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1.
Nucleic Acids Res ; 51(D1): D603-D610, 2023 01 06.
Artigo em Inglês | MEDLINE | ID: mdl-36399496

RESUMO

With an ever-increasing amount of (meta)genomic data being deposited in sequence databases, (meta)genome mining for natural product biosynthetic pathways occupies a critical role in the discovery of novel pharmaceutical drugs, crop protection agents and biomaterials. The genes that encode these pathways are often organised into biosynthetic gene clusters (BGCs). In 2015, we defined the Minimum Information about a Biosynthetic Gene cluster (MIBiG): a standardised data format that describes the minimally required information to uniquely characterise a BGC. We simultaneously constructed an accompanying online database of BGCs, which has since been widely used by the community as a reference dataset for BGCs and was expanded to 2021 entries in 2019 (MIBiG 2.0). Here, we describe MIBiG 3.0, a database update comprising large-scale validation and re-annotation of existing entries and 661 new entries. Particular attention was paid to the annotation of compound structures and biological activities, as well as protein domain selectivities. Together, these new features keep the database up-to-date, and will provide new opportunities for the scientific community to use its freely available data, e.g. for the training of new machine learning models to predict sequence-structure-function relationships for diverse natural products. MIBiG 3.0 is accessible online at https://mibig.secondarymetabolites.org/.


Assuntos
Genoma , Genômica , Família Multigênica , Vias Biossintéticas/genética
2.
Environ Microbiol ; 26(2): e16589, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38356049

RESUMO

Ancient environmental samples, including permafrost soils and frozen animal remains, represent an archive with microbial communities that have barely been explored. This yet unexplored microbial world is a genetic resource that may provide us with new evolutionary insights into recent genomic changes, as well as novel metabolic pathways and chemistry. Here, we describe Actinomycetota Micromonospora, Oerskovia, Saccharopolyspora, Sanguibacter and Streptomyces species were successfully revived and their genome sequences resolved. Surprisingly, the genomes of these bacteria from an ancient source show a large phylogenetic distance to known strains and harbour many novel biosynthetic gene clusters that may well represent uncharacterised biosynthetic potential. Metabolic profiles of the strains display the production of known molecules like antimycin, conglobatin and macrotetrolides, but the majority of the mass features could not be dereplicated. Our work provides insights into Actinomycetota isolated from an ancient source, yielding unexplored genomic information that is not yet present in current databases.


Assuntos
Actinomycetales , Mamutes , Streptomyces , Animais , Filogenia , Genômica , Streptomyces/genética , Fezes
3.
Appl Environ Microbiol ; 90(4): e0208723, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38557137

RESUMO

Filamentous growth of streptomycetes coincides with the synthesis and deposition of an uncharacterized protective glucan at hyphal tips. Synthesis of this glucan depends on the integral membrane protein CslA and the radical copper oxidase GlxA, which are part of a presumably large multiprotein complex operating at growing tips. Here, we show that CslA and GlxA interact by forming a protein complex that is sufficient to synthesize cellulose in vitro. Mass spectrometry analysis revealed that the purified complex produces cellulose chains with a degree of polymerization of at least 80 residues. Truncation analyses demonstrated that the removal of a significant extracellular segment of GlxA had no impact on complex formation, but significantly diminished activity of CslA. Altogether, our work demonstrates that CslA and GlxA form the active core of the cellulose synthase complex and provide molecular insights into a unique cellulose biosynthesis system that is conserved in streptomycetes. IMPORTANCE: Cellulose stands out as the most abundant polysaccharide on Earth. While the synthesis of this polysaccharide has been extensively studied in plants and Gram-negative bacteria, the mechanisms in Gram-positive bacteria have remained largely unknown. Our research unveils a novel cellulose synthase complex formed by the interaction between the cellulose synthase-like protein CslA and the radical copper oxidase GlxA from Streptomyces lividans, a soil-dwelling Gram-positive bacterium. This discovery provides molecular insights into the distinctive cellulose biosynthesis machinery. Beyond expanding our understanding of cellulose biosynthesis, this study also opens avenues for exploring biotechnological applications and ecological roles of cellulose in Gram-positive bacteria, thereby contributing to the broader field of microbial cellulose biosynthesis and biofilm research.


Assuntos
Polissacarídeos , Streptomyces lividans , Streptomyces lividans/genética , Streptomyces lividans/metabolismo , Polissacarídeos/metabolismo , Glucosiltransferases/genética , Glucosiltransferases/metabolismo , Celulose/metabolismo
4.
Opt Lett ; 49(13): 3677, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38950239

RESUMO

This publisher's note contains a correction to Opt. Lett.48, 3219 (2023)10.1364/OL.486644.

5.
Med Vet Entomol ; 38(1): 59-72, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37771128

RESUMO

Pederin, a defensive toxin in Paederus fuscipes, is produced by an uncultured Gram-negative symbiont, which establishes a stable symbiotic relationship with a female host before completion of metamorphosis. However, the transmission process of pederin-producing bacteria (PPB) in P. fuscipes at different life stages remains unknown. Herein, the PPB population dynamics and transcriptome atlas for P. fuscipes development (egg, first-instar larva, second-instar larva, pupa, and newly emerged female and male) were characterised. We found that a microbial layer containing PPB covered the eggshell, which could be sterilised by smearing the eggshell with streptomycin. Maternal secretions over the eggshell are likely the main PPB acquisition route for P. fuscipes offspring. The PPB density in eggs was significantly higher than that in other life stages (p < 0.05), which demonstrated that the beetle mothers gave more PPB than the larvae acquired. Physiological changes (hatching and eclosion) led to a decreased PPB density in P. fuscipes. Pattern recognition receptors related to Gram-negative bacteria recognition were identified from P. fuscipes transcriptomes across various life stages, which might be used to screen genes involved in PPB regulation. These results will help advance future efforts to determine the molecular mechanisms of PPB colonisation of P. fuscipes.


Assuntos
Besouros , Masculino , Feminino , Animais , Besouros/microbiologia , Besouros/fisiologia , Bactérias/genética , Larva , Piranos
6.
Neurol Sci ; 45(4): 1523-1527, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37904013

RESUMO

BACKGROUND: Amyotrophic lateral sclerosis (ALS) is a progressive neurodegenerative disease that is now recognized to involve autonomic dysfunction. The burden of autonomic dysfunction is an important factor in the quality of life and prognosis of ALS patients. This article presents the clinical characteristics of a young female ALS patient with a fused in sarcoma (FUS) gene mutation and notable hyperhidrosis. METHOD: Detailed clinical characteristics of the patients were collected, and comprehensive examinations such as electrophysiological assessment, neuro-ultrasound, genetic testing, and relevant blood tests were conducted. RESULT: A 24-year-old female experienced progressive weakness in both lower limbs for over 5 months, along with excessive sweating on both palms and feet. A positive skin iodine-starch test was observed. Electromyography revealed extensive neurogenic damage and prolonged sympathetic skin response (SSR) latency in both lower limbs. Full exon gene sequencing showed a heterozygous mutation c.1574C>T (p.Pro525Leu) in the FUS gene. CONCLUSION: The pathogenesis of ALS remains unclear at present. This case underscores the presence of autonomic nervous symptoms in ALS associated with FUS mutation and highlights the importance of early diagnosis and timely treatment intervention to enhance patient prognosis.


Assuntos
Esclerose Lateral Amiotrófica , Hiperidrose , Doenças Neurodegenerativas , Feminino , Humanos , Adulto Jovem , Esclerose Lateral Amiotrófica/complicações , Esclerose Lateral Amiotrófica/diagnóstico , Esclerose Lateral Amiotrófica/genética , Hiperidrose/genética , Mutação , Qualidade de Vida , Proteína FUS de Ligação a RNA/genética
7.
BMC Pulm Med ; 24(1): 12, 2024 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-38178046

RESUMO

BACKGROUND: The new coronavirus Omicron variant strain spread rapidly worldwide and is currently the primary mutant strain prevalent in the world. OBJECTIVE: To explore the clinical features of severe central nervous system lesions in children infected with novel coronavirus Omicron mutant strain, so as to provide a reference for clinical diagnosis and treatment. MATERIALS AND METHODS: The clinical data of 13 children diagnosed with novel coronavirus Omicron variant strain complicated with severe central nervous system infection from December 13, 2022, to January 31, 2023, in the Children's Intensive Care Medicine Department of Shanxi Children's Hospital were retrospectively analyzed. RESULTS: Among the 13 children, there were 9 males (69%) and 4 females (31%); the ages ranged from 1-year-old 16 days to 13 years old, with a median age of 9 years old, and most of them were school-age children (84.6%). The 13 children were usually healthy, but this time they were all positive for the new coronavirus nucleic acid test. The 13 children had obvious signs of the abnormal nervous system when they were admitted to the hospital, among which 12 cases (92.3%) showed convulsions, 11 children had obvious disturbance of consciousness (84.6%) when they were admitted to the hospital, and 5 children had circulatory disorders (38.4%). Among the 13 children, 2 were cured (15.3%), 5 children had serious sequelae (38.4%) when they were discharged from the hospital, and 6 children died of severe illness (46.3%). CONCLUSION: This study illuminates the clinical characteristics of severe central nervous system complications in children with coronavirus variant infection, highlighting rapid onset, swift progression, relatively poor prognosis, and notable symptoms such as high fever, convulsions, altered consciousness, elevated interleukin-6 levels, increased cerebrospinal fluid lactate levels, and early imaging changes.


Assuntos
Sistema Nervoso Central , SARS-CoV-2 , Criança , Masculino , Feminino , Humanos , Recém-Nascido , Estudos Retrospectivos , Convulsões , Hospitais
8.
Int J Mol Sci ; 25(7)2024 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-38612689

RESUMO

Intestinal epithelial cells (IECs) play crucial roles in forming an essential barrier, providing host defense against pathogens and regulating nutrients absorption. Milk-derived extracellular vesicles (EVs) within its miRNAs are capable of modulating the recipient cell function. However, the differences between colostrum and mature milk EVs and their biological function in attenuating intestinal epithelial cell injury remain poorly understood. Thus, we carried out the present study to characterize the difference between colostrum and mature milk-derived miRNA of EVs and the effect of colostrum and mature milk EVs on the proliferation, apoptosis, proinflammatory cytokines and intestinal epithelial barrier related genes in IEC-6 induced by LPS. Differential expression of 329 miRNAs was identified between colostrum and mature milk EVs, with 185 miRNAs being downregulated and 144 upregulated. In addition, colostrum contains a greater number and protein concentration of EVs than mature milk. Furthermore, compared to control, EVs derived from colostrum significantly inhibited the expression of apoptosis- (Bax, p53, and caspase-3) and proinflammatory-related genes (TNFα, IL6, and IL1ß). EVs derived from mature milk did not affect expression of apoptosis-related genes (Bax, p53, bcl2, and caspase-3). The EVs derived from mature milk significantly inhibited the expression of proinflammatory-related genes (TNFα and IL6). Western blot analysis also indicated that colostrum and mature milk EVs significantly decreased the apoptosis of IEC-6 cells. The EdU assay results showed that colostrum and mature milk EVs significantly increased the proliferation of IEC-6 cells. The expression of intestinal barrier-related genes (TJP1, CLDN1, OCLN, CDX2, MUC2, and IGF1R) was significantly promoted in IEC-6 cells after colostrum and mature milk EVs addition. Importantly, colostrum and mature milk EVs significantly relieved the LPS-induced inhibition of proliferation and intestinal barrier-related genes expression and attenuated apoptosis and proinflammatory responses induced by LPS in IEC-6 cells. Flow cytometry and Western blot analysis also indicated that colostrum and mature milk EVs significantly affect the apoptosis of IEC-6 cells induced by LPS. The results also indicated that EVs derived from colostrum had better effects on inhibiting the apoptosis- and proinflammatory cytokines-related genes expression. However, the EVs derived from mature milk exhibited beneficial effects on intestinal epithelial barrier protection. The present study will provide a better understanding of the role of EVs derived from colostrum and milk in dairy cows with different responses in the regulation of intestinal cells function, and also presents new evidence for the change of EVs cargos during various stages of lactation.


Assuntos
Vesículas Extracelulares , Leite , Animais , Feminino , Gravidez , Bovinos , Colostro , Lipopolissacarídeos/farmacologia , Caspase 3 , Fator de Necrose Tumoral alfa , Interleucina-6 , Proteína Supressora de Tumor p53 , Proteína X Associada a bcl-2 , Células Epiteliais
9.
Appl Environ Microbiol ; 89(12): e0167423, 2023 12 21.
Artigo em Inglês | MEDLINE | ID: mdl-37982622

RESUMO

IMPORTANCE: Central metabolism plays a key role in the control of growth and antibiotic production in streptomycetes. Specifically, aminosugars act as signaling molecules that affect development and antibiotic production, via metabolic interference with the global repressor DasR. While aminosugar metabolism directly connects to other major metabolic routes such as glycolysis and cell wall synthesis, several important aspects of their metabolism are yet unresolved. Accumulation of N-acetylglucosamine 6-phosphate or glucosamine 6-phosphate is lethal to many bacteria, a yet unresolved phenomenon referred to as "aminosugar sensitivity." We made use of this concept by selecting for suppressors in genes related to glucosamine toxicity in nagB mutants, which showed that the gene pair of rok-family regulatory gene rokL6 and major facilitator superfamily transporter gene sco1448 forms a cryptic rescue mechanism. Inactivation of rokL6 resulted in the expression of sco1448, which then prevents the toxicity of amino sugar-derived metabolites in Streptomyces. The systems biology of RokL6 and its transcriptional control of sco1448 shed new light on aminosugar metabolism in streptomycetes and on the response of bacteria to aminosugar toxicity.


Assuntos
Streptomyces coelicolor , Streptomyces , Streptomyces coelicolor/genética , Streptomyces coelicolor/metabolismo , Glucosamina/metabolismo , Streptomyces/genética , Amino Açúcares/metabolismo , Antibacterianos , Genes Reguladores , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Regulação Bacteriana da Expressão Gênica
10.
Appl Environ Microbiol ; 89(11): e0123923, 2023 11 29.
Artigo em Inglês | MEDLINE | ID: mdl-37902333

RESUMO

IMPORTANCE: Microorganisms that live on or inside plants can influence plant growth and health. Among the plant-associated bacteria, streptomycetes play an important role in defense against plant diseases, but the underlying mechanisms are not well understood. Here, we demonstrate that the plant hormones jasmonic acid (JA) and methyl jasmonate directly affect the life cycle of streptomycetes by modulating antibiotic synthesis and promoting faster development. Moreover, the plant hormones specifically stimulate the synthesis of the polyketide antibiotic actinorhodin in Streptomyces coelicolor. JA is then modified in the cell by amino acid conjugation, thereby quenching toxicity. Collectively, these results provide new insight into the impact of a key plant hormone on diverse phenotypic responses of streptomycetes.


Assuntos
Aminoácidos , Reguladores de Crescimento de Plantas , Antibacterianos , Hormônios
11.
Opt Lett ; 48(17): 4540-4543, 2023 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-37656548

RESUMO

We demonstrated a long-range and centimeter-spatial-resolution optical frequency domain reflectometry (OFDR) system based on an ultra-linear broadband optical frequency sweep. The high nonlinear sweeping effect of the distributed feedback (DFB) diode laser was suppressed by a pre-distortion method, ensuring that the injection-locking process remained stable during fast tuning over a large span. An optical linear frequency sweep (LFS) with a sweep range and sweep rate of up to 60 GHz and 15 THz/s, respectively, was ultimately obtained by optimizing the injection-locking system. The high performance OFDR based on the proposed LFS achieved a sampling spatial resolution of 1.71 mm. Furthermore, distributed strain sensing was implemented with high-spatial resolutions of about 5 cm and 7 cm in the measurement range over 1 km and 2 km, respectively.

12.
Opt Lett ; 48(12): 3219-3222, 2023 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-37319066

RESUMO

An optical fiber φ-OFDR shape sensor with a submillimeter spatial resolution of 200 µm was demonstrated by using femtosecond-laser-induced permanent scatter array (PS array) multicore fiber (MCF). A PS array was successfully inscribed in each slightly twisted core of the 400-mm-long MCF. The two-dimensional (2D) and three-dimensional (3D) shapes of the PS-array-inscribed MCF were successfully reconstructed by using PS-assisted φ-OFDR, vector projections, and the Bishop frame based on the PS-array-inscribed MCF. The minimum reconstruction error per unit length of the 2D and 3D shape sensor was 2.21% and 1.45%, respectively.

13.
Eur J Nucl Med Mol Imaging ; 50(9): 2846-2860, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37097443

RESUMO

PURPOSE: Evans blue as an albumin binder has been widely used to improve pharmacokinetics and enhance tumor uptake of radioligands, including prostate-specific membrane antigen (PSMA) targeting agents. The goal of this study is to develop an optimal Evans blue-modified radiotherapeutic agent that could maximize the absolute tumor uptake and tumor absorbed dose thus the therapeutic efficacy to allow treatment of tumors even with moderate level of PSMA expression. METHODS: [177Lu]Lu-LNC1003 was synthesized based on PSMA-targeting agent and Evans blue. Binding affinity and PSMA targeting specificity were verified through cell uptake and competition binding assay in 22Rv1 tumor model that has moderate level of PSMA expression. SPECT/CT imaging and biodistribution studies in 22Rv1 tumor-bearing mice were performed to evaluate the preclinical pharmacokinetics. Radioligand therapy studies were conducted to systematically assess the therapeutic effect of [177Lu]Lu-LNC1003. RESULTS: LNC1003 showed high binding affinity (IC50 = 10.77 nM) to PSMA in vitro, which was comparable with that of PSMA-617 (IC50 = 27.49 nM) and EB-PSMA-617 (IC50 = 7.91 nM). SPECT imaging of [177Lu]Lu-LNC1003 demonstrated significantly improved tumor uptake and retention as compared with [177Lu]Lu-EB-PSMA and [177Lu]Lu-PSMA-617, making it suitable for prostate cancer therapy. Biodistribution studies further confirmed the remarkably higher tumor uptake of [177Lu]Lu-LNC1003 (138.87 ± 26.53%ID/g) over [177Lu]Lu-EB-PSMA-617 (29.89 ± 8.86%ID/g) and [177Lu]Lu-PSMA-617 (4.28 ± 0.25%ID/g) at 24 h post-injection. Targeted radioligand therapy results showed noteworthy inhibition of 22Rv1 tumor growth after administration of a single dose of 18.5 MBq [177Lu]Lu-LNC1003. There was no obvious antitumor effect after [177Lu]Lu-PSMA-617 treatment under the same condition. CONCLUSION: In this study, [177Lu]Lu-LNC1003 was successfully synthesized with high radiochemical purity and stability. High binding affinity and PSMA targeting specificity were identified in vitro and in vivo. With greatly enhanced tumor uptake and retention, [177Lu]Lu-LNC1003 has the potential to improve therapeutic efficacy using significantly lower dosages and less cycles of 177Lu that promises clinical translation to treat prostate cancer with various levels of PSMA expression.


Assuntos
Glutamato Carboxipeptidase II , Neoplasias da Próstata , Masculino , Humanos , Animais , Camundongos , Distribuição Tecidual , Azul Evans/uso terapêutico , Glutamato Carboxipeptidase II/metabolismo , Antígenos de Superfície/metabolismo , Neoplasias da Próstata/metabolismo , Compostos Radiofarmacêuticos/farmacocinética , Tomografia Computadorizada com Tomografia Computadorizada de Emissão de Fóton Único/métodos , Linhagem Celular Tumoral , Lutécio/uso terapêutico , Lutécio/farmacocinética
14.
Mol Pharm ; 20(10): 5185-5194, 2023 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-37711135

RESUMO

Ferroptosis, an iron-dependent regulated cell death, has been emerging as an early mechanism in anticancer drug-induced acute kidney injury (AKI) that may benefit therapeutic intervention. However, the lack of molecular imaging methods for in vivo detection of ferroptosis restricts the early diagnosis of anticancer drug-induced AKI. Herein, we developed a PET/19F MRI dual-modal imaging probe for the monitoring of ferroptosis in AKI by chemically conjugating the Fe(II)-sensitive artemisinin (Art) motif and macrocyclic ligand 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA) to the CF3-modified polyhedral oligomeric silsesquioxane (POSS) clusters, denoted as the PAD probe. The PAD probe could be converted into PA*D in the presence of Fe(II) ions and subsequently be intercepted by biological macromolecules nearby, thereby enhancing the retention effect in ferroptotic cells and tissues. After labeling with 68Ga isotopes, the 68Ga-labeled PAD probe in cisplatin (CDDP)-induced AKI mice displayed a significantly higher renal uptake level than that in normal mice. Moreover, the PAD probe with a precise chemical structure, relatively high 19F content, and single 19F resonance frequency allowed for interference-free and high-performance19F MRI that could detect the onset of CDDP-induced AKI at least 24 h earlier than the typical clinical/preclinical assays. Our study provides a robust dual-modal molecular imaging tool for the early diagnosis and mechanistic investigation of various ferroptosis-related diseases.

15.
PLoS Biol ; 18(12): e3001026, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33351797

RESUMO

Microbial natural products constitute a wide variety of chemical compounds, many which can have antibiotic, antiviral, or anticancer properties that make them interesting for clinical purposes. Natural product classes include polyketides (PKs), nonribosomal peptides (NRPs), and ribosomally synthesized and post-translationally modified peptides (RiPPs). While variants of biosynthetic gene clusters (BGCs) for known classes of natural products are easy to identify in genome sequences, BGCs for new compound classes escape attention. In particular, evidence is accumulating that for RiPPs, subclasses known thus far may only represent the tip of an iceberg. Here, we present decRiPPter (Data-driven Exploratory Class-independent RiPP TrackER), a RiPP genome mining algorithm aimed at the discovery of novel RiPP classes. DecRiPPter combines a Support Vector Machine (SVM) that identifies candidate RiPP precursors with pan-genomic analyses to identify which of these are encoded within operon-like structures that are part of the accessory genome of a genus. Subsequently, it prioritizes such regions based on the presence of new enzymology and based on patterns of gene cluster and precursor peptide conservation across species. We then applied decRiPPter to mine 1,295 Streptomyces genomes, which led to the identification of 42 new candidate RiPP families that could not be found by existing programs. One of these was studied further and elucidated as a representative of a novel subfamily of lanthipeptides, which we designate class V. The 2D structure of the new RiPP, which we name pristinin A3 (1), was solved using nuclear magnetic resonance (NMR), tandem mass spectrometry (MS/MS) data, and chemical labeling. Two previously unidentified modifying enzymes are proposed to create the hallmark lanthionine bridges. Taken together, our work highlights how novel natural product families can be discovered by methods going beyond sequence similarity searches to integrate multiple pathway discovery criteria.


Assuntos
Bacteriocinas/genética , Genômica/métodos , Processamento de Proteína Pós-Traducional/genética , Algoritmos , Bacteriocinas/metabolismo , Produtos Biológicos/análise , Produtos Biológicos/metabolismo , Biologia Computacional/métodos , Genoma/genética , Aprendizado de Máquina , Família Multigênica/genética , Peptídeos/genética , Processamento de Proteína Pós-Traducional/fisiologia , Ribossomos/metabolismo
16.
J Hered ; 114(6): 654-668, 2023 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-37646645

RESUMO

The schizothoracine fishes, widely distributed in the Qinghai-Tibetan Plateau and its adjacent areas, are considered as ideal models for investigation of high-altitude adaptation. Schizophygopsis are one group of the highly specialized schizothoracine fishes, and the genetic basis for their high-altitude adaptation is poorly understood. In this study, we performed comparative genomics analyses to investigate the potential genetic mechanisms for high-altitude adaptation of Schizopygopsis malacanthus and Schizopygopsis pylzovi based on the chromosome-level genomes. Functional enrichment analysis revealed that many expanded gene families in Schizopygopsis were associated with immune response while many contracted gene families were functionally associated with olfaction. Among the 123 positively selected genes (PSGs), angpt2a was detected in HIF-1 signaling pathway and possibly related to the hypoxia adaptation of Schizopygopsis. Furthermore, two PSGs cox15 and ndufb10 were distributed in thermogenesis, and there was a Schizopygopsis-specific missense mutation in cox15 (Gln115Glu), which possibly contributed to the cold temperature adaptation of the Schizopygopsis. Kyoto Encyclopedia of Genes and Genomes enrichment of the PSGs revealed three significant pathways including metabolic pathways, cell cycle, and homologous recombination and Gene Ontology enrichment analysis of the PSGs revealed several categories associated with DNA repair, cellular response to DNA damage stimulus, and metabolic process. Chromosome-scale characterization of olfactory receptor (OR) repertoires indicated that Schizopygopsis had the least number of OR genes, and the OR gene contraction was possibly caused by the limited food variety and the environmental factors such as lower air pressure, lower humidity, and lower temperature. Our study will help expand our understanding of the potential adaptive mechanism of Schizopygopsis to cope with the high-altitude conditions.


Assuntos
Altitude , Cyprinidae , Animais , Filogenia , Cyprinidae/genética , Genoma , Cromossomos , Adaptação Fisiológica/genética , Tibet
17.
Biotechnol Lett ; 45(7): 847-859, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37171698

RESUMO

OBJECTIVES: PEL3, an alkaline pectinase, exhibited the highest activity among documented alkaline pectate lyases reported in our early study. Unfortunately, undesired thermal stability hampering its industrial application. The purpose of this study is to enhance the performance of wild-type PEL3 (W-PEL3) based on SpyTag/SpyCatcher-mediated cyclization. RESULTS: The cyclized PEL3 (C-PEL3) was observed to fold correctly and generate a spatial conformation in a head-to-tail manner in E. coli. C-PEL3 exhibited comparable optimum pH and temperature to those of W-PEL3. Moreover, the catalytic activity of C-PEL3 increased by 23% compared to W-PEL3, and the kcat/Km of C-PEL3 was 1.5-fold greater than that of the W-PEL3. Importantly, C-PEL3 showed improved stability compared to W-PEL3. Firstly, C-PEL3 displayed a 65% increase in residual activity after treatment at 55 °C for 30 min. Secondly, C-PEL3 was prone to resist heat-induced protein aggregation. Thirdly, C-PEL3 exhibited metal ion stability. Circular dichroism analysis revealed that C-PEL3 was more capable of maintaining its secondary structures than W-PEL3 upon heat treatment. CONCLUSIONS: C-PEL3, the initial example of a circular pectinase through SpyTag/SpyCatcher cyclization, exhibits superior performance and represents a highly encouraging contender for industrial utilization.


Assuntos
Escherichia coli , Poligalacturonase , Ciclização , Escherichia coli/genética , Proteínas/química , Temperatura
18.
Adv Exp Med Biol ; 1419: 63-71, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37418206

RESUMO

The increased aging population who have aging-related diseases poses a serious challenge to health services, including mental health services. Due to the changes of body, brain, living environment, and lifestyle, the elderly will have different psychological changes from other age stages, some of which would develop into mental disorders, and affect the cognition of the elderly in turn. This elderly mental health condition has drawn wide attention from scientists. This chapter introduces the two most common emotional and affective disorders, late-life depression and anxiety, and focuses on their epidemiology and impact on the elderly. Furthermore, this chapter also reviews the effects of these two disorders on cognitive function and cognitive impairment in the elderly, and tries to explain the underlying mechanism of this effect from the perspective of related disease, cerebral circuit, and molecular biology.


Assuntos
Transtornos Cognitivos , Envelhecimento Cognitivo , Humanos , Idoso , Transtornos Cognitivos/epidemiologia , Transtornos Cognitivos/psicologia , Transtornos do Humor/epidemiologia , Encéfalo , Envelhecimento , Cognição
19.
Artigo em Inglês | MEDLINE | ID: mdl-38064616

RESUMO

Objective: This study was carried out to evaluate the clinical efficacy of proprotein convertase chymotrypsin 9 (PCSK9) inhibitors in multi-branch lesions in coronary artery disease with substandard lipid-lowering effects. Methods: This retrospective study collected the clinical data of 100 patients with multiple coronary artery diseases admitted to our hospital between May 2020 and August 2022 for analysis. The eligible patients were assigned to either a PCSK9 inhibitor group or a control group at a ratio of 1:1 by their dosing regimens, with 50 cases in each group. Outcome measures for the clinical efficacy of PCSK9 inhibitors included lipid levels, low-density lipoprotein cholesterol (LDL-C) changes, serum concentrations of coronary artery disease-related inflammatory factors, improvement of angina questionnaire scores, adverse reactions, and major cardiovascular adverse events. Results: PCSK9 inhibitors resulted in significantly lower serum concentrations of total cholesterol (TC), LDL-C, and ApoB and higher high-density lipoprotein cholesterol (HDL-C) levels versus conventional lipid-lowering medication (P < .05). The two arms exhibited similar serum concentrations of triglyceride (TG) and ApoA1 after treatment (P > .05). With LDL-C<1.4 mmol/L as the cut-off for desirable blood lipid levels, 47 (94%) patients reached the standard after in the PCSK9 inhibitors group, while no eligible cases were reported in the control group (P < .05). PCSK9 inhibitors provided a marked reduction in the serum concentrations of high-sensitivity C-reactive protein in the patients. Patients had higher angina stability (AS), angina flare (AF), physical limitation (PL), and treatment satisfaction (TS) scores after PCSK9 inhibitor administration versus after conventional medication (P < .05). PCSK9 inhibitors were associated with a significantly lower incidence of adverse cardiovascular events (10%) versus conventional medication (42%) (P < .05). Conclusion: PCSK9 inhibitors significantly improve the LDL-C concentrations of patients with multiple lesions of coronary artery disease who have failed to meet lipid-lowering targets, this enables physicians to more effectively manage patients' cholesterol levels, consequently reducing their cardiovascular risk. Moreover, these inhibitors have the potential to enhance patients' quality of life by alleviating relieve angina symptoms. These findings offer valuable insights into managing multi-branch coronary artery disease.

20.
Sensors (Basel) ; 23(9)2023 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-37177639

RESUMO

Variations of seawater salinity often cause ocean internal waves, water masses and stratification, which affect the stability of the ocean environment. Therefore, the study of seawater salinity is significant for the prediction of changes in the ocean environment. However, existing methods for measuring seawater salinity generally have the disadvantages of low sensitivity and low accuracy. In this work, we proposed a seawater salinity sensor based on long period fiber grating (LPFG) in the dispersion turning point (DTP), which has demonstrated the possibility to fabricate LPFG with a shorter grating period by CO2 laser in a thin single mode fiber (SMF) of 80 µm cladding diameter without etching. For obtaining higher sensitivity that could meet the measurement requirement in practice, the proposed sensor was optimized by combining etching cladding and DTP. After the LPFG working near DTP was fabricated by a CO2 laser, the cladding diameter was reduced to 57.14 µm for making cladding mode LP1,7 work near DTP by hydrofluoric acid (HF) solutions. The experimental results have demonstrated that a sensitivity of 0.571 nm/‱ can be achieved when the salinity increases from 5.001‱ to 39.996‱, and the sensor shows good repeatability and stability. Based on its excellent performance, the optimized LPFG is a prospective sensor to monitor seawater salinity in real time. Meanwhile, a low-cost way was provided to make LPFG work near DTP instead of ultraviolet exposure and femtosecond laser writing.

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