roots, hypocotyl, and leaves of A. thaliana grown during spaceflight vs. ground control analyzed by Affymetrix microarray are available through NASA's GeneLab (GLDS-7). We analyzed the data for differential expression of genes in leaves resulting from the effects of spaceflight on vascular patterning. Two genes were found by preliminary analysis to be up-regulated during spaceflight that may be related to vascular formation. The genes are responsible for coding an ARGOS (Auxin-Regulated Gene Involved in Organ Size)-like protein (potentially affecting cell elongation in the leaves), and an F-box/kelch-repeat protein (possibly contributing to protoxylem specification). Further analysis that will focus on raw data quality assessment and a moderated t-test may further confirm up-regulation of the two genes and/or identify other gene candidates. Plants defective in these genes will then be assessed for phenotype by the mapping and quantification of leaf vascular patterning by NASA's VESsel GENeration (VESGEN) software to model specific vascular differences of plants grown in spaceflight.

venation↗
DOE OSTI2026

F‐Box Protein‐Mediated Proteolytic Regulation of Phenylpropanoid Metabolism in Response to Biotic and Abiotic Stresses

Protein ubiquitination is a central regulatory mechanism governing plant growth, development and environmental adaptation. Ubiquitylomic studies have revealed that many enzymes in phenylpropanoid biosynthetic pathways are subject to ubiquitination. Increasing evidence indicates that specific F-box proteins target key enzymes in these pathways, including PAL, CCR, CAD, COMT and peroxidases in the lignin biosynthetic branch, and CHS in the flavonoid biosynthetic branch, thereby promoting their ubiquitination and selective degradation. These F-box proteins act in response to diverse developmental and environmental cues, including cellular carbon status, light quality and intensity, and biotic stresses (e.g., pathogen and insect attack). By regulating the stability and activity of both enzymes and regulatory proteins involved in phenylpropanoid biosynthesis, F-box proteins modulate the accumulation of simple phenolics and lignin polymers, ultimately contributing to plant resilience. This review summarizes recent advances in the characterization of F-box proteins involved in phenylpropanoid metabolism and their regulatory roles in response to biotic and abiotic stresses and identifies key knowledge gaps that limit mechanistic understanding of F-box protein-mediated proteolytic regulation of phenylpropanoid metabolism. In conclusion, insights into ubiquitin-mediated proteolytic control of phenylpropanoid metabolism offer promising avenues for enhancing bioactive phenolic production, advancing biofuel feedstock engineering and improving crop stress tolerance.

(A)biotic stress↗
NASA NTRS1990

Protein crystal growth in low gravity

The effect of low gravity on the growth of protein crystals and those parameters which will affect growth and crystal quality was studied. The proper design of the flight hardware and experimental protocols are highly dependent on understanding the factors which influence the nucleation and growth of crystals of biological macromolecules. Thus, those factors are investigated and the body of knowledge which has been built up for small molecule crystallization. These data also provide a basis of comparison for the results obtained from low-g experiments. The flows around growing crystals are detailed. The preliminary study of the growth of isocitrate lyase, the crystal morphologies found and the preliminary x ray results are discussed. The design of two apparatus for protein crystal growth by temperature control are presented along with preliminary results.

Feigelson, Robert S.↗
DOE OSTI2023

Acute stress reduces population-level metabolic and proteomic variation

Abstract Background Variation in omics data due to intrinsic biological stochasticity is often viewed as a challenging and undesirable feature of complex systems analyses. In fact, numerous statistical methods are utilized to minimize the variation among biological replicates. Results We demonstrate that the common statistics relative standard deviation (RSD) and coefficient of variation (CV), which are often used for quality control or part of a larger pipeline in omics analyses, can also be used as a metric of a physiological stress response. Using an approach we term Replicate Variation Analysis (RVA), we demonstrate that acute physiological stress leads to feature-wide canalization of CV profiles of metabolomes and proteomes across biological replicates. Canalization is the repression of variation between replicates, which increases phenotypic similarity. Multiple in-house mass spectrometry omics datasets in addition to publicly available data were analyzed to assess changes in CV profiles in plants, animals, and microorganisms. In addition, proteomics data sets were evaluated utilizing RVA to identify functionality of reduced CV proteins. Conclusions RVA provides a foundation for understanding omics level shifts that occur in response to cellular stress. This approach to data analysis helps characterize stress response and recovery, and could be deployed to detect populations under stress, monitor health status, and conduct environmental monitoring.

59 BASIC BIOLOGICAL SCIENCES↗
NASA NTRS1996

A Fiber Optic Probe for Monitoring Protein Aggregation, Nucleation, and Crystallization

Protein crystals are experimentally grown in hanging drops in microgravity experiments on-board the Space Shuttle orbiter. The technique of dynamic light scattering (DLS) can be used to monitor crystal growth process in hanging droplets (approx. 30 (L)) in microgravity experiments, but elaborate instrumentation and optical alignment problems have made in-situ applications difficult. In this paper we demonstrate that such experiments are now feasible. We apply a newly developed fiber optic probe to various earth and space (micro- gravity) bound protein crystallization system configurations to test its capability. These include conventional batch (cuvette or capillary) systems, hanging drop method in a six-pack hanging drop vapor diffusion apparatus (HDVDA), a modified HDVDA for temperature- induced nucleation and aggregation studies, and a newly envisioned dynamically controlled vapor diffusion system (DCVDS) configuration. Our compact system exploits the principles of DLS and offers a fast (within a few seconds) means of quantitatively and non-invasively monitoring the various growth stages of protein crystallization. In addition to DLS capability, the probe can also be used for performing single-angle static light scattering measurements. It utilizes extremely low levels of laser power (approx. few (W)) without a need of having any optical alignment and vibration isolation. The compact probe is also equipped with a miniaturized microscope for visualization of macroscopic protein crystals. This new optical diagnostic system opens up enormous opportunity for exploring new ways to grow good quality crystals suitable for x-ray crystallographic analysis and may help develop a concrete scientific basis for understanding the process of crystallization.

Ansari, Rafat R.↗
DOE OSTI2021

Assessment of TMT Labeling Efficiency in Large-Scale Quantitative Proteomics: The Critical Effect of Sample pH

Isobaric labeling via tandem mass tag (TMT) reagents enables sample multiplexing prior to LC–MS/MS, facilitating high-throughput large-scale quantitative proteomics. Consistent and efficient labeling reactions are essential to achieve robust quantification; therefore, embedded in our clinical proteomic protocol is a quality control (QC) sample that contains a small aliquot from each sample within a TMT set, referred to as “Mixing QC.” This Mixing QC enables the detection of TMT labeling issues by LC–MS/MS before combining the full samples to allow for salvaging of poor TMT labeling reactions. While TMT labeling is a valuable tool, factors leading to poor reactions are not fully studied. We observed that relabeling does not necessarily rescue TMT reactions and that peptide samples sometimes remained acidic after resuspending in 50 mM HEPES buffer (pH 8.5), which coincided with low labeling efficiency (LE) and relatively low median reporter ion intensities (MRIIs). To obtain a more resilient TMT labeling procedure, we investigated LE, reporter ion missingness, the ratio of mean TMT set MRII to individual channel MRII, and the distribution of log 2 reporter ion ratios of Mixing QC samples. We discovered that sample pH is a critical factor in LE, and increasing the buffer concentration in poorly labeled samples before relabeling resulted in the successful rescue of TMT labeling reactions. Moreover, resuspending peptides in 500 mM HEPES buffer for TMT labeling resulted in consistently higher LE and lower missing data. By better controlling the sample pH for labeling and implementing multiple methods for assessing labeling quality before combining samples, we demonstrate that robust TMT labeling for large-scale quantitative studies is achievable.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2023

Kinetic Growth of Multicomponent Microcompartment Shells

An important goal of systems and synthetic biology is to produce high value chemical species in large quantities. Microcompartments, which are protein nanoshells encapsulating catalytic enzyme cargo, could potentially function as tunable nanobioreactors inside and outside cells to generate these high value species. Modifying the morphology of microcompartments through genetic engineering of shell proteins is one viable strategy to tune cofactor and metabolite access to encapsulated enzymes. However, this is a difficult task without understanding how changing interactions between the many different types of shell proteins and enzymes affect microcompartment assembly and shape. Here, we use multiscale molecular dynamics and experimental data to describe assembly pathways available to microcompartments composed of multiple types of shell proteins with varied interactions. As the average interaction between the enzyme cargo and the multiple types of shell proteins is weakened, the shell assembly pathway transitions from (i) nucleating on the enzyme cargo to (ii) nucleating in the bulk and then binding the cargo as it grows to (iii) an empty shell. Atomistic simulations and experiments using the 1,2-propanediol utilization microcompartment system demonstrate that shell protein interactions are highly varied and consistent with our multicomponent, coarse-grained model. Furthermore, our results suggest that intrinsic bending angles control the size of these microcompartments. Altogether, our simulations and experiments provide guidance to control microcomparmtent size and assembly by modulating the interactions between shell proteins.

defects↗
DOE OSTI2021

Supplemental dietary full-fatted and defatted Desmodesmus sp. exerted similar effects on growth performance, gut health, and excreta hydrothermal liquefaction of broiler chicks

This study determined effects of full-fatted (C046, 41% crude protein) and lipid extracted (LEA, 39% crude protein) microalgae Desmodesmus sp. on growth performance, gut health, and excreta hydrothermal liquefaction of broiler chickens. Two experiments were conducted by feeding day-old Cornish male chicks: 1) a corn-soybean meal basal diet (control) 2) control +5% C046, or 3) control +5% LEA for 2 weeks. Growth performance was measured weekly in both experiments. Blood, liver, and duodenum samples of chickens were collected for biochemical analyses, and excreta samples were collected for hydrothermal liquefaction (300 °C, 60 min) at the end of Experiment 2. Compared with the control, supplemental dietary C046 and LEA enhanced average daily gain (13% to 40%, p < 0.05) in both experiments, and improved feed efficiency (15% and 11%, p < 0.01) in Experiment 2. The C046 and LEA diets enhanced the duodenum (19% to –2 fold, p < 0.05), but decreased the liver (17 to 78%, p < 0.05) mRNA abundances of interleukins-1, 6 and 8 and (or) tumor necrosis factor-α, respectively, compared with the controls. Meanwhile, the two types of biomass enhanced the protein amounts of claudin-1 in the duodenum (5–34%, p < 0.05) than the controls. Hydrothermal liquefaction of the excreta derived from the three diets showed no major differences in total bio-crude oil (average of 23%), hydrochar yield (average of 12%), or elemental compositions. However, the heating values of the resultant two bio-crude oils from the microalgae-fed chicken excreta (average of 34 MJ/kg) were 16% greater than those from the control chickens (29 MJ/kg). In conclusion, supplementing the full- and de-fatted Desmodesmus sp. microalgal biomass in the starter diets for broiler chickens produced largely similar improvements of growth performance, gut health, and excreta-derived oil quality.

09 BIOMASS FUELS↗
NASA NTRS1990

Algae for controlled ecological life support system diet characterization of cyanobacteria 'spirulina' in batch cultures

Spirulina sp. is a bioregenerative photosynthetic and edible alga for space craft crews in a Closed Ecological Life Support System (CLESS). It was characterized for growth rate and biomass yield in batch cultures, under various environmental conditions. The cell characteristics were identified for one strain of Spirulina: S. maxima. Fast growth rate and high yield were obtained. The partitioning of the assimulatory products (proteins, carbohydrates, lipids) were manipulated by varying the environmental conditions. Experiments with Spirulina demonstrated that under stress conditions carbohydrate increased at the expense of protein. In other experiments, where the growth media were sufficient in nutrients and incubated under optimum growth conditions, the total proteins were increased up to almost 70 percent of the organic weight. In other words, the nutritional quality of the alga could be manipulated by growth conditions. These results support the feasibility of considering Spirulina as a subsystem in CELSS because of the ease with which its nutrient content can be manipulated.

Tadros, M. G.↗
DOE OSTI2025

Tumor-promoting UBR4 coordinates impaired mitophagy–associated senescence and lung adenocarcinoma pathogenesis

Cellular senescence, an irreversible cell cycle arrest, plays a pivotal role in development, aging, and tumor suppression. However, the fundamental pathway coordinating senescence and neoplastic transformation remains unclear. Here, we describe the tumorigenic involvement of ubiquitin protein ligase E3 component n-recognin 4 (UBR4), an E3 ubiquitin ligase of the N-degron pathway, in lung adenocarcinoma (LUAD). Public genome databases revealed high UBR4 expression in LUAD patients, associated with a dysregulated cell cycle and impaired mitochondrial homeostasis.UBR4knockout (ΔUBR4) in A549 lung cancer cells induced cellular senescence with defective mitochondria. Restoration of UBR4 or antioxidant treatment reversed the ΔUBR4 phenotypes caused by impaired mitophagy. Mitochondrial stress exacerbated mitochondrial dysfunction in ΔUBR4 cells, contributing to diverse cellular phenotypes. Additionally, ΔUBR4 cells exhibited substantially slow tumor growth in mouse xenograft models. In LUAD patients, UBR4 levels correlated with tumor stage, mitophagy markers, and poor survival. These findings suggest a tumor-promoting function of UBR4 in LUAD by regulating mitochondrial quality control. Further research into the pharmacological inhibition of UBR4 could open promising avenues for developing effective antitumor therapies targeting LUAD.

Science & Technology - Other Topics↗