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1.
J Am Chem Soc ; 146(12): 8508-8519, 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38382542

RESUMO

Tricomponent cobalt(salen)-catalyzed carbofunctionalization of unsaturated substrates by radical-polar crossover has the potential to streamline access to broad classes of heteroatom-functionalized synthetic targets, yet the reaction platform has remained elusive, despite the well-developed analogous hydrofunctionalizations mediated by high-valent alkylcobalt intermediates. We report herein the development of a cobalt(salen) catalytic system that enables carbofunctionalization. The reaction entails a tricomponent decarboxylative 1,4-carboamination of dienes and provides a direct route to aromatic allylic amines by obviating preformed allylation reagents and protection of oxidation-sensitive aromatic amines. The catalytic system merges acridine photocatalysis with cobalt(salen)-catalyzed regioselective 1,4-carbofunctionalization that facilitates the crossover of the radical and polar phases of the tricomponent coupling process, revealing critical roles of the reactants, as well as ligand effects and the nature of the formal high-valent alkylcobalt species on the chemo- and regioselectivity.

2.
J Org Chem ; 89(12): 8734-8744, 2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-38814709

RESUMO

A gold-catalyzed oxidative rearrangement of propargyl alcohols, derived from commercially available cyclohex-2-en-1-ones and alkynes, was successfully developed for the efficient synthesis of seven-membered rings. Thorough investigations were conducted to optimize the reaction conditions and evaluate its compatibility with various functional groups. Additionally, this methodology was applied to the formal total synthesis of guanacastepene A, demonstrating its practical utility in complex natural product synthesis. This versatile and efficient approach opens up new possibilities for the construction of diverse seven-membered ring systems, providing valuable building blocks for further exploration in drug discovery and the synthesis of intricate molecules.

3.
J Org Chem ; 89(5): 3331-3344, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38363745

RESUMO

A gold(I)-catalyzed hydroamination/cycloisomerization cascade reaction was developed to yield indolizino[8,7-b]indole and indolo[2,3-a]-quinolizine derivatives from 2-ethynyltryptamides. The optimal conditions were determined by condition screening, and the functional group tolerances of these reactions were explored based on synthetic substrates. An insight into the explanation on the selectivity of the ring closure was obtained by density functional theory calculations. A plausible mechanism for the cascade reactions was proposed. Derivatization of the indolizino[8,7-b]indole and total synthesis of nauclefidine demonstrated the practicality of this strategy.

4.
Immunol Invest ; : 1-15, 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38814140

RESUMO

AIM: This study aimed to evaluate the miR-223-5p expression in patients with spinal cord injury (SCI) and to determine its role in the pathogenesis of SCI. METHODS: The serum miR-223-5p levels were analyzed using quantitative real-time polymerase chain reaction. The diagnostic accuracy of miR-223-5p was evaluated using the receiving operating characteristic curves. LPS-induced PC12 cells were established as an in vitro inflammatory cell model. Cell apoptosis, inflammation and oxidative stress were examined. The SCI rat model was constructed to evaluate the effects of miR-223-5p on inflammatory response and motor function in rats. RESULTS: MiR-223-5p expression was upregulated in SCI patients. MiR-223-5p expression in the complete SCI group was significantly higher than that in incomplete SCI group. ROC analysis showed that miR-223-5p can distinguish SCI patients from healthy volunteers. In vitro experiments demonstrated that LPS upregulated apoptosis and inflammation in PC12 cells. Treatment with miR-223-5p inhibitor alleviated the changes in LPS-induced PC12 cells . Inhibition of miR-223-5p can alleviate the activation of inflammatory response and the effects of SCI on the motor function in rats. CONCLUSIONS: MiR-223-5p is a potential diagnostic marker for SCI, and it can promote the SCI progression by regulating nerve cell survival, inflammation, and oxidative stress.

5.
Zygote ; 32(2): 170-174, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38619002

RESUMO

Oocytes with excessively large first polar bodies (PB1) often occur in assisted reproductive procedures. Many times these oocytes are discarded without insemination and, as a result, the application of this portion of oocytes has scarcely been reported to date. Few studies have examined large PB1 oocytes in infertile women and have virtually entirely studied genetic variations for large PB1 oocyte abnormalities. Here, we describe an unusual case of a live birth from a remarkably large PB1 oocyte in a frozen embryo transfer (FET) cycle. This is the first instance of a successful live birth resulting from a PB1 oocyte with an extremely large polar body measuring 80 µM × 40 µM in size. The large PB1 oocyte was performed by an early rescue intracytoplasmic sperm injection (r-ICSI) and was formed into a blastocyst on day 5. Following FET, a healthy boy baby weighing 3100 g was finally delivered by caesarean section at 37 weeks and 5 days after conception. Additionally, there were no complications throughout the antenatal period or the perinatal phase of this following full-term delivery. In this study, it is revealed for the first time that a huge PB1 oocyte can be fertilized, resulting in the growth of a blastocyst, a subsequent pregnancy, and a live birth. This new information prompts us to reconsider the use of large PB1 oocytes. More insightful talks should be given attention to prevent the waste of embryos because not all oocytes with aberrant morphology are unavailable.


Assuntos
Transferência Embrionária , Nascido Vivo , Oócitos , Corpos Polares , Injeções de Esperma Intracitoplásmicas , Humanos , Feminino , Gravidez , Injeções de Esperma Intracitoplásmicas/métodos , Adulto , Oócitos/fisiologia , Oócitos/citologia , Masculino , Transferência Embrionária/métodos , Recém-Nascido , Blastocisto/citologia , Blastocisto/fisiologia , Criopreservação
6.
Opt Express ; 31(5): 8820-8843, 2023 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-36859989

RESUMO

In allusion to the privacy and security problems in 3D point cloud classification, a novel privacy protection method for 3D point cloud classification based on optical chaotic encryption scheme is proposed and implemented in this paper for the first time. The mutually coupled spin-polarized vertical-cavity surface-emitting lasers (MC-SPVCSELs) subject to double optical feedback (DOF) are studied to generate optical chaos for permutation and diffusion encryption process of 3D point cloud. The nonlinear dynamics and complexity results demonstrate that the MC-SPVCSELs with DOF have high chaotic complexity and can provide tremendously large key space. All the test-sets of ModelNet40 dataset containing 40 object categories are encrypted and decrypted by the proposed scheme, and then the classification results of 40 object categories for original, encrypted, and decrypted 3D point cloud are entirely enumerated through the PointNet++. Intriguingly, the class accuracies of the encrypted point cloud are nearly all equal to 0.0000% except for the plant class with 100.0000%, indicating the encrypted point cloud cannot be classified and identified. The decryption class accuracies are very close to the original class accuracies. Therefore, the classification results verify that the proposed privacy protection scheme is practically feasible and remarkably effective. Additionally, the encryption and decryption results show that the encrypted point cloud images are ambiguous and unrecognizable, while the decrypted point cloud images are identical to original images. Moreover, this paper improves the security analysis via analyzing 3D point cloud geometric features. Eventually, various security analysis results validate that the proposed privacy protection scheme has high security level and good privacy protection effect for 3D point cloud classification.

7.
J Org Chem ; 88(16): 11377-11391, 2023 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-37540141

RESUMO

Over the past two decades, synthetic strategies for synthesizing the skeletons of various indole alkaloids based on tryptamine-ynamide have been continuously developed and applied to the total syntheses or formal total syntheses of related molecules. In this synopsis, we summarized the cyclization pathways of tryptamine-ynamide under different catalytic conditions, emphasizing the reaction mechanism and applications in the syntheses of indole alkaloids.

8.
J Org Chem ; 88(11): 7179-7187, 2023 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-37172220

RESUMO

Six 8-oxoprotoberberines were synthesized collectively in four steps with acceptable yields (14-19%), of which the products 8-oxopalmatine, 8-oxopseudopalmatine, 8-oxoberberine, and 8-oxopseudoberberine come from nature. The synthetic route was featured with the In(OTf)3-catalyzed cyclization and Heck coupling. Moreover, the syntheses of the natural products berberine, canadine, and iambertine were achieved via various reductions from 8-oxoberberine, which provided a concise approach to the syntheses of this kind of alkaloids.

9.
J Org Chem ; 88(15): 10586-10598, 2023 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-37449800

RESUMO

Spiro[indoline-3,3'-pyrrolidine] and spiro[indoline-3,3'-piperidine] derivatives were synthesized in a substitution-controlled manner under the catalysis of cationic gold(I) species in the presence of Hantzsch ester (HEH). The optimal reaction condition was determined by screening, and the functional group tolerances of these two pathways were examined by readily synthetic substrates. The endo and exo selectivities of these cyclizations were elucidated by density functional theory calculations, and a plausible mechanism for these transformations was proposed.

10.
J Org Chem ; 88(9): 5483-5496, 2023 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-37043684

RESUMO

Density functional theory calculations were applied to predict the pathways of gold(I)-catalyzed cycloisomerization of the indole substrates with 1,6-enynes, which were consistent with the ensuing experimental results. The substitution-controlled synthesis led to the formation of 1H-pyrido[4,3-b]indole and spiro[indoline-3,3'-pyridine] derivatives in a tunable way. The reactions had good functional group tolerances, and a possible mechanism was proposed based on the computational and experimental results.

11.
Org Biomol Chem ; 21(12): 2610-2619, 2023 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-36896738

RESUMO

The regioselectivity for gold(I)-catalyzed intramolecular cycloisomerizations of tryptamine-ynamides has long been elusive despite various synthetic examples of similar substrates being available. Computational studies were carried out to provide insight into the mechanisms and the origin of the substrate-dependent regioselectivity of these transformations. Based on the analyses of non-covalent interactions, distortion/interaction, and energy decomposition on the interactions between the terminal substituent of alkynes and the gold(I) catalytic ligand, the electrostatic effect was determined to be the key factor for α-position selectivity while the dispersion effect was determined to be the key factor for ß-position selectivity. Our computational results were consistent with the experimental observations. This study provides useful guidance for understanding other similar gold(I)-catalyzed asymmetric alkyne cyclization reactions.

12.
Int J Mol Sci ; 24(2)2023 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-36674895

RESUMO

Calcium/calmodulin-dependent protein kinase (CaMK), a key downstream target protein in the Ca2+ signaling pathway of eukaryotes, plays an important regulatory role in the growth, development and pathogenicity of plant fungi. Three AaCaMKs (AaCaMK1, AaCaMK2 and AaCaMK3) with conserved PKC_like superfamily domains, ATP binding sites and ACT sites have been cloned from Alternaria alternata, However, their regulatory mechanism in A. alternata remains unclear. In this study, the function of the AaCaMKs in the development, infection structure differentiation and pathogenicity of A. alternata was elucidated through targeted gene disruption. The single disruption of AaCaMKs had no impact on the vegetative growth and spore morphology but significantly influenced hyphae growth, sporulation, biomass accumulation and melanin biosynthesis. Further expression analysis revealed that the AaCaMKs were up-regulated during the infection structure differentiation of A. alternata on hydrophobic and pear wax substrates. In vitro and in vivo analysis further revealed that the deletion of a single AaCaMKs gene significantly reduced the A. alternata conidial germination, appressorium formation and infection hyphae formation. In addition, pharmacological analysis confirmed that the CaMK specific inhibitor, KN93, inhibited conidial germination and appressorium formation in A. alternata. Meanwhile, the AaCaMKs genes deficiency significantly reduced the A. alternata pathogenicity. These results demonstrate that AaCaMKs regulate the development, infection structure differentiation and pathogenicity of A. alternata and provide potential targets for new effective fungicides.


Assuntos
Fungicidas Industriais , Pyrus , Pyrus/microbiologia , Virulência/genética , Alternaria , Fungicidas Industriais/farmacologia , Fungicidas Industriais/metabolismo
13.
J Virol ; 95(13): e0033621, 2021 06 10.
Artigo em Inglês | MEDLINE | ID: mdl-33853967

RESUMO

To replicate efficiently and evade the antiviral immune response of the host, some viruses degrade host mRNA to induce host gene shutoff via encoding shutoff factors. In this study, we found that feline calicivirus (FCV) infection promotes the degradation of endogenous and exogenous mRNAs and induces host gene shutoff, which results in global inhibition of host protein synthesis. Screening assays revealed that proteinase-polymerase (PP) is a most effective factor in reducing mRNA expression. Moreover, PP from differently virulent strains of FCV could induce mRNA degradation. Further, we found that the key sites of the PP protein required for its proteinase activity are also essential for its shutoff activity but also required for viral replication. The mechanism analysis showed that PP mainly targets Pol II-transcribed RNA in a ribosome-, 5' cap-, and 3' poly(A) tail-independent manner. Moreover, purified glutathione S-transferase (GST)-PP fusion protein exhibits RNase activity in vitro in assays using green fluorescent protein (GFP) RNA transcribed in vitro as a substrate in the absence of other viral or cellular proteins. Finally, PP-induced shutoff requires host Xrn1 to complete further RNA degradation. This study provides a newly discovered strategy in which FCV PP protein induces host gene shutoff by promoting the degradation of host mRNAs. IMPORTANCE Virus infection-induced shutoff is the result of targeted or global manipulation of cellular gene expression and leads to efficient viral replication and immune evasion. FCV is a highly contagious pathogen that persistently infects cats. It is unknown how FCV blocks the host immune response and persistently exists in cats. In this study, we found that FCV infection promotes the degradation of host mRNAs and induces host gene shutoff via a common strategy. Further, PP protein for different FCV strains is a key factor that enhances mRNA degradation. An in vitro assay showed that the GST-PP fusion protein possesses RNase activity in the absence of other viral or cellular proteins. This study demonstrates that FCV induces host gene shutoff by promoting the degradation of host mRNAs, thereby introducing a potential mechanism by which FCV infection inhibits the immune response.


Assuntos
Calicivirus Felino/crescimento & desenvolvimento , Evasão da Resposta Imune/imunologia , Peptídeo Hidrolases/metabolismo , Estabilidade de RNA/fisiologia , RNA Mensageiro/metabolismo , Ribonucleases/metabolismo , Animais , Infecções por Caliciviridae/patologia , Calicivirus Felino/genética , Calicivirus Felino/metabolismo , Gatos , Linhagem Celular , Células HEK293 , Humanos , Evasão da Resposta Imune/genética , Peptídeo Hidrolases/genética , Biossíntese de Proteínas/fisiologia , Interferência de RNA , RNA Interferente Pequeno/genética , Ribonucleases/genética , Replicação Viral
14.
Org Biomol Chem ; 20(43): 8528-8532, 2022 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-36278495

RESUMO

Two pairs of unprecedented ß-carboline-phenylpropanoid heterogeneous alkaloids, (±)-pheharmines A-B (1-4), characterized by a morpholino[4,3,2-hi]ß-carboline core with two chiral centers, were isolated from the roots of Peganum harmala. The structures, including their absolute configurations, were identified using spectroscopic analyses and electronic circular dichroism (ECD) calculations. The biosynthetic hypothesis for the formation of pheharmines A-B was proposed. Compounds 1-4 exhibited moderate cytotoxic activities against HL-60 cell lines.


Assuntos
Alcaloides , Peganum , Humanos , Peganum/química , Peganum/metabolismo , Morfolinos/análise , Morfolinos/metabolismo , Sementes , Estrutura Molecular , Alcaloides/farmacologia , Alcaloides/química , Carbolinas/farmacologia , Carbolinas/química
15.
J Appl Microbiol ; 133(4): 2631-2641, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35870147

RESUMO

AIMS: Calmodulin (CaM), acts as a kind of multifunctional Ca2+ sensing protein, which is ubiquitous in fungi, is highly conserved across eukaryotes and is involved in the regulation of a range of physiological processes, including morphogenesis, reproduction and secondary metabolites biosynthesis. Our aim was to understand the characteristics and functions of AaCaM in Alternaria alternata, the causal agent of pear black spot. METHODS AND RESULTS: A 450 bp cDNA sequence of AaCaM gene of A. alternata was cloned by the PCR homology method. Sequence analysis showed that this protein encoded by AaCaM was a stable hydrophilic protein and had a high similarity to Neurospora crassa (CAA50271.1) and other fungi. RT-qPCR analysis determined that AaCaM was differentially upregulated during infection structural differentiation of A. alternata both on hydrophobic and pear wax extract-coated surface, with a 3.37-fold upregulation during the hydrophobic induced appressorium formation period (6 h) and a 1.46-fold upregulation during the infection hyphae formation period (8 h) following pear wax induction. Pharmaceutical analysis showed that the CaM-specific inhibitor, trifluoperazine (TFP), inhibited spore germination and appressorium formation, and affected toxins and melanin biosynthesis in A. alternata. CONCLUSIONS: AaCaM plays an important role in regulating infection structure differentiation and secondary metabolism of A. alternata. SIGNIFICANCE AND IMPACT OF STUDY: Our study provides a theoretical basis for further in-depth investigation of the specific role of AaCaM in the calcium signalling pathway underlying hydrophobic and pear wax-induced infection structure differentiation and pathogenicity of A. alternata.


Assuntos
Pyrus , Alternaria/metabolismo , Cálcio/metabolismo , Calmodulina/genética , Calmodulina/metabolismo , DNA Complementar/metabolismo , Melaninas/metabolismo , Preparações Farmacêuticas , Doenças das Plantas/microbiologia , Pyrus/genética , Pyrus/metabolismo , Pyrus/microbiologia , Trifluoperazina/metabolismo
16.
Phytopathology ; 112(10): 2207-2217, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35612304

RESUMO

Fungal pathogens use plant surface physiochemical signals to trigger specific developmental processes. To assess the role of phospholipase C (PLC) in mediating plant stimuli sensing of Alternaria alternata, the function of three PLC genes was characterized by constructing ΔAaPLC mutants. Here we showed that fruit wax-coated surfaces significantly induced appressorium formation in A. alternata and mutants. Germination of ΔAaPLC mutants did not differ from the wild type. Deletion of AaPLC1 led to the decrease of appressorium formation and infected hyphae, but the degree of reduction varies between the different types of waxes, with the strongest response to pear wax. Appressorium formation and infected hyphae of the ΔAaPLC1 mutant on dewaxed onion epidermis mounted with pear wax (θ4) were reduced by 14.5 and 65.7% after 8 h incubation, while ΔAaPLC2 and ΔAaPLC3 formed the same infection hyphae as wild type. In addition, AaPLC1 mutation caused pleiotropic effects on fungal biological function, including growth deficiency, changes in stress tolerance, weakening of pathogenicity to the host, as well as destruction of mycotoxin synthesis. Both AaPLC2 and AaPLC3 genes were found to have some effects on stress response and mycotoxin production. Taken together, AaPLC genes differentially regulate the growth, stress response, pathogenicity, and secondary metabolism of A. alternata.


Assuntos
Micotoxinas , Pyrus , Alternaria/genética , Frutas , Micotoxinas/metabolismo , Doenças das Plantas/microbiologia , Pyrus/microbiologia , Metabolismo Secundário , Fosfolipases Tipo C/genética , Fosfolipases Tipo C/metabolismo , Virulência , Ceras/metabolismo
17.
Arch Gynecol Obstet ; 306(6): 1901-1911, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-35306582

RESUMO

PURPOSE: Chromosomal mosaicism becomes a common phenomenon in Preimplantaion genetic testing (PGT). This meta-analysis was conducted to study which feature of chromosomal mosaicism was compatible for embryo transfer. METHODS: After searching the database PubMed, Embase, CCTR and related reviews up until May 2021. Two reviewers extracted relevant information and assessed study quality by the Newcastle-Ottawa scale independently. Summary Odd Radios (OR) were calculated using fixed- or random-effects models for clinical outcomes. A network meta-analysis compared the clinical outcomes of different chromosomes. RESULTS: A total of six studies with 1,106 cycles of single mosaic embryo transferred were included. Significant results of implantation rate (IR), miscarriage rate (MR), and ongoing pregnancy/live birth rate (OP/LBR) were observed when comparing embryos with mosaicism level < 50% and ≥ 50% [OR 1.42, 95% CI (1.06, 1.89); OR 0.45, 95% CI (0.27, 0.75); OR 1.74, 95% CI (1.28, 2.37)], and embryos with mosaicism with only affecting segmental chromosome(s) and only involving whole chromosome(s) [OR 1.31, 95% CI (1.01, 1.71); OR 0.57, 95% CI (0.36, 0.93); OR 1.51, 95% CI (1.15, 2.00)]. Embryos with only mosaic gains or losses had significant higher IR and OP/LBR than complex mosaicism [Gains vs complex: OR 1.75, 95% CI (1.20, 2.54); OR 1.73, 95% CI (1.16, 2.58). Losses vs complex: OR 1.90, 95% CI (1.34, 2.71); OR 2.10, 95% CI (1.44, 3.07)]. Mosaic embryos with only one chromosome involved had significant favorable outcomes of IR and OP/LBR than with three or more chromosomes involved [OR 1.76, 95% CI (1.23, 2.52); OR 1.86, 95% CI (1.25,2.78)]. Chr. 7, Chr. 2, Chr. 1, Chr. 18, Chr. 11, Chr. X, Chr. 13, Chr. 14, Chr. 12, and Chr. 9 were considered as prioritized chromosomes of mosaic embryos for transfer. CONCLUSIONS: This analysis support the embryos with mosaicism level ≥ 50%, whole chromosome(s) involved, multiple mosaic abnormalities were associated with worse pregnancy outcomes. Mosaicism level of 50% could be used as a threshold to assess the mosaic embryos.


Assuntos
Diagnóstico Pré-Implantação , Gravidez , Feminino , Humanos , Diagnóstico Pré-Implantação/métodos , Mosaicismo , Aneuploidia , Blastocisto , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Transferência Embrionária , Testes Genéticos/métodos , Fertilização in vitro
18.
J Basic Microbiol ; 62(6): 721-739, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35289436

RESUMO

Shiraia bambusicola is a fungus with high economic value widely used in medicine, agriculture, and food. We wished to understand the genes and metabolites changes involved in the different developmental stages of S. bambusicola. So, to reveal key genes and metabolites in the main active metabolite, the  were analyzed in different developmental stages of S. bambusicola fruiting body. A total of 29,137 Unigenes were annotated. In the whole growth process, differentially expressed genes were involved in the pathways of cytochrome P450, transcription factors, transporters, and so on, while in the early stage of growth, genes enriching to synthesis pathways of basic substances. In the middle stage of growth, genes with more prominent changes were involved in the pathways of the cell cycle, cancer mechanisms, and aminobenzoate degradation; in the later stage of growth, differentially expressed genes that enriched synthesis pathways of secondary metabolites. A total of 612 metabolites were detected from different growth stages of S. bambusicola. Among them, coumarins, alkaloids, rutin, liquiritigenin, quercetin, and other medically relevant metabolites were detected for the first time. We have identified 31 secondary metabolites,  relevantly only accumulated in the early and middle stage, but not detected in the later stage, such as flavonols, coumarins, nucleotides and its derivates and hydroxycinnamoyl derivatives. The differential genes and metabolites of the same group were enriched in 127 pathways, and more significantly in ubiquinone and other terpenoid quinone biosynthesis, phenylalanine metabolism, phenylalanine, tyrosine and tryptophan biosynthesis, and phenylpropanoid biosynthesis. The correlation networks of several significantly enriched pathways were analyzed, and the relationships within and between these pathways, genes, and metabolites, were analyzed. The synthetic pathway of hypocrellin has been speculated upon. We believe that hypocrellin is synthesized in S. bambusicola via the shikimic acid pathway followed by phenylalanine, tyrosine, and tryptophan biosynthesis pathway, then the ubiquinone and other terpenoid quinone biosynthesis pathway, and finally a series of polymerization and modification reactions. Several genes and metabolites involved in the biosynthesis of hypocrellin have been identified. This study provides a reference for further research on S. bambusicola, by providing a basis for its use and development.


Assuntos
Transcriptoma , Ubiquinona , Ascomicetos , Cumarínicos , Metabolômica , Fenilalanina , Quinonas/metabolismo , Terpenos , Triptofano , Tirosina
19.
J Basic Microbiol ; 62(12): 1487-1503, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36192145

RESUMO

Aspergillus cristatus is the dominant fungus during the fermentation of Fuzhuan brick tea, hypotonic conditions only induced its sexual development to produce ascospores, while hypertonic conditions only induced its asexual development to produce conidia, indicating that osmotic stress can regulate spore production in A. cristatus. However, the underlying regulatory mechanism is unclear. In this study, the roles of Acpbs2, which is homologous to pbs2 from Saccharomyces cerevisiae, in sporulation, stress responses, the color of colonies, and carbon metabolism were explored in A. cristatus. Deletion mutants of Acpbs2 were obtained by homologous recombination. The time required to produce conidia was delayed, and the number of conidia produced was significantly reduced in hypertonic media in ΔAcpbs2 by phenotypic observations, indicating that Acpbs2 plays a positive role in asexual development. Stress sensitivity tests showed that the order of the sensitivity of ΔAcpbs2 to different osmotic regulators was 3 M NaCl > 3 M sucrose > 3 M sorbitol. Moreover, the deletion mutants were sensitive to high oxidative stress. The growth of the Acpbs2 deletion mutant was inhibited under alkaline-pH stress, indicating that Acpbs2 is involved in high pH stress tolerance. Additionally, compared with the wild type, the colony color of the Acpbs2 deletion mutant became lighter. All the above developmental defects were reversed by the reintroduction of the Acpbs2 gene in ΔAcpbs2. Transcriptome data showed that Acpbs2 regulated the expression of several genes related to conidial development, osmotic stress, oxidative stress, and carbon metabolism. More importantly, the interaction between Acpbs2 and its downstream gene Achog1 was verified by yeast two-hybrid assays. We speculated that this interaction might regulate the osmotic stress response, the oxidative stress response, and asexual sporulation in A. cristatus, which will be one of the focuses of our future research.


Assuntos
Proteínas Fúngicas , Regulação Fúngica da Expressão Gênica , Proteínas Fúngicas/metabolismo , Carbono/metabolismo , Aspergillus/metabolismo , Esporos Fúngicos
20.
Molecules ; 27(24)2022 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-36558089

RESUMO

Gold catalysts possess the advantages of water and oxygen resistance, with the possibility of catalyzing many novel chemical transformations, especially in the syntheses of small-molecule skeletons, in addition to achieving the rapid construction of multiple chemical bonds and ring systems in one step. In this feature paper, we summarize recent advances in the construction of small-molecule scaffolds, such as benzene, cyclopentene, furan, and pyran, based on gold-catalyzed cyclization of arylalkyne derivatives within the last decade. We hope that this review will serve as a useful reference for chemists to apply gold-catalyzed strategies to the syntheses of related natural products and active molecules, hopefully providing useful guidance for the exploration of additional novel gold-catalyzed approaches.


Assuntos
Produtos Biológicos , Ouro , Ouro/química , Produtos Biológicos/química , Ciclização , Catálise
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