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1.
J Hazard Mater ; 479: 135729, 2024 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-39243547

RESUMO

Vibrio alfacsensis is traditionally seen as an environmental symbiont within its genus, with no detailedly documented pathogenicity in marine aquaculture to date. This study delves into the largely unexplored pathogenic potential and emerging antibiotic resistance of V. alfacsensis. The VA-1 strain, isolated from recirculating aquaculture system (RAS) effluent of cultured turbot (Scophthalmus maximus), underwent comprehensive analysis including biochemical identification, antibiotic susceptibility testing and reinfection trials. The results confirmed VA-1's pathogenicity and significant multiple antibiotic resistance. VA-1 could induce systemic infection in turbot, with symptoms like kidney enlargement, exhibiting virulence comparable to known Vibrio pathogens, with an LD50 around 2.36 × 106 CFU/fish. VA-1's remarkable resistance phenotype (14/22) suggested potential for genetic exchange and resistance factor acquisition in aquaculture environments. Phylogenetic analysis based on 16S rDNA sequences and whole-genome sequencing has firmly placed VA-1 within the V. alfacsensis clade, while genome-wide analysis highlights its similarity and diversity in relation to strains from across the globe. VA-1 contained numerous replicons, indicating the possibility for the spread of resistance and virulence genes. This study suggests V. alfacsensis may acquire and transfer pathogenic and resistant traits through horizontal gene transfer, a likelihood intensified by changing environmental and aquaculture conditions, highlighting the need for vigilant pathogen monitoring and new non-antibiotic treatments.


Assuntos
Antibacterianos , Aquicultura , Farmacorresistência Bacteriana Múltipla , Doenças dos Peixes , Linguados , Vibrio , Animais , Linguados/microbiologia , Vibrio/efeitos dos fármacos , Vibrio/genética , Vibrio/patogenicidade , Doenças dos Peixes/microbiologia , Farmacorresistência Bacteriana Múltipla/genética , Antibacterianos/farmacologia , Vibrioses/microbiologia , Vibrioses/veterinária , Filogenia , Virulência , Testes de Sensibilidade Microbiana , RNA Ribossômico 16S/genética
2.
Elife ; 132024 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-39259595

RESUMO

Carnivores play key roles in maintaining ecosystem structure and function as well as ecological processes. Understanding how sympatric species coexist in natural ecosystems is a central research topic in community ecology and biodiversity conservation. In this study, we explored intra- and interspecific niche partitioning along spatial, temporal, and dietary niche partitioning between apex carnivores (wolf Canis lupus, snow leopard Panthera uncia, Eurasian lynx Lynx lynx) and mesocarnivores (Pallas's cat Otocolobus manul, red fox Vulpes vulpes, Tibetan fox Vulpes ferrilata) in Qilian Mountain National Park, China, using camera trapping data and DNA metabarcoding sequencing data. Our study showed that apex carnivore species had more overlap temporally (coefficients of interspecific overlap ranging from 0.661 to 0.900) or trophically (Pianka's index ranging from 0.458 to 0.892), mesocarnivore species had high dietary overlap with each other (Pianka's index ranging from 0.945 to 0.997), and apex carnivore and mesocarnivore species had high temporal overlap (coefficients of interspecific overlap ranging from 0.497 to 0.855). Large dietary overlap was observed between wolf and snow leopard (Pianka's index = 0.892) and Pallas's cat and Tibetan fox (Pianka's index = 0.997), suggesting the potential for increased resource competition for these species pairs. We concluded that spatial niche partitioning is likely to key driver in facilitating the coexistence of apex carnivore species, while spatial and temporal niche partitioning likely facilitate the coexistence of mesocarnivore species, and spatial and dietary niche partitioning facilitate the coexistence between apex and mesocarnivore species. Our findings consider partitioning across temporal, spatial, and dietary dimensions while examining diverse coexistence patterns of carnivore species in Qilian Mountain National Park, China. These findings will contribute substantially to current understanding of carnivore guilds and effective conservation management in fragile alpine ecosystems.


Assuntos
Ecossistema , Raposas , Animais , China , Raposas/fisiologia , Parques Recreativos , Gatos , Lobos/fisiologia , Carnívoros/fisiologia , Dieta , Lynx/fisiologia , Análise Espaço-Temporal , Panthera/fisiologia , Biodiversidade
3.
Biofouling ; 40(9): 538-548, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39212053

RESUMO

To improve the durability of the photobioreactor antibiofouling surface for microalgal cultivation, a series of photoreactive poly(2,2,2-trifluoroethyl methacrylate) (PTFEMA) were successfully synthesized and used to modify ethylene-vinyl acetate (EVA) films by a surface coating and UV light grafting method. Fourier transform infrared (FT-IR) spectra, X-ray photoelectron spectroscopy analysis (XPS) and fluorescence microscopy results indicated that PTFEMA were fixed successfully onto the EVA film surface through a covalent bond. During the microalgal adhesion assay, the number of EVA-PTFEMA film-adhered microalgae was 41.4% lower than that of the EVA film. Moreover, the number of microalgae attached to the EVA-PTFEMA film decreased by 61.7% after cleaning, while that of EVA film decreased by only 49.1%. It was found that the contact angle of EVA-PTFEMA film surface increased, and remained stable when immersed in acid and alkali solution for up to 90 days.HIGHLIGHTSDurable photobioreactor antibiofouling surfaces for microalgal cultivation were prepared successfully.The contact angle of antibiofouling coating surface remained stable in acid and base environment for 90 days.The attached microalgae on antibiofouling surface decreased 41.4% than those of unmodified surface.The attached microalgae on antibiofouling surface could be cleaned by 61.7% through changing the flow velocity of microalgal suspension.


Assuntos
Incrustação Biológica , Microalgas , Fotobiorreatores , Propriedades de Superfície , Microalgas/crescimento & desenvolvimento , Incrustação Biológica/prevenção & controle , Metacrilatos/farmacologia , Espectroscopia Fotoeletrônica , Raios Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier
4.
Jt Dis Relat Surg ; 35(3): 521-528, 2024 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-39189560

RESUMO

OBJECTIVES: The aim of this study was to investigate the efficacy of three-dimensional (3D) printing-assisted treatment for acetabular fractures (AFs) and to compare with conventional surgical methods. PATIENTS AND METHODS: Between May 2019 and May 2022, a total of 44 patients (33 males, 11 females; mean age: 40.6±11.8 years; range, 20 to 68 years) who were diagnosed with AFs based on clinical symptoms, X-ray and computed tomography (CT) and underwent open reduction and internal fixation in Hospital of Xinjiang Production and Construction Corps were retrospectively analyzed. The patients were divided into two groups based on whether 3D printing was applied as the experimental group (n=24) and control group (n=20). In the experimental group, pelvic and acetabular data were imported into a 3D printer, and an equal-scale highly simulated model was printed using photosensitive resin as the 3D printing material. The model was used to develop more specific personalized surgical plans, to determine the optimal sequence of surgical procedures for fracture reduction, and simulate surgery in vitro. RESULTS: In the experimental group, the mean surgical duration was shorter (123.57±22.05 vs. 163.57±26.20 min, p<0.001), the mean intraoperative bleeding loss was lower (557.14±174.15 vs. 885.71±203.27 mL, p<0.001), and the frequency of intraoperative fluoroscopy was lower (8.64±1.65 vs. 12.07±2.76, p<0.001) than in the control group. No statistically significant differences were found between the two groups in the Visual Analog Scale scores after surgery or the hip function score after treatment (p>0.05). No major postoperative complications were observed in any of the patients. CONCLUSION: Compared to conventional surgical treatment, preoperative 3D printing-assisted treatment for adult patients with AFs can significantly reduce surgical duration, intraoperative bleeding loss and frequency of intraoperative C-arm fluoroscopy, reducing surgical difficulty and improving surgical safety.


Assuntos
Acetábulo , Fixação Interna de Fraturas , Fraturas Ósseas , Impressão Tridimensional , Humanos , Masculino , Acetábulo/lesões , Acetábulo/cirurgia , Acetábulo/diagnóstico por imagem , Feminino , Pessoa de Meia-Idade , Adulto , Estudos Retrospectivos , Fraturas Ósseas/cirurgia , Fraturas Ósseas/diagnóstico por imagem , Idoso , Fixação Interna de Fraturas/métodos , Adulto Jovem , Resultado do Tratamento , Cirurgia Assistida por Computador/métodos , Tomografia Computadorizada por Raios X , Duração da Cirurgia , Redução Aberta/métodos
5.
Phys Chem Chem Phys ; 26(35): 22982-22989, 2024 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-39171568

RESUMO

The excitonic effect significantly influences the optoelectronic characteristics of halide perovskites. However, consensus on the temperature modulated exciton binding energy remains elusive, even for extensively studied materials like MAPbBr3 perovskites. In this study, we utilized UV-vis absorption spectra and the Elliott model to extract the exciton binding energies of MAPbBr3 in the range of 170-290 K. Elliott model fitted results reveal a linear increasing trend in bandgap and exciton binding energy for both cubic and tetragonal phases with temperature, with the tetragonal phase exhibiting a higher increasing rate. Additionally, we found that regardless of the temperature, the strongest absorption peaks are always dominated by the exciton absorption, and our fitted exciton absorption peak blue-shifts with the increase of temperature, accounting for the observed blue-shift of the strongest absorption peak for our fabricated MAPbBr3 sample. However, with the increase of temperature, the weight of continuum state absorption increases significantly, which widens the absorption tails to the longer wavelength, leading to the red-shift of Tauc-plotted optical bandgaps. This is the first work considering the temperature-modulated excitonic properties of halide perovskites, which offers valuable insights into the behavior of MAPbBr3 under varying temperature conditions. After a series of theoretical simulations on the temperature modulated electronic properties, including band structures, carrier effective masses, optical dielectric properties and Born effective charges, we provide rational interpretations for the experimentally observed temperature induced variation of the optical properties. These works are helpful to deepen our understanding of the temperature modulated optical properties of MAPbBr3 perovskites.

6.
Acta Trop ; 258: 107355, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39122103

RESUMO

Migratory birds play an important role in the cross-regional transmission of zoonotic pathogens. Assessing the presence of zoonotic pathogens carried by migratory birds is critical for disease control. However, information about Blastocystis infection in the migratory birds is very limited. Thus, we conducted this study with the aim to explore the occurrence, prevalence and subtyping of Blastocystis in four breeds of migratory birds in northeastern China. From October 2022 to April 2023, a total of 427 fresh fecal samples were obtained from four breeds of migratory birds in five nature reserves in northeastern China, and screened for Blastocystis by PCR amplification. Twenty-one (4.92 %) of the studied samples were confirmed Blastocystis-positive, and two known zoonotic subtypes ST6 and ST7 were founded, with ST7 being the major subtype. Until now, we firstly reported the infection status and subtyping of Blastocystis in the migratory Greater White-Fronted Goose, White Stork, Oriental White Stork and Bean Goose in China. More importantly, these findings present further data on the genetic diversity and transmission routes of Blastocystis and further arouse public health concerns about this organism.


Assuntos
Migração Animal , Doenças das Aves , Aves , Infecções por Blastocystis , Blastocystis , Fezes , Animais , Blastocystis/genética , Blastocystis/classificação , Blastocystis/isolamento & purificação , China/epidemiologia , Infecções por Blastocystis/veterinária , Infecções por Blastocystis/epidemiologia , Infecções por Blastocystis/parasitologia , Doenças das Aves/parasitologia , Doenças das Aves/epidemiologia , Aves/parasitologia , Fezes/parasitologia , Prevalência , Filogenia , Variação Genética , Reação em Cadeia da Polimerase , DNA de Protozoário/genética
7.
Adv Healthc Mater ; : e2402453, 2024 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-39118587

RESUMO

Gram-positive S. aureus is one of the leading pathogens for death associated with antimicrobial resistance. The ß-lactamase (Bla) secreted by methicillin-resistant S. aureus (MRSA) hydrolyzes nearly all ß-lactam antibiotics, leaving only a few antibiotics available for the clinical treatment of MRSA infections. Thereby, a Bla-responsive peptide (BLAP) is designed here with the capacity of inhibiting MRSA infection through mimicking the host defense mechanism of human defensin-6. The BLAP comprising a self-assembling peptide sequence can respond specifically to the secreted Bla and assemble in situ surrounding MRSA. The assembled nanofibrous network is able to trap MRSA, preventing its invasion into the host cells effectively. As a consequence, the intramuscular injection of BLAP significantly restricted bacterial infection and abscess formation in mice. The biomimetic BLAP holds great potential for the efficient treatment of drug-resistant gram-positive bacterial infections.

8.
ACS Med Chem Lett ; 15(8): 1242-1249, 2024 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-39140067

RESUMO

Osteoporosis, a global bone disease, results in decreased bone density, mass, and microarchitecture deterioration, increasing fracture risk. In previous research, FRATtide, a peptide derived from a glycogen synthase kinase-3 binding protein, effectively hindered osteoclast differentiation to yield therapeutically potent derivatives via single and double stapling. However, FRATtide's structure-activity relationship remains unclear. This study synthesized 25 FRATtide-derived peptides through systematic alanine scanning and evaluated their activities. Substitutions in Pro2, Leu5, Leu9, Val10, Leu11, Ser12, Asn14, Leu15, Ile16, Glu18, Arg22, Ser25, and Arg26 showed reduced activity, while FRT13 and FRT20 with Gly13 and Arg21 substitutions, respectively, displayed enhanced activities. F-actin binding and bone resorption assays on FRT13 and FRT20 showed better inhibition of osteoclast differentiation and bone resorption compared with FRATtide. This study elucidated FRATtide's structure-activity relationship, thereby facilitating future structural optimization for osteoporosis treatment.

9.
Chin J Integr Med ; 30(10): 938-948, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-38958884

RESUMO

Hypertensive renal damage (HRD) is a major cause of end-stage renal disease. Among the causes of end-stage renal disease, HRD accounts for nearly 34% of the total number of cases. Antihypertensive treatment is primarily drug-based, but therapeutic efficacy is less effective and can have serious side effects. Chinese medicine (CM) has significant advantages in the treatment of HRD. CM is rich in various active ingredients and has the property of targeting multiple targets and channels. Therefore, the regulatory network of CM on disease is complex. A large number of CM have been employed to treat HRD, either as single applications or as part of compound formulations. The key possible mechanisms of CM for HRD include regulation of the renin-angiotensin-aldosterone system, antioxidation, anti-inflammation, rescue of endothelial function, regulation of vasoactive substance secretion and obesity-related factors, etc. This review summarized and discussed the recent advance in the basic research mechanisms of CM interventions for HRD and pointed out the challenges and future prospects.


Assuntos
Medicina Tradicional Chinesa , Humanos , Medicamentos de Ervas Chinesas/uso terapêutico , Medicamentos de Ervas Chinesas/farmacologia , Sistema Renina-Angiotensina/efeitos dos fármacos , Hipertensão Renal/tratamento farmacológico , Hipertensão/tratamento farmacológico , Animais , Nefrite
10.
Adv Healthc Mater ; : e2400149, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-39007278

RESUMO

Alzheimer's disease (AD) poses a significant burden on the economy and healthcare systems worldwide. Although the pathophysiology of AD remains debatable, its progression is strongly correlated with the accumulation of tau aggregates. Therefore, tau clearance from brain lesions can be a promising strategy for AD therapy. To achieve this, the present study combined proteolysis-targeting chimera (PROTAC), a novel protein-degradation technique that mediates degradation of target proteins via the ubiquitin-proteasome system, and a neurotransmitter-derived lipidoid (NT-lipidoid) nanoparticle delivery system with high blood-brain barrier-penetration activity, to generate a novel nanomedicine named NPD. Peptide 1, a cationic tau-targeting PROTAC is loaded onto the positively charged nanoparticles using DNA-intercalation technology. The resulting nanomedicine displayed good encapsulation efficiency, serum stability, drug release profile, and blood-brain barrier-penetration capability. Furthermore, NPD potently induced tau clearance in both cultured neuronal cells and the brains of AD mice. Moreover, intravenous injection of NPD led to a significant improvement in the cognitive function of the AD mice, without any remarkable abnormalities, thereby supporting its clinical development. Collectively, the novel nanomedicine developed in this study may serve as an innovative strategy for AD therapy, since it effectively and specifically induces tau protein clearance in brain lesions, which in turn enhances cognition.

11.
J Invertebr Pathol ; 204: 108091, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38462166

RESUMO

Ameson portunus is an intracellular pathogen that infects marine crabs Portunus trituberculatus and Scylla paramamosain, causing significant economic losses. However, research into this important parasite has been limited due to the absence of an in vitro culture system. To address this challenge, we developed an in vitro cultivation model of A. portunus using RK13 cell line in this study. The fluorescent labeling assay indicated a high infection rate (∼60 %) on the first day post-infection and quantitative PCR (qPCR) detection demonstrated successful infection as early as six hours post-inoculation. Fluorescence in situ hybridization (FISH) and qPCR were used for the detection of A. portunus infected cells. The FISH probe we designed allowed detection of A. portunus in infected cells and qPCR assay provided accurate quantification of A. portunus in the samples. Transmission electron microscopy (TEM) images revealed that A. portunus could complete its entire life cycle and produce mature spores in RK13 cells. Additionally, we have identified novel life cycle characteristics during the development of A. portunus in RK 13 cells using TEM. These findings contribute to our understanding of new life cycle pathways of A. portunus. The establishment of an in vitro culture model for A. portunus is critical as it provides a valuable tool for understanding the molecular and immunological events that occur during infection. Furthermore, it will facilitate the development of effective treatment strategies for this intracellular pathogen.


Assuntos
Braquiúros , Microsporídios , Animais , Microsporídios/fisiologia , Microsporídios/genética , Braquiúros/parasitologia , Braquiúros/microbiologia , Linhagem Celular , Hibridização in Situ Fluorescente
12.
Curr Protoc ; 4(2): e989, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38363064

RESUMO

Acne vulgaris (acne) effects nearly 90% of all Western teenagers, and the only pharmaceutical class of agents to treat severe forms of this skin condition are the retinoids, which are well-described teratogens. Yet about 50% of the patients receiving this class of therapeutics are women of child-bearing age, in their peak years of reproductive potential. On this basis, there is a significant unmet medical need for agents to treat severe forms of acne that do not carry this liability. As a means to assess potential agents of this type, here we describe methods for estimating the relative amount of sebum that a mouse produces based on the water retention on fur following a thorough wetting procedure. We have shown that a compound that is clinically effective in reducing sebum production demonstrates activity in this model. The method is therefore useful for evaluating therapeutic candidates for reducing sebum production, which would in turn be useful for treating acne. We have broken the entire procedure down into two phases/two protocols, as listed below. © 2024 Wiley Periodicals LLC. Basic Protocol 1: Pre-wash wet weight measurement Basic Protocol 2: Post-wash wet-weight measurement.


Assuntos
Acne Vulgar , Sebo , Adolescente , Humanos , Feminino , Camundongos , Animais , Masculino , Modelos Animais de Doenças , Acne Vulgar/tratamento farmacológico , Retinoides/uso terapêutico , Equilíbrio Hidroeletrolítico
13.
J Med Chem ; 67(2): 1360-1369, 2024 01 25.
Artigo em Inglês | MEDLINE | ID: mdl-38195392

RESUMO

In spite of effective antiosteoporosis potency, teriparatide, a bone-building agent approved by the FDA (Food and Drug Administration), was proven to exhibit various side effects. In our previous work, we developed a universal strategy for synthesizing arginine N-glycosylated peptides termed silver-promoted solid-phase glycosylation (SSG) strategy. However, it is unknown whether the SSG strategy can be applied in the peptide drug design. Herein, we first reported the optimization of teriparatide via SSG strategy. Using Arg20 and/or Arg25 as the modifying positions, three series of arginine N-glycosylated teriparatide analogs were successfully synthesized, of which the introduced sugar groups included glucose, galactose, mannose, rhamnose, ribose, 2-acetamino-2-deoxy-glucose, xylose, lactose, and maltose. Among the 27 arginine N-glycosylated derivatives, Arg20-xylose and Arg25-maltose teriparatide analogs, termed PTH-1g and PTH-2i, respectively, indicated enhanced serum stability and significantly improved antiosteoporotic activities in vitro and in vivo compared with the native counterpart. They may serve as effective therapeutic candidates for treating osteoporosis.


Assuntos
Conservadores da Densidade Óssea , Teriparatida , Teriparatida/farmacologia , Teriparatida/uso terapêutico , Prata/farmacologia , Glicosilação , Maltose/farmacologia , Xilose/farmacologia , Peptídeos/farmacologia , Glucose/farmacologia , Lactose , Catálise , Conservadores da Densidade Óssea/farmacologia , Conservadores da Densidade Óssea/uso terapêutico , Densidade Óssea
14.
J Pept Sci ; 30(6): e3566, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38271799

RESUMO

Figainin 2 is a cationic, hydrophobic, α-helical host-defense peptide with 28 residues, which was isolated from the skin secretions of the Chaco tree frog. It shows potent inhibitory activity against both Gram-negative and Gram-positive pathogens and has garnered considerable interest in developing novel classes of natural antibacterial agents. However, as a linear peptide, conformational flexibility and poor proteolytic stability hindered its development as antibacterial agent. To alleviate its susceptibility to proteolytic degradation and improve its antibacterial activity, a series of hydrocarbon-stable analogs of Figainin 2 were synthesized and evaluated for their secondary structure, protease stability, antimicrobial, and hemolytic activities. Among them, F2-12 showed significant improvement in protease resistance and antimicrobial activity compared to that of the template peptide. This study provides a promising strategy for the development of antimicrobial drugs.


Assuntos
Antibacterianos , Peptídeos Catiônicos Antimicrobianos , Testes de Sensibilidade Microbiana , Antibacterianos/farmacologia , Antibacterianos/química , Antibacterianos/síntese química , Peptídeos Catiônicos Antimicrobianos/farmacologia , Peptídeos Catiônicos Antimicrobianos/química , Peptídeos Catiônicos Antimicrobianos/síntese química , Animais , Proteólise , Hemólise/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Humanos , Relação Estrutura-Atividade , Estrutura Secundária de Proteína , Bactérias Gram-Negativas/efeitos dos fármacos , Estabilidade Proteica
15.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-1006573

RESUMO

Patients with cancer-related fatigue are prone to symptoms and signs such as anorexia, weight loss, and abdominal distension, which seriously reduces the quality of life and becomes an independent risk factor affecting the survival rate of patients with malignant tumors. Therefore, it is urgent to find effective treatment strategies and drugs. In the past, the academic viewpoint of improving syndromes—a new strategy for tumor treatment was proposed based on the guidance of the Luobing theory. Based on this, this article proposes the pathogenesis of cancer-related fatigue is characterized by spleen and kidney deficiency, stasis and toxin internal obstruction, as well as the treatment method of strengthening the spleen and tonifying the kidney, resolving blood stasis and detoxification guided by the core theory of the Qiluo doctrine of Chengzhi Tiaoping. The representative drug Yangzheng Xiaoji capsules has been developed, not only has good therapeutic effect on solid tumors, but also shows good advantages in treating cancer-related fatigue, which can help to restore the homeostasis of tumor bearing survival in patients with malignant tumors and provide new drug choices for the clinical treatment of cancer-related fatigue.

16.
Front Chem ; 11: 1285116, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37965211

RESUMO

[This corrects the article DOI: 10.3389/fchem.2022.840131.].

17.
Bioresour Technol ; 390: 129859, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37832851

RESUMO

Improving high-temperature tolerance of microalgae is crucial to enhance the robustness and economy of microalgae industrial production. Herein, a continuous adaptive laboratory evolution (ALE) system was developed to generate the thermotolerant strain of Chlorella sorokiniana. The resulting thermotolerant strain TR42 exhibited excellent cell growth and biomass production at 42 °C, the temperature that the original strain (OS) could not survive. The high-temperature resistant mechanism of TR42 was investigated by integrating the physiology, transcriptome, proteome and metabolome analyses, which involved enhancing antioxidant capacity, maintaining protein homeostasis, remodeling photosynthetic metabolism, and regulating the synthesis of heat-stress related metabolites. The proof-of-concept high-temperature outdoor cultivation demonstrated that TR42 exhibited 1.15- to 5.72-fold increases in biomass production and 1.62- to 7.04-fold increases in lipid productivity compared to those of OS, respectively, which provided a promising platform for microalgae industrial production. Thus, the multi-system thermotolerant mechanism of TR42 offered potential targets for enhancing high-temperature tolerance of microalgae.


Assuntos
Chlorella , Microalgas , Chlorella/metabolismo , Temperatura , Multiômica , Microalgas/metabolismo , Biomassa
18.
Chem Sci ; 14(41): 11499-11506, 2023 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-37886087

RESUMO

Stapled peptides are regarded as the promising next-generation therapeutics because of their improved secondary structure, membrane permeability and metabolic stability as compared with the prototype linear peptides. Usually, stapled peptides are obtained by a hydrocarbon stapling technique, anchoring from paired olefin-terminated unnatural amino acids and the consequent ring-closing metathesis (RCM). To investigate the adaptability of the rigid cyclobutane structure in RCM and expand the chemical diversity of hydrocarbon peptide stapling, we herein described the rational design and efficient synthesis of cyclobutane-based conformationally constrained amino acids, termed (E)-1-amino-3-(but-3-en-1-yl)cyclobutane-1-carboxylic acid (E7) and (Z)-1-amino-3-(but-3-en-1-yl)cyclobutane-1-carboxylic acid (Z7). All four combinations including E7-E7, E7-Z7, Z7-Z7 and Z7-E7 were proven to be applicable in RCM-mediated peptide stapling to afford the corresponding geometry-specific stapled peptides. With the aid of the combined quantum and molecular mechanics, the E7-E7 combination was proven to be optimal in both the RCM reaction and helical stabilization. With the spike protein of SARS-CoV-2 as the target, a series of cyclobutane-bearing stapled peptides were obtained. Among them, E7-E7 geometry-specific stapled peptides indeed exhibit higher α-helicity and thus stronger biological activity than canonical hydrocarbon stapled peptides. We believe that this methodology possesses great potential to expand the scope of the existing peptide stapling strategy. These cyclobutane-bearing restricted anchoring residues served as effective supplements for the existing olefin-terminated unnatural amino acids and the resultant geometry-specific hydrocarbon peptide stapling provided more potential for peptide therapeutics.

19.
Bioorg Med Chem Lett ; 96: 129499, 2023 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-37804993

RESUMO

A4K14-Citropin 1.1 (GLFAVIKKVASVIKGL-NH2) is a derived antimicrobial peptide (AMP) with a more stable α-helical structure at the C-terminal compared to prototype Citropin 1.1 which was obtained from glandular skin secretions of Australian freetail lizards. In a previous report, A4K14-Citropin 1.1 has been considered as an anti-cancer lead compound. However, linear peptides are difficult to maintain stable secondary structure, resulted in poor pharmacokinetic properties. In this study, we designed and synthesized a series of benzyl-stapled derivatives of A4K14-Citropin 1.1. And their physical and chemical properties, as well as biological activity, were both explored. The result showed that AC-CCSP-2-o and AC-CCSP-3-o exhibited a higher degree of helicity and greater anti-cancer activity compared with the prototype peptide. Besides, there was no significant difference in the hemolytic effect between the stapled peptides and the prototype peptide. AC-CCSP-2-o and AC-CCSP-3-o could serve as promising anti-cancer lead compounds for the novel anti-cancer drug development.


Assuntos
Peptídeos Catiônicos Antimicrobianos , Peptídeos Antimicrobianos , Peptídeos Catiônicos Antimicrobianos/farmacologia , Peptídeos Catiônicos Antimicrobianos/química , Proteínas de Anfíbios/química , Estrutura Secundária de Proteína , Conformação Proteica em alfa-Hélice
20.
J Cell Physiol ; 238(11): 2556-2569, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37698039

RESUMO

Family with sequence similarity 20-member C (FAM20C) is a kinase specific to most of the secreted phosphoproteome. FAM20C has been identified as the causative gene of Raine syndrome, initially characterized by lethal osteosclerosis bone dysplasia. However, since the identification of the cases of nonlethal Raine syndrome characterized by hypophosphatemia rickets, the previous definition of Raine syndrome has become debatable and raised a question about the role of mutations of FAM20C in controversial skeletal manifestation in the two forms of the disease. In this study, we aimed to investigate the influence of FAM20C mutations on skeletogenesis. We developed transgenic mice expressing Fam20c mutations mimicking those associated with human lethal and nonlethal Raine syndrome. The results revealed that transgenic mice expressing the mutant Fam20c found in the lethal (KO;G374R) and nonlethal (KO;D446N) Raine syndrome exhibited osteomalacia without osteosclerotic features. Additionally, both mutants significantly increased the expression of the Fgf23, indicating that Fam20c deficiency in skeletal compartments causes hypophosphatemia rickets. Furthermore, as FAM20C kinase activity catalyzes the phosphorylation of secreted proteomes other than those in the skeletal system, global FAM20C deficiency may trigger alterations in other systems resulting in osteosclerosis secondary to hypophosphatemia rickets. Together, the findings of this study suggest that FAM20C deficiency primarily causes hypophosphatemia rickets or osteomalacia; however, the heterogeneous skeletal manifestation in Raine syndrome was not determined solely by specific mutations of FAM20C. The findings also implicated that rickets or osteomalacia caused by FAM20C deficiency would deteriorate into osteosclerosis by the defects from other systems or environmental impacts.


Assuntos
Hipofosfatemia , Osteomalacia , Osteosclerose , Raquitismo , Camundongos , Animais , Humanos , Osteomalacia/complicações , Osteomalacia/genética , Osteosclerose/genética , Osteosclerose/complicações , Mutação/genética , Raquitismo/complicações , Camundongos Transgênicos , Hipofosfatemia/genética , Hipofosfatemia/complicações , Proteínas da Matriz Extracelular/genética , Proteínas da Matriz Extracelular/metabolismo , Proteínas de Ligação ao Cálcio/genética
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