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1.
Proc Natl Acad Sci U S A ; 120(33): e2305704120, 2023 08 15.
Article in English | MEDLINE | ID: mdl-37549277

ABSTRACT

Biocompatible and morphable hydrogels capable of multimode reprogrammable, and adaptive shape changes are potentially useful for diverse biomedical applications. However, existing morphable systems often rely on complicated structural designs involving cumbersome and energy-intensive fabrication processes. Here, we report a simple electric-field-activated protein network migration strategy to reversibly program silk-protein hydrogels with controllable and reprogrammable complex shape transformations. The application of a low electric field enables the convergence of net negatively charged protein cross-linking networks toward the anode (isoelectric point plane) due to the pH gradient generated in the process, facilitating the formation of a gradient network structure and systems suitable for three-dimensional shape change. These tunable protein networks can be reprogrammed or permanently fixed by control of the polymorphic transitions. We show that these morphing hydrogels are capable of conformally interfacing with biological tissues by programming the shape changes and a bimorph structure consisting of aligned carbon nanotube multilayers and the silk hydrogels was assembled to illustrate utility as an implantable bioelectronic device for localized low-voltage electrical stimulation of the sciatic nerve in a rabbit.


Subject(s)
Hydrogels , Silk , Animals , Rabbits , Silk/chemistry , Hydrogels/chemistry , Isoelectric Point , Biocompatible Materials/chemistry
2.
Circulation ; 2024 Apr 01.
Article in English | MEDLINE | ID: mdl-38557054

ABSTRACT

BACKGROUND: An imbalance of antiproliferative BMP (bone morphogenetic protein) signaling and proliferative TGF-ß (transforming growth factor-ß) signaling is implicated in the development of pulmonary arterial hypertension (PAH). The posttranslational modification (eg, phosphorylation and ubiquitination) of TGF-ß family receptors, including BMPR2 (bone morphogenetic protein type 2 receptor)/ALK2 (activin receptor-like kinase-2) and TGF-ßR2/R1, and receptor-regulated (R) Smads significantly affects their activity and thus regulates the target cell fate. BRCC3 modifies the activity and stability of its substrate proteins through K63-dependent deubiquitination. By modulating the posttranslational modifications of the BMP/TGF-ß-PPARγ pathway, BRCC3 may play a role in pulmonary vascular remodeling, hence the pathogenesis of PAH. METHODS: Bioinformatic analyses were used to explore the mechanism of BRCC3 deubiquitinates ALK2. Cultured pulmonary artery smooth muscle cells (PASMCs), mouse models, and specimens from patients with idiopathic PAH were used to investigate the rebalance between BMP and TGF-ß signaling in regulating ALK2 phosphorylation and ubiquitination in the context of pulmonary hypertension. RESULTS: BRCC3 was significantly downregulated in PASMCs from patients with PAH and animals with experimental pulmonary hypertension. BRCC3, by de-ubiquitinating ALK2 at Lys-472 and Lys-475, activated receptor-regulated Smad1/5/9 (Smad1/5/9), which resulted in transcriptional activation of BMP-regulated PPARγ, p53, and Id1. Overexpression of BRCC3 also attenuated TGF-ß signaling by downregulating TGF-ß expression and inhibiting phosphorylation of Smad3. Experiments in vitro indicated that overexpression of BRCC3 or the de-ubiquitin-mimetic ALK2-K472/475R attenuated PASMC proliferation and migration and enhanced PASMC apoptosis. In SM22α-BRCC3-Tg mice, pulmonary hypertension was ameliorated because of activation of the ALK2-Smad1/5-PPARγ axis in PASMCs. In contrast, Brcc3-/- mice showed increased susceptibility of experimental pulmonary hypertension because of inhibition of the ALK2-Smad1/5 signaling. CONCLUSIONS: These results suggest a pivotal role of BRCC3 in sustaining pulmonary vascular homeostasis by maintaining the integrity of the BMP signaling (ie, the ALK2-Smad1/5-PPARγ axis) while suppressing TGF-ß signaling in PASMCs. Such rebalance of BMP/TGF-ß pathways is translationally important for PAH alleviation.

3.
FASEB J ; 38(1): e23365, 2024 01.
Article in English | MEDLINE | ID: mdl-38069862

ABSTRACT

CD30 is a member of the tumor necrosis factor receptor (TNFR) superfamily and expressed in both normal and malignant lymphoid cells. However, the role of CD30 in lymphopoiesis is not known. In this study, we showed CD30 was expressed both in T and B cells, but its deficiency in mice had no effect on T- and B-cell development. In fact, CD30 deficiency attenuated B-cell response to T-cell-dependent antigens. The impaired B cell response in CD30-deficient mice is caused by the reduction of activation-induced cytidine deaminase (AID) expression. Moreover, CD30-deficient mice exhibited decreased TCR-mediated T cell proliferation and slightly impaired TCR signaling. High-throughput RNA sequencing analysis revealed that CD30 deficiency led to a decrease of FOXO-autophagy axis in T cells upon TCR stimulation. Thus, CD30 positively regulates T-cell-dependent immune response and T cell proliferation.


Subject(s)
Ki-1 Antigen , Lymphocyte Activation , T-Lymphocytes , Animals , Mice , Cell Proliferation , Ki-1 Antigen/genetics , Receptors, Antigen, T-Cell/genetics , T-Lymphocytes/immunology
4.
PLoS Biol ; 20(8): e3001739, 2022 08.
Article in English | MEDLINE | ID: mdl-35969610

ABSTRACT

Symbiotic nitrogen fixation (SNF) provides sufficient nitrogen (N) to meet most legume nutrition demands. In return, host plants feed symbionts carbohydrates produced in shoots. However, the molecular dialogue between shoots and symbionts remains largely mysterious. Here, we report the map-based cloning and characterization of a natural variation in GmNN1, the ortholog of Arabidopsis thaliana FLOWERING LOCUS T (FT2a) that simultaneously triggers nodulation in soybean and modulates leaf N nutrition. A 43-bp insertion in the promoter region of GmNN1/FT2a significantly decreased its transcription level and yielded N deficiency phenotypes. Manipulating GmNN1/GmFT2a significantly enhanced soybean nodulation, plant growth, and N nutrition. The near-isogenic lines (NILs) carrying low mRNA abundance alleles of GmNN1/FT2a, along with stable transgenic soybeans with CRISPR/Cas9 knockouts of GmNN1/FT2a, had yellower leaves, lower N concentrations, and fewer nodules than wild-type control plants. Grafting together with split-root experiments demonstrated that only shoot GmNN1/FT2a was responsible for regulating nodulation and thereby N nutrition through shoot-to-root translocation, and this process depends on rhizobial infection. After translocating into roots, shoot-derived GmNN1/FT2a was found to interact with GmNFYA-C (nuclear factor-Y subunit A-C) to activate symbiotic signaling through the previously reported GmNFYA-C-ENOD40 module. In short, the description of the critical soybean nodulation regulatory pathway outlined herein sheds novel insights into the shoot-to-root signaling required for communications between host plants and root nodulating symbionts.


Subject(s)
Arabidopsis , Glycine max , Arabidopsis/genetics , Arabidopsis/metabolism , Nitrogen/metabolism , Nitrogen Fixation , Plant Roots/genetics , Plant Roots/metabolism , Glycine max/genetics , Glycine max/metabolism , Symbiosis/genetics
5.
Proc Natl Acad Sci U S A ; 119(3)2022 01 18.
Article in English | MEDLINE | ID: mdl-35022232

ABSTRACT

Nitrogen fixation in soybean takes place in root nodules that arise from de novo cell divisions in the root cortex. Although several early nodulin genes have been identified, the mechanism behind the stimulation of cortical cell division during nodulation has not been fully resolved. Here we provide evidence that two paralogs of soybean SHORT-ROOT (GmSHR) play vital roles in soybean nodulation. Expression of GmSHR4 and GmSHR5 (GmSHR4/5) is induced in cortical cells at the beginning of nodulation, when the first cell divisions occur. The expression level of GmSHR4/5 is positively associated with cortical cell division and nodulation. Knockdown of GmSHR5 inhibits cell division in outer cortical layers during nodulation. Knockdown of both paralogs disrupts the cell division throughout the cortex, resulting in poorly organized nodule primordia with delayed vascular tissue formation. GmSHR4/5 function by enhancing cytokinin signaling and activating early nodulin genes. Interestingly, D-type cyclins act downstream of GmSHR4/5, and GmSHR4/5 form a feedforward loop regulating D-type cyclins. Overexpression of D-type cyclins in soybean roots also enhanced nodulation. Collectively, we conclude that the GmSHR4/5-mediated pathway represents a vital module that triggers cytokinin signaling and activates D-type cyclins during nodulation in soybean.


Subject(s)
Cyclins/metabolism , Glycine max/metabolism , Glycine max/physiology , Plant Proteins/chemistry , Plant Proteins/metabolism , Plant Root Nodulation/physiology , Root Nodules, Plant/physiology , Sequence Homology, Amino Acid , Cell Division , Cytokinins/metabolism , Gene Expression Regulation, Plant , Genes, Plant , Membrane Proteins/genetics , Membrane Proteins/metabolism , Plant Proteins/genetics , Signal Transduction
6.
BMC Biol ; 22(1): 4, 2024 01 02.
Article in English | MEDLINE | ID: mdl-38166816

ABSTRACT

BACKGROUND: The common carp (Cyprinus carpio) might best represent the domesticated allopolyploid animals. Although subgenome divergence which is well-known to be a key to allopolyploid domestication has been comprehensively characterized in common carps, the link between genetic architecture underlying agronomic traits and subgenome divergence is unknown in the selective breeding of common carps globally. RESULTS: We utilized a comprehensive SNP dataset in 13 representative common carp strains worldwide to detect genome-wide genetic variations associated with scale reduction, vibrant skin color, and high growth rate in common carp domestication. We identified numerous novel candidate genes underlie the three agronomically most desirable traits in domesticated common carps, providing potential molecular targets for future genetic improvement in the selective breeding of common carps. We found that independently selective breeding of the same agronomic trait (e.g., fast growing) in common carp domestication could result from completely different genetic variations, indicating the potential advantage of allopolyploid in domestication. We observed that candidate genes associated with scale reduction, vibrant skin color, and/or high growth rate are repeatedly enriched in the immune system, suggesting that domestication of common carps was often accompanied by the disease resistance improvement. CONCLUSIONS: In common carp domestication, asymmetric subgenome selection is prevalent, while parallel subgenome selection occurs in selective breeding of common carps. This observation is not due to asymmetric gene retention/loss between subgenomes but might be better explained by reduced pleiotropy through transposable element-mediated expression divergence between ohnologs. Our results demonstrate that domestication benefits from polyploidy not only in plants but also in animals.


Subject(s)
Carps , Domestication , Animals , Carps/genetics , Genome , Animals, Domestic/genetics , Phenotype
7.
Nano Lett ; 24(2): 667-671, 2024 Jan 17.
Article in English | MEDLINE | ID: mdl-38174941

ABSTRACT

We present a first-principles many-body perturbation theory study of nitrophenyl-doped (6,5) single-walled nanotubes (SWCNTs) to understand how sp3 doping impacts the excitonic properties. sp3-doped SWCNTs are promising as a class of optoelectronic materials with bright tunable photoluminescence, long spin coherence, and single-photon emission (SPE), motivating the study of spin excitations. We predict that the dopant results in a single unpaired spin localized around the defect site, which induces multiple low-energy excitonic peaks. By comparing optical absorption and photoluminescence from experiment and theory, we identify the transitions responsible for the red-shifted, defect-induced E11* peak, which has demonstrated SPE for some dopants; the presence of this state is due to both the symmetry-breaking associated with the defect and the presence of the defect-induced in-gap state. Furthermore, we find an asymmetry between the contribution of the two spin channels, suggesting that this system has potential for spin-selective optical transitions.

8.
Plant J ; 116(1): 234-250, 2023 10.
Article in English | MEDLINE | ID: mdl-37387536

ABSTRACT

Enhancers are critical cis-regulatory elements controlling gene expression during cell development and differentiation. However, genome-wide enhancer characterization has been challenging due to the lack of a well-defined relationship between enhancers and genes. Function-based methods are the gold standard for determining the biological function of cis-regulatory elements; however, these methods have not been widely applied to plants. Here, we applied a massively parallel reporter assay on Arabidopsis to measure enhancer activities across the genome. We identified 4327 enhancers with various combinations of epigenetic modifications distinctively different from animal enhancers. Furthermore, we showed that enhancers differ from promoters in their preference for transcription factors. Although some enhancers are not conserved and overlap with transposable elements forming clusters, enhancers are generally conserved across thousand Arabidopsis accessions, suggesting they are selected under evolution pressure and could play critical roles in the regulation of important genes. Moreover, comparison analysis reveals that enhancers identified by different strategies do not overlap, suggesting these methods are complementary in nature. In sum, we systematically investigated the features of enhancers identified by functional assay in A. thaliana, which lays the foundation for further investigation into enhancers' functional mechanisms in plants.


Subject(s)
Arabidopsis , Animals , Arabidopsis/genetics , Enhancer Elements, Genetic/genetics , Promoter Regions, Genetic/genetics , Transcription Factors/genetics , Epigenesis, Genetic
9.
BMC Genomics ; 25(1): 206, 2024 Feb 23.
Article in English | MEDLINE | ID: mdl-38395755

ABSTRACT

BACKGROUND: Pancreatic ductal adenocarcinoma (PDAC) is a lethal malignancy with a five-year survival rate of approximately 10%. Genetic mutations are pivotal drivers in PDAC pathogenesis, but recent investigations also revealed the involvement of non-genetic alterations in the disease development. In this study, we undertook a multi-omics approach, encompassing ATAC-seq, RNA-seq, ChIP-seq, and Hi-C methodologies, to dissect gene expression alterations arising from changes in chromosome accessibility and chromatin three-dimensional interactions in PDAC. RESULTS: Our findings indicate that chromosomal structural alterations can lead to abnormal expressions on key genes during PDAC development. Notably, overexpression of oncogenes FGFR2, FOXA2, CYP2R1, and CPOX can be attributed to the augmentation of promoter accessibility, coupled with long-range interactions with distal elements. Additionally, our findings indicate that chromosomal structural alterations caused by genomic instability can lead to abnormal expressions in PDACs. As an example, by analyzing chromosomal changes, we identified a putative oncogenic gene, LPAR1, which shows upregulated expression in both PDAC cell lines and clinical samples. The overexpression is correlated with alterations in LPAR1-associated 3D genome structure and chromatin state. We further demonstrated that high LPAR1 activity is required for enhanced PDAC cell migration in vitro. CONCLUSIONS: Collectively, our findings reveal that the chromosomal conformational alterations, in addition to the well-known genetic mutations, are critical for PDAC tumorigenesis.


Subject(s)
Carcinoma, Pancreatic Ductal , Pancreatic Neoplasms , Humans , Pancreatic Neoplasms/genetics , Pancreatic Neoplasms/pathology , Carcinoma, Pancreatic Ductal/genetics , Carcinogenesis/genetics , Gene Expression , Chromatin/genetics , Gene Expression Regulation, Neoplastic
10.
BMC Microbiol ; 24(1): 131, 2024 Apr 20.
Article in English | MEDLINE | ID: mdl-38643098

ABSTRACT

BACKGROUND: Exposure to extreme cold or heat temperature is one leading cause of weather-associated mortality and morbidity in animals. Emerging studies demonstrate that the microbiota residing in guts act as an integral factor required to modulate host tolerance to cold or heat exposure, but common and unique patterns of animal-temperature associations between cold and heat have not been simultaneously examined. Therefore, we attempted to investigate the roles of gut microbiota in modulating tolerance to cold or heat exposure in mice. RESULTS: The results showed that both cold and heat acutely change the body temperature of mice, but mice efficiently maintain their body temperature at conditions of chronic extreme temperatures. Mice adapt to extreme temperatures by adjusting body weight gain, food intake and energy harvest. Fascinatingly, 16 S rRNA sequencing shows that extreme temperatures result in a differential shift in the gut microbiota. Moreover, transplantation of the extreme-temperature microbiota is sufficient to enhance host tolerance to cold and heat, respectively. Metagenomic sequencing shows that the microbiota assists their hosts in resisting extreme temperatures through regulating the host insulin pathway. CONCLUSIONS: Our findings highlight that the microbiota is a key factor orchestrating the overall energy homeostasis under extreme temperatures, providing an insight into the interaction and coevolution of hosts and gut microbiota.


Subject(s)
Gastrointestinal Microbiome , Hot Temperature , Animals , Mice , Temperature , Gastrointestinal Microbiome/physiology , Cold Temperature , Adaptation, Physiological/physiology
11.
New Phytol ; 241(4): 1813-1828, 2024 Feb.
Article in English | MEDLINE | ID: mdl-38062896

ABSTRACT

Nodulation begins with the initiation of infection threads (ITs) in root hairs. Though mutual recognition and early symbiotic signaling cascades in legumes are well understood, molecular mechanisms underlying bacterial infection processes and successive nodule organogenesis remain largely unexplored. We functionally investigated a novel pectate lyase enzyme, GmNPLa, and its transcriptional regulator GmPTF1a/b in soybean (Glycine max), where their regulatory roles in IT development and nodule formation were elucidated through investigation of gene expression patterns, bioinformatics analysis, biochemical verification of genetic interactions, and observation of phenotypic impacts in transgenic soybean plants. GmNPLa was specifically induced by rhizobium inoculation in root hairs. Manipulation of GmNPLa produced remarkable effects on IT and nodule formation. GmPTF1a/b displayed similar expression patterns as GmNPLa, and manipulation of GmPTF1a/b also severely influenced nodulation traits. LI soybeans with low nodulation phenotypes were nearly restored to HI nodulation level by complementation of GmNPLa and/or GmPTF1a. Further genetic and biochemical analysis demonstrated that GmPTF1a can bind to the E-box motif to activate transcription of GmNPLa, and thereby facilitate nodulation. Taken together, our findings potentially reveal novel mediation of cell wall gene expression involving the basic helix-loop-helix transcription factor GmPTF1a/b acts as a key early regulator of nodulation in soybean.


Subject(s)
Glycine max , Rhizobium , Glycine max/genetics , Plant Root Nodulation/physiology , Plant Proteins/metabolism , Rhizobium/physiology , Phenotype , Gene Expression Regulation, Plant , Symbiosis
12.
Plant Cell Environ ; 47(4): 1041-1052, 2024 Apr.
Article in English | MEDLINE | ID: mdl-37997205

ABSTRACT

In arbuscular mycorrhizal (AM) symbiosis, sugars in root cortical cells could be exported as glucose or sucrose into peri-arbuscular space for use by AM fungi. However, no sugar transporter has been identified to be involved in sucrose export. An AM-inducible SWEET transporter, GmSWEET6, was functionally characterised in soybean, and its role in AM symbiosis was investigated via transgenic plants. The expression of GmSWEET6 was enhanced by inoculation with the cooperative fungal strain in both leaves and roots. Heterologous expression in a yeast mutant showed that GmSWEET6 mainly transported sucrose. Transgenic plants overexpressing GmSWEET6 increased sucrose concentration in root exudates. Overexpression or knockdown of GmSWEET6 decreased plant dry weight, P content, and sugar concentrations in non-mycorrhizal plants, which were partly recovered in mycorrhizal plants. Intriguingly, overexpression of GmSWEET6 increased root P content and decreased the percentage of degraded arbuscules, while knockdown of GmSWEET6 increased root sugar concentrations in RNAi2 plants and the percentage of degraded arbuscules in RNAi1 plants compared with wild-type plants when inoculated with AM fungi. These results in combination with subcellular localisation of GmSWEET6 to peri-arbuscular membranes strongly suggest that GmSWEET6 is required for AM symbiosis by mediating sucrose efflux towards fungi.


Subject(s)
Mycorrhizae , Symbiosis , Glycine max , Mycorrhizae/metabolism , Fungi , Plants, Genetically Modified/metabolism , Glucose/metabolism , Sucrose/metabolism , Plant Roots/metabolism
13.
Neurochem Res ; 49(7): 1720-1734, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38520637

ABSTRACT

Vascular dementia (VaD) has a serious impact on the patients' quality of life. Icariin (Ica) possesses neuroprotective potential for treating VaD, yet its oral bioavailability and blood-brain barrier (BBB) permeability remain challenges. This research introduced a PEG-PLGA-loaded chitosan hydrogel-based binary formulation tailored for intranasal delivery, enhancing the intracerebral delivery efficacy of neuroprotective agents. The formulation underwent optimization to facilitate BBB crossing, with examinations conducted on its particle size, morphology, drug-loading capacity, in vitro release, and biodistribution. Using the bilateral common carotid artery occlusion (BCCAO) rat model, the therapeutic efficacy of this binary formulation was assessed against chitosan hydrogel and PEG-PLGA nanoparticles loaded with Ica. Post-intranasal administration, enhanced cognitive function was evident in chronic cerebral hypoperfusion (CCH) rats. Further mechanistic evaluations, utilizing immunohistochemistry (IHC), RT-PCR, and ELISA, revealed augmented transcription of synaptic plasticity-associated proteins like SYP and PSD-95, and a marked reduction in hippocampal inflammatory markers such as IL-1ß and TNF-α, highlighting the formulation's promise in alleviating cognitive impairment. The brain-derived neurotrophic factor (BDNF)/tropomyosin related kinase B (TrkB) pathway was activated significantly in the binary formulation compared with the other two. Our study demonstrates that the intranasal application of chitosan hydrogel loaded with Ica-encapsulated PEG-PLGA could effectively deliver Ica into the brain and enhance its neuroprotective effect.


Subject(s)
Brain-Derived Neurotrophic Factor , Dementia, Vascular , Flavonoids , Rats, Sprague-Dawley , Receptor, trkB , Signal Transduction , Animals , Flavonoids/pharmacology , Flavonoids/administration & dosage , Flavonoids/therapeutic use , Dementia, Vascular/drug therapy , Dementia, Vascular/metabolism , Male , Brain-Derived Neurotrophic Factor/metabolism , Receptor, trkB/metabolism , Signal Transduction/drug effects , Anti-Inflammatory Agents/administration & dosage , Anti-Inflammatory Agents/pharmacology , Anti-Inflammatory Agents/therapeutic use , Cognition/drug effects , Nanoparticles/chemistry , Neuroprotective Agents/administration & dosage , Neuroprotective Agents/therapeutic use , Neuroprotective Agents/pharmacology , Rats , Polyethylene Glycols/chemistry , Chitosan/chemistry , Administration, Intranasal , Nanoparticle Drug Delivery System , Polyesters
14.
Article in English | MEDLINE | ID: mdl-38194256

ABSTRACT

Two novel halophilic archaeal strains (XZGYJ-43T and ZJ1T) were isolated from Mangkang ancient solar saltern (Tibet, PR China) and Zhujiang river inlet (Guangdong, PR China), respectively. The comparison of the 16S rRNA gene sequences revealed that strain XZGYJ-43T is related to the current species of the family Halobacteriaceae (89.2-91.7% similarity) and strain ZJ1T showed 94.7-98.3% similarity to the current species of the genus Haladaptatus. Phylogenetic analyses based on 16S rRNA genes, rpoB' genes and genomes indicated that strain XZGYJ-43T is separate from the related genera, Halocalculus, Salarchaeum and Halarchaeum of the family Halobacteriaceae, and strain ZJ1T tightly clusters with the current species of the genus Haladaptatus. The average nucleotide identity, digital DNA-DNA hybridization and average amino acid identity values between strain XZGYJ-43T and the current species of the family Halobacteriaceae were 71-75, 20-25 and 59-68 %, and these values between strain ZJ1T and the current species of the genus Haladaptatus were 77-81, 27-32 and 76-82 %, respectively, clearly below the thresholds for prokaryotic species demarcation. These two strains could be distinguished from their relatives according to differential phenotypic characteristics. The major polar lipids of strain XZGYJ-43T were phosphatidic acid (PA), phosphatidylglycerol (PG), phosphatidylglycerol phosphate methyl ester (PGP-Me), mannosyl glucosyl diether (DGD-1; DGD-PA) and sulphated mannosyl glucosyl diether (S-DGD-1; S-DGD-PA), and those of strain ZJ1T were PA, PG, PGP-Me, DGD-PA, S-DGD-1 (S-DGD-PA) and sulphated galactosyl mannosyl glucosyl diether. Based on phenotypic, phylogenetic and genomic data, strain XZGYJ-43T (=CGMCC 1.13890T=JCM 33735T) represents a novel species of a new genus within the family Halobacteriaceae, and strain ZJ1T (=CGMCC 1.18785T=JCM 34917T) represents a novel species of the genus Haladaptatus, for which the names Halospeciosus flavus gen. nov., sp. nov. and Haladaptatus caseinilyticus sp. nov. are proposed, respectively.


Subject(s)
Halobacteriaceae , Halobacteriales , Phylogeny , RNA, Ribosomal, 16S/genetics , Sequence Analysis, DNA , DNA, Bacterial/genetics , Bacterial Typing Techniques , Base Composition , Fatty Acids/chemistry , Halobacteriaceae/genetics , Phosphatidylglycerols
15.
Article in English | MEDLINE | ID: mdl-38197785

ABSTRACT

Two extremely halophilic archaeal strains, GSLN9T and XZYJT29T, were isolated from the saline soil in different regions of western China. Both strains GSLN9T and XZYJT29T have two 16S rRNA genes with similarities of 95.1 and 94.8 %, respectively. Strain GSLN9T was mostly related to the genus Halomicrococcus based on 16S rRNA (showing 91.0-96.0 % identities) and rpoB' genes (showing 92.0 % identity). Strain XZYJT29T showed 92.1-97.6 % (16S rRNA gene) and 91.4-93.1 % (rpoB' gene) sequence similarities to its relatives in the genus Halosimplex, respectively. The polar lipid profile of strain GSLN9T included phosphatidic acid (PA), phosphatidylglycerol (PG), phosphatidylglycerol phosphate methyl ester (PGP-Me), phosphatidylglycerol sulphate (PGS), sulphated mannosyl glucosyl diether (S-DGD-1) and sulphated galactosyl mannosyl glucosyl diether (S-TGD-1), mostly similar to that of Halomicrococcus hydrotolerans H22T. PA, PG, PGP-Me, S-DGD-1 (S-DGD-PA), S2-DGD, S-TGD-1 and an unidentified glycolipid were detected in strain XZYJT29T; this polar lipid composition is similar to those of members of the genus Halosimplex. The average nucleotide identity, digital DNA-DNA hybridization and average amino acid identity values between these two strains and their relatives of the genera Halomicrococcus and Halosimplex were no more than 82, 27 and 80 %, respectively, much lower than the thresholds for species demarcation. Other phenotypic characterization results indicated that strains GSLN9T and XZYJT29T can be differentiated from the current species of the genera Halomicrococcus and Halosimplex, respectively. These results revealed that strains GSLN9T (=CGMCC 1.15215T=JCM 30842T) and XZYJT29T (=CGMCC 1.15828T=JCM 31853T) represent novel species of Halomicrococcus and Halosimplex, for which the names Halomicrococcus gelatinilyticus sp. nov. and Halosimplex aquaticum sp. nov. are proposed.


Subject(s)
Halobacteriaceae , Halobacteriales , RNA, Ribosomal, 16S/genetics , Phylogeny , Sequence Analysis, DNA , DNA, Bacterial/genetics , Bacterial Typing Techniques , Base Composition , Fatty Acids/chemistry , Halobacteriaceae/genetics , Phosphatidylglycerols , Soil , Sulfates
16.
Extremophiles ; 28(1): 10, 2024 Jan 12.
Article in English | MEDLINE | ID: mdl-38214762

ABSTRACT

The genera Haloarcula and Halomicroarcula are the most closely related genera within the family Haloarculaceae (class Halobacteria). The respective 16S rRNA genes of type strains from the genus Haloarcula showed 94.7-96.5% similarities to their homologous genes of type strains from the genus Halomicroarcula. The Haloarcula species showed 89.3-92.8% rpoB' gene similarities to Halomicroarcula species. These similarities were higher than the proposed genus boundary. Phylogenomic analysis revealed that these two genera formed a tight cluster separated from Halomicrobium with high bootstrap confidence. The average amino acid identity (AAI) values among Haloarcula and Halomicroarcula were 70.1-74.5%, higher than the cutoff value (67.0%) to differentiate the genera Haloarcula and Halomicroarcula from Halomicrobium. These results indicated that the genus Halomicroarcula should be merged with Haloarcula. Then, six novel species are described based on strains DFY41T, GDY20T, SHR3T, XH51T, YJ-61-ST, and ZS-22-S1T isolated from coarse sea salt, marine solar saltern, and salt lake (China). These six strains formed separate clades (90.1-99.3% 16S rRNA and 89.0-94.9% rpoB' gene similarities) and then clustered with current Haloarcula and Halomicroarcula species (89.4-99.1% 16S rRNA and 87.6-95.0% rpoB' gene similarities), as revealed by phylogenetic analyses. The average nucleotide identity (ANI), digital DNA-DNA hybridization (dDDH), and AAI values among these six strains and current Haloarcula and Halomicroarcula species were 76.2-89.8%, 25.3-46.0%, and 70.3-89.7%, respectively, clearly below the species demarcation threshold. These six strains were distinguished from current Haloarcula and Halomicroarcula species according to differential phenotypic characteristics. Six novel species, Haloarcula halophila sp. nov., Haloarcula litorea sp. nov., Haloarcula rara sp. nov., Haloarcula halobia sp. nov., Haloarcula pelagica sp. nov., and Haloarcula ordinaria sp. nov., are proposed to accommodate strains DFY41T, GDY20T, SHR3T, XH51T, YJ-61-ST, and ZS-22-S1T, respectively.


Subject(s)
Haloarcula , Halobacteriaceae , Halobacteriales , Phylogeny , RNA, Ribosomal, 16S/genetics , DNA, Archaeal/genetics , Base Composition , Sequence Analysis, DNA , Fatty Acids/chemistry , DNA, Bacterial , Bacterial Typing Techniques
17.
Extremophiles ; 28(2): 28, 2024 Jun 18.
Article in English | MEDLINE | ID: mdl-38890178

ABSTRACT

Four halophilic archaeal strains YCN1T, YCN58T, LT38T, and LT62T were isolated from Yuncheng Salt Lake (Shanxi, China) and Tarim Basin (Xinjiang, China), respectively. Phylogenetic and phylogenomic analyses showed that these four strains tightly cluster with related species of Halobacterium, Natronomonas, Halorientalis, and Halobellus, respectively. The AAI, ANI, and dDDH values between these four strains and their related species of respective genera were lower than the proposed threshold values for species delineation. Strains YCN1T, YCN58T, LT38T, and LT62T could be differentiated from the current species of Halobacterium, Natronomonas, Halorientalis, and Halobellus, respectively, based on the comparison of diverse phenotypic characteristics. The polar lipid profiles of these four strains were closely similar to those of respective relatives within the genera Halobacterium, Natronomonas, Halorientalis, and Halobellus, respectively. The phenotypic, phylogenetic, and genome-based analyses indicated that strains YCN1T, YCN58T, LT38T, and LT62T represent respective novel species within the genera Halobacterium, Natronomonas, Halorentalis, and Halobellus, for which the names Halobacterium yunchengense sp. nov., Natronomonas amylolytica sp. nov., Halorientalis halophila sp. nov., and Halobellus salinisoli sp. nov. are proposed, respectively.


Subject(s)
Lakes , Phylogeny , Lakes/microbiology , Soil Microbiology , Halobacterium/genetics , Halobacterium/isolation & purification , Genome, Archaeal , Halobacteriaceae/genetics , Halobacteriaceae/isolation & purification , Halobacteriaceae/classification
18.
Analyst ; 149(4): 1074-1080, 2024 Feb 12.
Article in English | MEDLINE | ID: mdl-37955046

ABSTRACT

Breath analysis may provide a convenient and non-invasive method for clinical monitoring of chronic kidney disease (CKD) progression. However, few breath volatile organic compounds (VOCs) indicating progression of CKD have been reported. In this study, we used gas chromatography-mass spectrometry (GC-MS) for untargeted detection of breath VOCs in stage 1, 3, and 5 CKD patients. The results showed that, the levels of breath 4-heptanone, n-octane, and n-dodecane gradually increased from CKD stage 1 to stage 5, and their increasing rates from CKD stage 3 to stage 5 were higher than those from CKD stage 1 to stage 3. Gender, smoking habits, age, and body mass index (BMI) had insignificant impact on the levels of the three breath VOCs. The accuracies of the polynomial support vector machine (SVM) and K-nearest neighbour (KNN) models based on 4-heptanone + n-octane + n-dodecane combination in distinguishing CKD stages 1, 3, and 5 were 76.3% and 72.8%, respectively. The combination of 4-heptanone + n-octane + n-dodecane was superior to any single component for monitoring CKD progression. These discoveries have valuable implications for long-term clinical monitoring of CKD and improving our understanding of CKD.


Subject(s)
Alkanes , Ketones , Octanes , Renal Insufficiency, Chronic , Volatile Organic Compounds , Humans , Volatile Organic Compounds/analysis , Renal Insufficiency, Chronic/diagnosis , Breath Tests/methods
19.
Analyst ; 149(7): 2103-2113, 2024 Mar 25.
Article in English | MEDLINE | ID: mdl-38421308

ABSTRACT

The surface modification technique is applied in microfluidic devices to modify wettability and achieve different flow velocities. Currently available methods for poly(dimethylsiloxane) (PDMS) surfaces may reliably induce wettability changes, but only one area can be altered at a time. This work introduces the controlled gradient oxygen plasma modification (CGPM) technique, which layers several resin masks with varying porosities on top of the PDMS surface. Selective wettability of the PDMS surface can be achieved by varying the oxygen plasma density above the modified material's surface by manipulation of the porosity value. Through the implementation of the COMSOL plasma module, the impact of the mask's porosity, through-hole size, distribution, and distance from the PDMS surface on wettability was studied. The suggested CGPM approach was characterized by contact angle measurements. During the 25-second CGPM procedure, the PDMS surface's contact angle continually changed from 8.77° to 76.98°. An integrated microfluidic device was created and manufactured to identify D-dimers to illustrate this method. In comparison with standard oxygen plasma treatment, the D-dimer assay was finished in 10 minutes and had a dynamic range of 1-1000 ng mL-1, with a peak fluorescence signal augmentation of 78.3% and an average fluorescence intensity enhancement of 31.1%.

20.
Environ Sci Technol ; 2024 Jul 02.
Article in English | MEDLINE | ID: mdl-38956968

ABSTRACT

Elevated levels of atmospheric molecular chlorine (Cl2) have been observed during the daytime in recent field studies in China but could not be explained by the current chlorine chemistry mechanisms in models. Here, we propose a Cl2 formation mechanism initiated by aerosol iron photochemistry to explain daytime Cl2 formation. We implement this mechanism into the GEOS-Chem chemical transport model and investigate its impacts on the atmospheric composition in wintertime North China where high levels of Cl2 as well as aerosol chloride and iron were observed. The new mechanism accounts for more than 90% of surface air Cl2 production in North China and consequently increases the surface air Cl2 abundances by an order of magnitude, improving the model's agreement with observed Cl2. The presence of high Cl2 significantly alters the oxidative capacity of the atmosphere, with a factor of 20-40 increase in the chlorine radical concentration and a 20-40% increase in the hydroxyl radical concentration in regions with high aerosol chloride and iron loadings. This results in an increase in surface air ozone by about 10%. This new Cl2 formation mechanism will improve the model simulation capability for reactive chlorine abundances in the regions with high emissions of chlorine and iron.

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