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Cell Jun 2024Microbial hydrogen (H) cycling underpins the diversity and functionality of diverse anoxic ecosystems. Among the three evolutionarily distinct hydrogenase superfamilies...
Microbial hydrogen (H) cycling underpins the diversity and functionality of diverse anoxic ecosystems. Among the three evolutionarily distinct hydrogenase superfamilies responsible, [FeFe] hydrogenases were thought to be restricted to bacteria and eukaryotes. Here, we show that anaerobic archaea encode diverse, active, and ancient lineages of [FeFe] hydrogenases through combining analysis of existing and new genomes with extensive biochemical experiments. [FeFe] hydrogenases are encoded by genomes of nine archaeal phyla and expressed by H-producing Asgard archaeon cultures. We report an ultraminimal hydrogenase in DPANN archaea that binds the catalytic H-cluster and produces H. Moreover, we identify and characterize remarkable hybrid complexes formed through the fusion of [FeFe] and [NiFe] hydrogenases in ten other archaeal orders. Phylogenetic analysis and structural modeling suggest a deep evolutionary history of hybrid hydrogenases. These findings reveal new metabolic adaptations of archaea, streamlined H catalysts for biotechnological development, and a surprisingly intertwined evolutionary history between the two major H-metabolizing enzymes.
Topics: Archaea; Archaeal Proteins; Genome, Archaeal; Hydrogen; Hydrogenase; Iron-Sulfur Proteins; Models, Molecular; Phylogeny; Protein Structure, Tertiary
PubMed: 38866018
DOI: 10.1016/j.cell.2024.05.032 -
Redox Biology Aug 2024Hydrogen sulfide (HS) has recently been recognized as an important gaseous transmitter with multiple physiological effects in various species. Previous studies have...
Hydrogen sulfide (HS) has recently been recognized as an important gaseous transmitter with multiple physiological effects in various species. Previous studies have shown that HS alleviated heat-induced ganoderic acids (GAs) biosynthesis, an important quality index of Ganoderma lucidum. However, a comprehensive understanding of the physiological effects and molecular mechanisms of HS in G. lucidum remains unexplored. In this study, we found that heat treatment reduced the mitochondrial membrane potential (MMP) and mitochondrial DNA copy number (mtDNAcn) in G. lucidum. Increasing the intracellular HS concentration through pharmacological and genetic means increased the MMP level, mtDNAcn, oxygen consumption rate level and ATP content under heat treatment, suggesting a role for HS in mitigating heat-caused mitochondrial damage in G. lucidum. Further results indicated that HS activates sulfide-quinone oxidoreductase (SQR) and complex III (Com III), thereby maintaining mitochondrial homeostasis under heat stress in G. lucidum. Moreover, SQR also mediated the negative regulation of HS to GAs biosynthesis under heat stress. Furthermore, SQR might be persulfidated under heat stress in G. lucidum. Thus, our study reveals a novel physiological function and molecular mechanism of HS signalling under heat stress in G. lucidum with broad implications for research on the environmental response of microorganisms.
Topics: Hydrogen Sulfide; Reishi; Triterpenes; Mitochondria; Homeostasis; Heat-Shock Response; Membrane Potential, Mitochondrial; Quinone Reductases; DNA, Mitochondrial; Electron Transport Complex III
PubMed: 38865903
DOI: 10.1016/j.redox.2024.103227 -
Journal of Agricultural and Food... Jun 2024In this work, lactoferrin (LF)-chitosan (CS) composite hydrogels with good loading capacity of thermosensitive bioactive substances were successfully obtained by...
In this work, lactoferrin (LF)-chitosan (CS) composite hydrogels with good loading capacity of thermosensitive bioactive substances were successfully obtained by microbial transglutaminase (MTG)-induced cross-linking. We evaluated the rheological, textural, and microstructural characteristics of the composite hydrogels under different conditions. The results demonstrated that the concentrations of LF and CS as well as the amount of MTG could regulate the textural properties, rheological properties, and water holding capability. The results of FTIR and fluorescence spectroscopy indicated that the main interactions within the composite gel were hydrogen and isopeptide bonds. Additionally, in vitro digestion simulation results verified that riboflavin kept stable in stomach due to the protection of LF-CS composite hydrogels and was released in small intestine. These results suggested that thermosensitive bioactive substance could be encapsulated and delivered by the LF-CS composite hydrogel, which could be applied in lots of potential applications in functional food as a new material.
Topics: Transglutaminases; Hydrogels; Chitosan; Lactoferrin; Rheology; Bacterial Proteins; Drug Delivery Systems; Drug Carriers; Digestion
PubMed: 38865607
DOI: 10.1021/acs.jafc.4c01551 -
Science Advances Jun 2024Nitrogenase plays a key role in the global nitrogen cycle; yet, the evolutionary history of nitrogenase and, particularly, the sequence of appearance between the...
Nitrogenase plays a key role in the global nitrogen cycle; yet, the evolutionary history of nitrogenase and, particularly, the sequence of appearance between the homologous, yet distinct NifDK (the catalytic component) and NifEN (the cofactor maturase) of the extant molybdenum nitrogenase, remains elusive. Here, we report the ability of NifEN to reduce N at its surface-exposed L-cluster ([FeSC]), a structural/functional homolog of the M-cluster (or cofactor; [(-homocitrate)MoFeSC]) of NifDK. Furthermore, we demonstrate the ability of the L-cluster-bound NifDK to mimic its NifEN counterpart and enable N reduction. These observations, coupled with phylogenetic, ecological, and mechanistic considerations, lead to the proposal of a NifEN-like, L-cluster-carrying protein as an ancient nitrogenase, the exploration of which could shed crucial light on the evolutionary origin of nitrogenase and related enzymes.
Topics: Nitrogenase; Phylogeny; Nitrogen; Molybdoferredoxin; Models, Molecular; Bacterial Proteins; Nitrogen Fixation
PubMed: 38865457
DOI: 10.1126/sciadv.ado6169 -
Nan Fang Yi Ke Da Xue Xue Bao = Journal... May 2024To investigate the mechanisms that mediate the neuroprotective effect of the intestinal microbial metabolite sodium butyrate (NaB) in a mouse model of Parkinson's...
OBJECTIVE
To investigate the mechanisms that mediate the neuroprotective effect of the intestinal microbial metabolite sodium butyrate (NaB) in a mouse model of Parkinson's disease (PD) the gut-brain axis.
METHODS
Thirty-nine 7-week-old male C57BL/6J mice were randomized equally into control group, PD model group, and NaB treatment group. In the latter two groups, PD models were established by intraperitoneal injection of 30 mg/kg 1-methyl-4-phenyl-1, 2, 3, 6-tetrahydropyridine (MPTP) once daily for 5 consecutive days, and normal saline was injected in the control group. After modeling, the mice received daily gavage of NaB (300 mg/kg) or an equal volume of saline for 14 days. Behavioral tests were carried out to assess the changes in motor function of the mice, and Western blotting was performed to detect the expressions of tyrosine hydroxylase (TH) and -synuclein (-syn) in the striatum and nuclear factor-κB (NF-κB), tumor necrosis factor (TNF-), interleukin 6 (IL-6), and the tight junction proteins ZO-1, Occludin, and Claudinin the colon. HE staining was used to observe inflammatory cell infiltration in the colon of the mice. RNA sequencing analysis was performed to identify the differentially expressed genes in mouse colon tissues, and their expressions were verified using qRT-PCR and Western blotting.
RESULTS
The mouse models of PD with NaB treatment showed significantly increased movement speed and pulling strength of the limbs with obviously upregulated expressions of TH, Occludin, and Claudin and downregulated expressions of -syn, NF-κB, TNF-, and IL-6 (all < 0.05). HE staining showed that NaB treatment significantly ameliorated inflammatory cell infiltration in the colon of the PD mice. RNA sequencing suggested that Bmal1 gene probably mediated the neuroprotective effect of NaB in PD mice ( < 0.05).
CONCLUSION
NaB can improve motor dysfunction, reduce dopaminergic neuron loss in the striatum, and ameliorate colonic inflammation in PD mice possibly through a mechanism involving Bmal1.
Topics: Animals; Mice; Butyric Acid; Male; Mice, Inbred C57BL; Neuroprotective Agents; Disease Models, Animal; Parkinson Disease; alpha-Synuclein; Tumor Necrosis Factor-alpha; NF-kappa B; Interleukin-6; Tyrosine 3-Monooxygenase; 1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine; Corpus Striatum; Occludin; Brain-Gut Axis
PubMed: 38862445
DOI: 10.12122/j.issn.1673-4254.2024.05.09 -
BMJ Open Jun 2024This systematic review and meta-analysis aimed to comprehensively assess the impact of weekly iron-folic acid supplementation (WIFAS) on the nutrition, health and... (Meta-Analysis)
Meta-Analysis
Weekly iron-folic acid supplementation and its impact on children and adolescents iron status, mental health and school performance: a systematic review and meta-analysis in sub-Saharan Africa.
OBJECTIVE
This systematic review and meta-analysis aimed to comprehensively assess the impact of weekly iron-folic acid supplementation (WIFAS) on the nutrition, health and educational outcomes of children and adolescents in sub-Saharan Africa.
DESIGN
A systematic review and meta-analysis was used.
DATA SOURCES
Five databases, namely, MEDLINE, Scopus, Web of Science, Cochrane Library and Google Scholar, were systematically searched for relevant articles up to 23 August 2023.
ELIGIBILITY CRITERIA
It was focused on randomised controlled trials involving children and adolescents in sub-Saharan Africa, exploring the effects of iron supplementation on various outcomes, such as serum ferritin and haemoglobin levels, anaemia, mental health and school performance.
DATA EXTRACTION AND SYNTHESIS
The Joanna Briggs Institute Critical Appraisal tools were used for quality assessment, with two independent reviewers thoroughly evaluating each paper. Using the Cochrane risk of bias tool, we evaluated the certainty of evidence such as the risk of bias, inconsistency, indirectness, imprecision and publication bias.
RESULTS
A systematic review of 10 articles revealed that WIFAS significantly increased serum ferritin levels in adolescent girls (Hedge's g=0.53, 95% CI 0.28 to 0.78; heterogeneity I=41.21%, p<0.001) and haemoglobin levels in school-aged children (Hedge's g=0.37, 95% CI 0.01 to 0.73; heterogeneity I=91.62%, p<0.001). The analysis further demonstrated a substantial reduction in the risk of anaemia by 20% (risk ratio=0.8, 95% CI 0.69 to 0.93; heterogeneity I=28.12%, p<0.001).
CONCLUSION
WIFAS proved effective in enhancing serum ferritin and haemoglobin concentrations and lowering the risk of anaemia in school-aged children and adolescents compared with a placebo. Similarly, there are not enough studies to examine the effects of WIFAS on school performance. However, information regarding mental health problems, mortality and potential side effects remains insufficient.
PROSPERO REGISTRATION NUMBER
CRD42023397898.
Topics: Humans; Child; Adolescent; Dietary Supplements; Africa South of the Sahara; Mental Health; Iron; Folic Acid; Ferritins; Anemia, Iron-Deficiency; Hemoglobins; Randomized Controlled Trials as Topic; Female; Nutritional Status
PubMed: 38862227
DOI: 10.1136/bmjopen-2024-084033 -
Molecular Brain Jun 2024Chronic perturbations of neuronal activity can evoke homeostatic and new setpoints for neurotransmission. Using chemogenetics to probe the relationship between neuronal...
Chronic perturbations of neuronal activity can evoke homeostatic and new setpoints for neurotransmission. Using chemogenetics to probe the relationship between neuronal cell types and behavior, we recently found reversible decreases in dopamine (DA) transmission, basal behavior, and amphetamine (AMPH) response following repeated stimulation of DA neurons in adult mice. It is unclear, however, whether altering DA neuronal activity via chemogenetics early in development leads to behavioral phenotypes that are reversible, as alterations of neuronal activity during developmentally sensitive periods might be expected to induce persistent effects on behavior. To examine the impact of developmental perturbation of DA neuron activity on basal and AMPH behavior, we expressed excitatory hM3D(Gq) in postnatal DA neurons in TH-Cre and WT mice. Basal and CNO- or AMPH-induced locomotion and stereotypy was evaluated in a longitudinal design, with clozapine N-oxide (CNO, 1.0 mg/kg) administered across adolescence (postnatal days 15-47). Repeated CNO administration did not impact basal behavior and only minimally reduced AMPH-induced hyperlocomotor response in adolescent TH-Cre mice relative to WT littermate controls. Following repeated CNO administration, however, AMPH-induced stereotypic behavior robustly decreased in adolescent TH-Cre mice relative to controls. A two-month CNO washout period rescued the diminished AMPH-induced stereotypic behavior. Our findings indicate that the homeostatic compensations that take place in response to chronic hM3D(Gq) stimulation during adolescence are temporary and are dependent on ongoing chemogenetic stimulation.
Topics: Animals; Amphetamine; Dopaminergic Neurons; Stereotyped Behavior; Clozapine; Locomotion; Mice; Male; Motor Activity; Mice, Transgenic; Tyrosine 3-Monooxygenase; Behavior, Animal; Integrases
PubMed: 38858755
DOI: 10.1186/s13041-024-01110-9 -
Journal of Inorganic Biochemistry Sep 2024CH functionalization, a promising frontier in modern organic chemistry, facilitates the direct conversion of inert CH bonds into many valuable functional groups. Despite... (Review)
Review
CH functionalization, a promising frontier in modern organic chemistry, facilitates the direct conversion of inert CH bonds into many valuable functional groups. Despite its merits, traditional homogeneous catalysis, often faces challenges in efficiency, selectivity, and sustainability towards this transformation. In this context, artificial metalloenzymes (ArMs), resulting from the incorporation of a catalytically-competent metal cofactor within an evolvable protein scaffold, bridges the gap between the efficiency of enzymatic transformations and the versatility of transition metal catalysis. Accordingly, ArMs have emerged as attractive tools for various challenging catalytic transformations. Additionally, the coming of age of directed evolution has unlocked unprecedented avenues for optimizing enzymatic catalysis. Taking advantage of their genetically-encoded protein scaffold, ArMs have been evolved to catalyze various CH functionalization reactions. This review delves into the recent developments of ArM-catalyzed CH functionalization reactions, highlighting the benefits of engineering the second coordination sphere around a metal cofactor within a host protein.
Topics: Metalloproteins; Catalysis; Protein Engineering; Hydrogen
PubMed: 38852295
DOI: 10.1016/j.jinorgbio.2024.112621 -
ACS Nano Jun 2024Ferritin, a spherical protein shell assembled from 24 subunits, functions as an efficient iron storage and release system through its channels. Understanding how various...
Ferritin, a spherical protein shell assembled from 24 subunits, functions as an efficient iron storage and release system through its channels. Understanding how various chemicals affect the structural behavior of ferritin is crucial for unravelling the origins of iron-related diseases in living organisms including humans. In particular, the influence of chemicals on ferritin's dynamics and iron release is barely explored at the single-protein level. Here, by employing optical nanotweezers using double-nanohole (DNH) structures, we examined the effect of ascorbic acid (reducing reagent) and pH on individual ferritin's conformational dynamics. The dynamics of ferritin increased as the concentration of ascorbic acid approached saturation. At pH 2.0, ferritin exhibited significant structural fluctuations and eventually underwent a stepwise disassembly into fragments. This work demonstrated the disassembly pathway and kinetics of a single ferritin molecule in solution. We identified four critical fragments during its disassembly pathway, which are 22-mer, 12-mer, tetramer, and dimer subunits. Moreover, we present single-molecule evidence of the cooperative disassembly of ferritin. Interrogating ferritin's structural change in response to different chemicals holds importance for understanding their roles in iron metabolism, hence facilitating further development of medical treatments for its associated diseases.
Topics: Ferritins; Kinetics; Optical Tweezers; Ascorbic Acid; Hydrogen-Ion Concentration; Protein Conformation; Iron; Humans
PubMed: 38850556
DOI: 10.1021/acsnano.4c01221 -
Cancer Control : Journal of the Moffitt... 2024Our objective is to develop a predictive model utilizing the ferritin and transferrin ratio (FTR) and clinical factors to forecast overall survival (OS) in breast cancer...
BACKGROUND
Our objective is to develop a predictive model utilizing the ferritin and transferrin ratio (FTR) and clinical factors to forecast overall survival (OS) in breast cancer (BC) patients.
METHODS
We conducted a retrospective analysis of clinical data from 2858 BC patients diagnosed between 2013 and 2021. Subsequently, the cohort of 2858 BC patients underwent random assignment into distinct subsets: a training cohort comprising 2002 patients and a validation cohort comprising 856 patients, maintaining a proportional ratio of 7:3. Employing multivariable Cox regression analysis within the training cohort, we derived a prognostic nomogram. The predictive performance was assessed using calibration curves, C-index, and decision curve analysis.
RESULTS
The final prognostic model included the TNM stage, subtype, hemoglobin levels, and the ferritin-transferrin ratio. The nomogram achieved a C-index of .794 (95% CI: .777-.810). The nomogram demonstrated superior predictive accuracy for OS at 3, 5, and 7 years for BC, with area under the time-dependent curves of .812, .782, and .773, respectively. These values notably outperformed those of the conventional TNM stage. Decision curve analysis reaffirmed the greater net benefit of our nomogram compared to the TNM stage. These findings were subsequently validated in the independent validation cohort.
CONCLUSION
The FTR-based prognostic model may predict a patient's OS better than the TNM stage in a clinical setting. The nomogram can provide an early, affordable, and reliable tool for survival prediction, as well as aid clinicians in treatment option-making and prognosis evaluation. However, further multi-center prospective trials are required to confirm the reliability of the existing nomogram.
Topics: Humans; Nomograms; Breast Neoplasms; Female; Ferritins; Transferrin; Middle Aged; Retrospective Studies; Prognosis; Adult; Aged; Neoplasm Staging
PubMed: 38850515
DOI: 10.1177/10732748241261553