Metabolic Efficiency Research Articles

Quorum-sensing agr system of Staphylococcus aureus primes gene expression for protection from lethal oxidative stress

The agr quorum-sensing system links Staphylococcus aureus metabolism to virulence, in part by increasing bacterial survival during exposure to lethal concentrations of H2O2, a crucial host defense against S. aureus. We now report that protection by agr surprisingly extends beyond post-exponential growth to the exit from stationary phase when the agr system is no longer turned on. Thus, agr can be considered a constitutive protective factor. Deletion of agr resulted in decreased ATP levels and growth, despite increased rates of respiration or fermentation at appropriate oxygen tensions, suggesting that Δagr cells undergo a shift towards a hyperactive metabolic state in response to diminished metabolic efficiency. As expected from increased respiratory gene expression, reactive oxygen species (ROS) accumulated more in the agr mutant than in wild-type cells, thereby explaining elevated susceptibility of Δagr strains to lethal H2O2 doses. Increased survival of wild-type agr cells during H2O2 exposure required sodA, which detoxifies superoxide. Additionally, pretreatment of S. aureus with respiration-reducing menadione protected Δagr cells from killing by H2O2. Thus, genetic deletion and pharmacologic experiments indicate that agr helps control endogenous ROS, thereby providing resilience against exogenous ROS. The long-lived ‘memory’ of agr-mediated protection, which is uncoupled from agr activation kinetics, increased hematogenous dissemination to certain tissues during sepsis in ROS-producing, wild-type mice but not ROS-deficient (Cybb−/−) mice. These results demonstrate the importance of protection that anticipates impending ROS-mediated immune attack. The ubiquity of quorum sensing suggests that it protects many bacterial species from oxidative damage.

Quorum-sensing agr system of Staphylococcus aureus primes gene expression for protection from lethal oxidative stress.

The agr quorum-sensing system links Staphylococcus aureus metabolism to virulence, in part by increasing bacterial survival during exposure to lethal concentrations of H2O2, a crucial host defense against S. aureus. We now report that protection by agr surprisingly extends beyond post-exponential growth to the exit from stationary phase when the agr system is no longer turned on. Thus, agr can be considered a constitutive protective factor. Deletion of agr resulted in decreased ATP levels and growth, despite increased rates of respiration or fermentation at appropriate oxygen tensions, suggesting that Δagr cells undergo a shift towards a hyperactive metabolic state in response to diminished metabolic efficiency. As expected from increased respiratory gene expression, reactive oxygen species (ROS) accumulated more in the agr mutant than in wild-type cells, thereby explaining elevated susceptibility of Δagr strains to lethal H2O2 doses. Increased survival of wild-type agr cells during H2O2 exposure required sodA, which detoxifies superoxide. Additionally, pretreatment of S. aureus with respiration-reducing menadione protected Δagr cells from killing by H2O2. Thus, genetic deletion and pharmacologic experiments indicate that agr helps control endogenous ROS, thereby providing resilience against exogenous ROS. The long-lived 'memory' of agr-mediated protection, which is uncoupled from agr activation kinetics, increased hematogenous dissemination to certain tissues during sepsis in ROS-producing, wild-type mice but not ROS-deficient (Cybb-/-) mice. These results demonstrate the importance of protection that anticipates impending ROS-mediated immune attack. The ubiquity of quorum sensing suggests that it protects many bacterial species from oxidative damage.

Understanding stoichiometric constraints on growth using resource use efficiency imbalances

Growth is a function of the net accrual of resources by an organism. Energy and elemental contents of organisms are dynamically linked through their uptake and allocation to biomass production, yet we lack a full understanding of how these dynamics regulate growth rate. Here, we develop a multivariate imbalance framework, the growth efficiency hypothesis, linking organismal resource contents to growth and metabolic use efficiencies, and demonstrate its effectiveness in predicting consumer growth rates under elemental and food quantity limitation. The relative proportions of carbon (%C), nitrogen (%N), phosphorus (%P), and adenosine triphosphate (%ATP) in consumers differed markedly across resource limitation treatments. Differences in their resource composition were linked to systematic changes in stoichiometric use efficiencies, which served to maintain relatively consistent relationships between elemental and ATP content in consumer tissues and optimize biomass production. Overall, these adjustments were quantitatively linked to growth, enabling highly accurate predictions of consumer growth rates.

Effect of Milk-Feeding Frequency and Calcium Gluconate Supplementation on Growth, Health, and Reproductive and Metabolic Features of Holstein Heifers at a Rearing Farm.

We compared the effects of milk-feeding in 288 Holstein calves (72 per group) which were fed twice (2F) or thrice (3F) daily, with or without the addition of hydrogenated fat-embedded calcium gluconate (G) supplemented in the starter food and in the daily diet up to the age of 9 months, on the calves' metabolism, growth, health, and reproductive efficiency up to first pregnancy. The calves received 6 L of milk replacer (130 g/L) and had ad libitum access to water and textured calf starter with or without gluconate. Gluconate supplementation promoted a "catch-up" in growth in supplemented calves compared to their counterparts that did not receive gluconate. Gluconate appeared to reduce animal metabolic stress during key events, such as weaning and transfer into open-door pens, reducing fructosamine (352.61 vs. 303.06 in 3FG and 3F, respectively; p = 0.028) and urea (3F revealed the highest values compared with the other three groups: 19.06 for 3F vs. 13.9 (2F), 13.7 (2FG), and 14.3 (3FG), respectively, p = 0.002) from weaning onwards. The feeding of dairy calves with milk replacer three rather than two times per day tended to be associated with better health from weaning to 4 months old; parameters such as ultrasound lung score and calf health score improved over time (p < 0.001). Thrice-daily feeding with milk replacer tended to reduce the number of artificial inseminations per pregnancy in heifers by 0.2 points (p = 0.092). We confirmed significant correlations between early health and growth parameters and reproductive efficiency and a positive correlation between body weight and average daily weight gain and the thickness of the back fat layer in young heifers (r = 0.245; p < 0.0001; r = 0.214; p < 0.0001 respectively). Our study was conducted on a commercial farm with reasonably effective animal management, so baseline welfare was likely satisfactory.

The athlete gut microbiota: state of the art and practical guidance.

The gut microbiota has been proposed to grant the athlete a metabolic advantage that might be key when optimising performance. While a taxonomic core set of microorganisms characterising the athlete's gut microbiota has not been delineated, some compositional features might be associated with improved metabolic efficiency, which appears to be driven by the production of bacterial metabolites, such as short-chain fatty acids. Not only long-term exercise but also dietary patterns associated with high-level sports practice contribute to this microbial environment, yet isolating the impact of individual dietary components is challenging. The present review synthetises the available evidence on the compositional aspects of the athlete's gut microbiota, discusses mechanisms involved in the bidirectional association between exercise and the gut environment, and evaluates the role of athletes' diet in this interplay. Additionally, a practical approach to indicators commonly reported in metagenomic and metabolomic analyses is provided to explore how these insights can translate to support dietary protocols.

Comprehensive characterisation and cryopreservation optimisation of buffalo (Bubalus bubalis) adipose tissue-derived mesenchymal stem cells

Over half of the world's buffalo (Bubalus bubalis) inhabit India, and buffaloes frequently encounter health challenges that resist conventional treatments, prompting the exploration of alternative therapeutic strategies. One promising approach is stem cell therapy, particularly multipotent mesenchymal/stromal stem cells (MSCs). These cells have shown significant efficacy in addressing various diseases in livestock that exhibit resistance to conventional therapies. Adipose tissue-derived MSCs (ADSCs) have garnered attention due to their accessibility and robust expansion potential. The current study comprehensively characterises buffalo ADSCs (bADSCs), confirming their identity as MSCs capable of differentiating into diverse cell lineages—the identified characteristics position bADSCs as promising candidates for applications in regenerative medicine, applicable in veterinary contexts. Notably, the study established that a cryoprotective solution comprising 10 % dimethyl sulfoxide and 90 % fetal bovine serum is optimal for preserving bADSCs. This cryoprotective solution maintains vital parameters, including viability, apoptosis, senescence, cell adherence, adherent cell viability, metabolic and clonogenic efficiency, and the activity of reactive oxygen species and trilineage differentiation potential following thawing. These findings lay the foundation for developing a cryo-banking system for bADSCs. Subsequent research efforts are focused on exploring the therapeutic potential of bADSCs in specific disease models and clinical settings. The outcomes of such investigations may pave the way for innovative and effective treatments, further enhancing our understanding of the regenerative capabilities of bADSCs.

Serial adaptive laboratory evolution enhances mixed carbon metabolic capacity of Escherichia coli

Microbes have inherent capacities for utilizing various carbon sources, however they often exhibit sub-par fitness due to low metabolic efficiency. To test whether a bacterial strain can optimally utilize multiple carbon sources, Escherichia coli was serially evolved in L-lactate and glycerol. This yielded two end-point strains that evolved first in L-lactate then in glycerol, and vice versa. The end-point strains displayed a universal growth advantage on single and a mixture of adaptive carbon sources, enabled by a concerted action of carbon source-specialists and generalist mutants. The combination of just four variants of glpK, ppsA, ydcI, and rph-pyrE, accounted for more than 80% of end-point strain fitness. In addition, machine learning analysis revealed a coordinated activity of transcriptional regulators imparting condition-specific regulation of gene expression. The effectiveness of the serial adaptive laboratory evolution (ALE) scheme in bioproduction applications was assessed under single and mixed-carbon culture conditions, in which serial ALE strain exhibited superior productivity of acetoin compared to ancestral strains. Together, systems-level analysis elucidated the molecular basis of serial evolution, which hold potential utility in bioproduction applications.

Center of mass position does not drive energetic costs during climbing.

Climbing animals theoretically should optimize the energetic costs of vertical climbing while also maintaining stability. Many modifications to climbing behaviors have been proposed as methods of satisfying these criteria, focusing on controlling the center of mass (COM) during ascent. However, the link between COM movements and metabolic energy costs has yet to be evaluated empirically. In this study, we manipulated climbing conditions across three experimental setups to elicit changes in COM position, and measured the impact of these changes upon metabolic costs across a sample of 14 humans. Metabolic energy was assessed via open flow respirometry, while COM movements were tracked both automatically and manually. Our findings demonstrate that, despite inducing variation in COM position, the energetic costs of climbing remained consistent across all three setups. Differences in energetic costs were similarly not affected by body mass; however, velocity had a significant impact upon both cost of transport and cost of locomotion, but such a relationship disappeared when accounting for metabolic costs per stride. These findings suggest that climbing has inescapable metabolic demands driven by gaining height, and that attempts to mitigate such a cost, with perhaps the exception of increasing speed, have only minimal impacts. We also demonstrate that metabolic and mechanical energy costs are largely uncorrelated. Collectively, we argue that these data refute the idea that efficient locomotion is the primary aim during climbing. Instead, adaptations towards effective climbing should focus on stability and reducing the risk of falling, as opposed to enhancing the metabolic efficiency of locomotion.

Some plasma biomarkers of residual feed intake in beef cattle remain consistent regardless of intake level

This study investigated whether plasma biomarkers of residual feed intake (RFI), identified under ad libitum feeding conditions in beef cattle, remained consistent during feed restriction. Sixty Charolais crossbred young bulls were divided into two groups for a crossover study. Group A was initially fed ad libitum (first test) and then restricted (second test) on the same diet, while Group B experienced the opposite sequence. Blood samples were collected from the 12 most divergent RFI animals in each group at the end of the first test and again after the second test. 12 plasma variables consistently increased, while three consistently decreased during feed restriction (FDR < 0.05). Only two metabolites, α-aminoadipic acid for Group A and 5-aminovaleric acid for Group B, were associated with RFI independent of feed intake level (FDR < 0.05), demonstrating moderate-to-high repeatability across feeding levels (intraclass correlation coefficient ≥ 0.59). Notably, both metabolites belong to the same metabolic pathway: lysine degradation. These metabolites consistently correlated with RFI, irrespective of fluctuations in feed intake, indicating a connection to individual metabolic processes influencing feed efficiency. These findings suggest that a portion of RFI phenotypic variance is inherent to an individual’s metabolic efficiency beyond variations in feed intake.

Energy requirement for primiparous Holstein × Gyr crossbred dairy cows

Our objective was to estimate the requirements of metabolizable energy (ME) and NEM of lactating and dry cows, the efficiency of ME utilization for milk production (kl) and tissue gain (kg), and the use of body energy mobilization for milk production (kt) throughout the lactation of primiparous crossbred Holstein × Gyr cows, using open-circuit respiration chambers. Twenty-nine primiparous Holstein × Gyr crossbred cows with an initial BW averaging 563 ± 40.1 kg and 2.5 ± 0.09 yr old were used throughout lactation and dry periods. The cows were kept nonpregnant throughout the study to eliminate possible confounding factors. Apparent digestibility assays, followed by calorimeter measurements, were performed 6 times throughout the lactation period. In the dry-off period, the cows were also evaluated but fed with restricted intake (DMI = 1.1% BW/d) to achieve heat production close to maintenance. After 21 d of diet adaptation, an apparent digestibility assay followed by calorimeter measurements was performed. Parameter estimates for lactation period were obtained by mixed models including lactation stage as repeated measures. For restricted feeding at dry-off and fasting period assays, the requirements were estimated by exponential regression. For whole lactation, the values of the ME requirement for maintenance (MEM) and NEM were 0.588 and 0.395 MJ/BW0.75, respectively. The efficiencies of kl, kg, and kt were 0.672, 0.771, and 0.814, respectively. However, MEM and NEM were higher in early and mid lactation than late, whereas kl was higher in early than other lactation stages. Dry and nonpregnant cows had MEM of 0.434 MJ/BW0.75 and NEM of 0.351 MJ/BW0.75 for maintenance level, and MEM of 0.396 MJ/BW0.75 and NEM of 0.345 MJ/BW0.75 for fasting metabolism level, and efficiency of ME utilization for maintenance was 0.80. Our findings confirmed that F1 crossbred Holstein × Gyr dairy cows have differences in energy requirement and efficiency throughout the lactation stages, suggesting the use of different values in each stage. The estimated values of energy requirement for maintenance and efficiencies for primiparous lactating crossbred Holstein × Gyr were similar to those reported in the literature in specific studies and requirements systems.

Interleukin-4 inhibits the hypothalamic appetite control by modulating the insulin-AKT and JAK-STAT signaling in leptin mutant mice.

Our previous research identified interleukin-4 (IL-4) as a key regulator of glucose/lipid metabolism, circulatory leptin levels, and insulin action, suggesting its potential as a therapeutic target for obesity and related complications. This study aimed to further elucidate the role of IL-4 in regulating hypothalamic appetite-controlling neuropeptides using leptin dysfunctional Leptin145E/145E mice as the experimental model. IL-4 significantly reduces body weight, food intake, and serum glucose levels. Our data demonstrated that IL-4 exhibits multiple functions in regulating hypothalamic appetite control, including downregulating orexigenic agouti-related peptide and neuropeptide Y levels, promoting expression of anorexigenic proopiomelanocortin, alleviating microenvironmental hypothalamic inflammation, enhancing leptin and insulin pathway, and attenuating insulin resistance. Furthermore, IL-4 promotes uncoupling protein 1 expression of white adipose tissue (WAT), suggesting its role in triggering WAT-beige switch. In summary, this study uncovers novel function of IL-4 in mediating food-intake behaviors and metabolic efficiency by regulating hypothalamic appetite-control and WAT browning activities. These findings support the therapeutic potential of targeting hypothalamic inflammation and reducing adiposity through IL-4 intervention for tackling the pandemic increasing prevalence of obesity and associated metabolic disorders.

Feedback regulation between AMPK and HIF-1α contributes to color stability via energy metabolism and mitochondrial efficiency regulation of yak meat

Despite the well-established individual roles of AMP-activated protein kinase (AMPK) and hypoxia-inducible factor-1α (HIF-1α) in sensing energy stress and/or hypoxia in postmortem muscle, a knowledge gap persists regarding their interplay and the consequent impact on the yak meat color stability. This study aimed to elucidate the AMPK–HIF–1α interaction and its consequential impact on mitochondrial functionality, energy metabolism, and ultimately, color attributes. Postmortem yak longissimus thoracis et lumborum (LTL) muscles were incubated with saline, AMPK inhibitor (Compound C), Compound C plus HIF-1α activator (DMOG), and Compound C plus HIF-1α inhibitor (YC-1) for 0, 6, 12, 24, 72, and 120 h, respectively. Results indicate that Compound C hindered the nuclear translocation of HIF-1α (P < 0.001), in turn, DMOG upregulated AMPK protein levels (P < 0.05) by a yet unknown mechanism. Mass spectrometry analysis identified seven AMPK-induced phosphorylation sites (Ser58, Thr63, Ser65, Tyr66, Thr677, Ser14, and Ser15) mapped onto three phosphopeptides on HIF-1α. Moreover, Compound C induced a significant reduction in energy metabolism levels, evidenced by decreased glycogen degradation, lactate accumulation, and pH decline (P < 0.05). Besides, Compound C promoted a consistently decreased mitochondrial protein yield, reduced NADH content, and OCR (P < 0.05). However, DMOG attenuated the effects of Compound C on mitochondrial efficiency, and interconversion of oxy-to deoxymyoglobin. Collectively, these findings establish the collaborative influence of AMPK and HIF-1α on postmortem energy metabolism, concurrently emphasizing their antagonistic effects on mitochondrial function.

Molecular mechanisms for selective action of afidopyropen to Myzus persicae and Coccinella septempunctata.

Afidopyropen is a novel insecticide with high selectivity between sucking insects such as the peach aphids Myzus persicae and natural enemies like the seven-spotted lady beetle Coccinella septempunctata. However, the mechanisms of selective action for afidopyropen remain unknown. The LC50 values of afidopyropen to the 1st-4th instar larvae and adult C. septempunctata were 372- to more than 7267-fold higher than that to adult M. persicae. Though the activity of cytochrome P450s in M. persicae was 6.1- to 7.5-fold higher than that in C. septempunctata, the latter has much higher activities of carboxylesterase (CarEs) and glutathione S-transferases (GSTs), and the crude enzyme of C. septempunctata and M. persicae showed similar metabolism efficiency to afidopyropen. Molecular docking results demonstrated that afdopyropen showed higher binding affinity to the vanilloid-type transient receptor potential (TRPV) channel of M. persicae (-9.1 kcal/mol) than to that of C. septempunctata (-8.2 kcal/mol). And the EC50 value of afdopyropen to the TRPV channel of C. septempunctata (41 360 nM) was 19 885-fold higher than that in M. persicae (2.08 nM). Our results demonstrated that the significantly different sensitivity of M. persicae and C. septempunctata TRPV channel to afidopyropen play a key role in the high selectivity of afidopyropen. These findings provide new insights into the selective mechanisms of afidopyropen against insect pests and natural enemies as well as the theory support for coordinated application of chemical control and biological control. © 2024 Society of Chemical Industry.

Restructuring of soil food webs reduces carbon storage potential in boreal peatlands

Microbial and faunal decomposers regulate the flux of carbon and nitrogen belowground, thus controlling the storage/release of carbon and nitrogen in soil systems. Warming is anticipated to alter decomposer biomass, and accelerate organismal metabolism and soil carbon release. We parameterized six soil food webs using empirical data for 18 trophic nodes at two boreal peatland sites under three climate scenarios (control, +2 °C, +4 °C), and model carbon and nitrogen flux, loss and retention using an energetic ecostoichiometric food web model. Differences in microbial biomass between sites dictated flux under warming. The community biomass of the fungal-dominated site was more impacted by warming, but fluxes were more responsive to warming at the bacterial-dominated site. Decreased metabolic efficiency of the soil food web at both sites in response to warming led to greater per capita carbon losses, indicating the long-term carbon storage potential of both systems is diminished.

Progress of Crude Oil Gasification Technology Assisted by Microorganisms in Reservoirs.

Crude oil gasification bacteria, including fermenting bacteria, hydrocarbon-oxidizing bacteria, reducing bacteria, and methanogenic bacteria, participate in multi-step reactions involving initial activation, intermediate metabolism, and the methanogenesis of crude oil hydrocarbons. These bacteria degrade crude oil into smaller molecules such as hydrogen, carbon dioxide, acetic acid, and formic acid. Ultimately, they convert it into methane, which can be utilized or stored as a strategic resource. However, the current challenges in crude oil gasification include long production cycles and low efficiency. This paper provides a summary of the microbial flora involved in crude oil gasification, the gasification metabolism pathways within reservoirs, and other relevant information. It specifically focuses on analyzing the factors that affect the efficiency of crude oil gasification metabolism and proposes suggestions for improving this efficiency. These studies deepen our understanding of the potential of reservoir ecosystems and provide valuable insights for future reservoir development and management.

Abstract 45: Driving AMPK signaling in CD4+ CART cells enhances metabolic capacity, memory formation, and anti-leukemia activity

Abstract Background: While Chimeric Antigen Receptor (CAR)T cell therapy has seen great success in pediatric and young adult acute lymphoblastic leukemia, up to 50% of patients will relapse following treatment. Increased memory formation and mitochondrial capacity, particularly in the CD4+ subset, have been linked to improved CART cell function and enhanced in vivo persistence, leading to long-term relapse-free survival. AMP-activated protein kinase (AMPK) is a cellular energy sensor responsible for promoting metabolic efficiency and T cell memory formation. We have previously demonstrated AMPK activity can be increased in human T cells via overexpression of the AMPKγ2 domain. We hypothesized that overexpression of AMPKγ2 in CART cells would enhance their metabolic capacity and improve their anti-leukemia function. Methods: Human CART cells bearing a CD19-CAR utilizing a 41BB costimulatory domain were generated from healthy human donors via lentiviral transduction and co-transduced with AMPKγ2 (AMPK) or an empty vector (EV) control. Flow sorting for the co-transduced populations yielded &amp;gt;95% CD4+ CART cells. CARTs were expanded in IL-2 for approximately 2 weeks, followed by overnight stimulation and subsequent metabolic analysis using the Seahorse Metabolic Analyzer. Memory status was assessed by CD62L and CCR7 co-expression. In vitro CART function was assessed using Zs-green+ NALM6 targets, with loss of green fluorescence over time measured on the Incucyte analyzer. Where indicated, tumor conditioned media was harvested from 72-hour NALM6 cultures. For in vivo experiments, immunodeficient NOD-scid IL2Rγnull (NSG) mice were injected with luciferase+ NALM6 targets, followed one week later by AMPK- or EV-CARTs. Leukemia burden, via IVIS imaging, and survival were followed over time. Results: CD4+ CARTs co-transduced with AMPKγ2 (AMPK-CARTs) increased oxygen consumption, maximal respiration, and spare respiratory capacity following overnight stimulation by ~20% compared to CARTs co-transduced with the EV (EV-CARTs) (p&amp;lt;0.05). Following expansion, CD62L+CCR7+ central memory cells were 4.5-fold more abundant in the AMPK-CART group (2.4-6.2-fold, p&amp;lt;0.01). In vitro, while AMPK-CARTs demonstrated similar cytotoxicity against NALM6 targets as EV-CARTs in standard media, they mediated faster killing of NALM6 targets when challenged in tumor conditioned media (p&amp;lt;0.001). In vivo, recipients of AMPK-CARTs showed a consistent decrease in tumor burden as measured by median radiance values, translating to a significant survival advantage (p&amp;lt;0.05). Conclusions: Increasing AMPK signaling in CD4+ CARTs via overexpression of AMPKγ2 improved metabolic profile, increased memory generation, and enhanced toxicity against leukemia targets both in vitro and in vivo. Together, these features make elevating AMPK signaling an attractive method to increase the efficacy of CART therapy. Citation Format: Erica Braverman, Herbert Schuler, Mengtao Qin, Craig Byersdorfer. Driving AMPK signaling in CD4+ CART cells enhances metabolic capacity, memory formation, and anti-leukemia activity [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 45.

Divergent responses in microbial metabolic limitations and carbon use efficiency to variably sized polystyrene microplastics in soil

AbstractMicroplastics, considered emerging contaminants, have been accumulating excessively within soil ecosystems, conferring potentially detrimental effects with respect to soil carbon turnover and pools. As a major participant in soil carbon processes, microplastics affecting microorganisms may be one of the main agents affecting soil carbon dynamics. However, the microbial metabolism processes through which microplastics affect soil carbon dynamics remain unclear. Therefore, this study aimed to assess the impact of variously sized (1300, 800, 100, and 0.1 μm) polystyrene microplastics on soil microbial metabolism. Soil microplastics of all sizes invariably and consistently affected microbial metabolism, though nanomicroplastics (0.1 μm) stressed soil microorganisms more than micron‐microplastics. Furthermore, microplastics inhibited both microbial carbon use efficiency (CUE) and respiration, the exception being the CUE in the 1300 μm microplastics treatment. As microplastic particle size decreased, the suppressive influence of microplastics on microbial respiration was gradually lost, the inhibitory effect on microbial CUE increased steadily, and the impact on microorganisms shifted from extracellular to intracellular, with intracellular microplastics exhibiting higher toxicity than extracellular microplastics. We used stoichiometric models to provide precise projections of microbial metabolism features associated with microplastic contamination, thereby enhancing the understanding of the effects of microplastic contamination on the carbon cycle and soil ecosystem.

Functional insight into multi-omics-based interventions for climatic resilience in sorghum (Sorghum bicolor): a nutritionally rich cereal crop.

Thearticle highlights omics-based interventions in sorghum to combat food and nutritional scarcity in the future. Sorghum with its unique ability to thrive in adverse conditions, has become a tremendous highly nutritive, and multipurpose cereal crop. It is resistant to various types of climatic stressors which will pave its way to a future food crop. Multi-omics refers to the comprehensive study of an organism at multiple molecular levels, including genomics, transcriptomics, proteomics, and metabolomics. Genomic studies have provided insights into the genetic diversity of sorghum and led to the development of genetically improved sorghum. Transcriptomics involves analysing the gene expression patterns in sorghum under various conditions. This knowledge is vital for developing crop varieties with enhanced stress tolerance. Proteomics enables the identification and quantification of the proteins present in sorghum. This approach helps in understanding the functional roles of specific proteins in response to stress and provides insights into metabolic pathways that contribute to resilience and grain production. Metabolomics studies the small molecules, or metabolites, produced by sorghum, provides information about the metabolic pathways that are activated or modified in response to environmental stress. This knowledge can be used to engineer sorghum varieties with improved metabolic efficiency, ultimately leading to better crop yields. In this review, we have focused on various multi-omics approaches, gene expression analysis, and different pathways for the improvement of Sorghum. Applying omics approaches to sorghum research allows for a holistic understanding of its genome function. This knowledge is invaluable for addressing challenges such as climate change, resource limitations, and the need for sustainable agriculture.

Interplay between developmental cues and rhizosphere signals from mycorrhizal fungi shape root anatomy, impacting crop productivity

Abstract Background The rhizosphere is the interface between roots and the soil and the site of nutrient and water uptake for plant growth. Root anatomy and the physical, chemical, and biological components of the rhizosphere interact to influence plant growth. Several root developmental and rhizosphere signals combine in the patterning of root cortical anatomy and have implications for the plant’s hydro-mineral nutrition and carbon partitioning and therefore crop productivity, especially in edaphic stress. Scope Here, we highlight how mutualistic mycorrhizal fungi from the rhizosphere mobilize plant molecular actors controlling root anatomical traits, including cortical cell size, to facilitate their establishment and accommodation within the cortex. We explore the effects on plant growth and stress tolerance that may result from the changes in root anatomy driven by interactions with arbuscular mycorrhizal fungi, including altering the metabolic efficiency required for nutrient exploitation. We also discuss opportunities for understanding the genetic control of root anatomy and rhizosphere interactions to enable a comprehensive understanding of the benefits and trade-offs of root-rhizosphere interactions for more productive crops.

Efficiency Characteristics and Evolution Patterns of Urban Carbon Metabolism of Production-Living-Ecological Space in Beijing-Tianjin-Hebei Region

This study explored the carbon metabolism efficiency of a production-living-ecological space system, which is of great significance for regional factor integration and spatial optimization. In this study, the material flow analysis method was introduced to establish a framework for evaluating the carbon metabolism efficiency of the production-living-ecological space system, and the super-efficiency DEA model and Malmquist index were used to empirically analyze the spatio-temporal distribution, dynamic change, and evolution patterns of the carbon metabolism efficiency of production-living-ecological space in the Beijing-Tianjin-Hebei Region, China, from 2000 to 2020 on the basis of the urban metabolic perspective. The results showed that:① the carbon metabolism efficiency of the production-living-ecological space showed a fluctuating growth trend, indicating the significant spatial differentiation of carbon metabolism efficiency in each city. There was a low overall carbon metabolism efficiency level, with a distribution pattern of being high in the middle and low in the north and south. ② The Malmquist index showed that the Total Factor Productivity (TFP) of carbon metabolism efficiency was greater than 1, and both the Technical Change (TC) and Pure Efficiency Change (PEC) were less than 1, in which the TFP showed an increasing trend, whereas there was no significant contribution of technological progress or pure technical efficiency to carbon metabolism efficiency. The total factor productivity of more than 50% of the cities showed an improving trend, only 38.46% of which made technological progress in improving carbon metabolism efficiency, and more than half of the urban pure technical efficiency showed a decreasing trend, in which the technical efficiency change and scale efficiency change were greater than 1 in most cities. ③ There were different types of carbon efficiency characteristics in each city, and according to the movement rules of the corresponding points in the quartile map, the evolution patterns of tourism industry efficiency were classified into stable, reciprocating, progressive, and abrupt. Therefore, local governments should adopt differentiated strategies to reasonably allocate spatial resources of production-living-ecological space and improve the technical level and scale efficiency, so as to improve the efficiency of urban carbon metabolism.