RÉSUMÉ
tRNA is the RNA type that undergoes the most modifications among known RNA, and in recent years, tRNA methylation has emerged as a crucial process in regulating gene translation. Dysregulation of tRNA abundance occurs in cancer cells, along with increased expression and activity of tRNA methyltransferases to raise the level of tRNA modification and stability. This leads to hijacking of translation and synthesis of multiple proteins associated with tumor proliferation, metastasis, invasion, autophagy, chemotherapy resistance, and metabolic reprogramming. In this review, we provide an overview of current research on tRNA methylation in cancer to clarify its involvement in human malignancies and establish a theoretical framework for future therapeutic interventions targeting tRNA methylation processes.
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The prevalence of non-small cell lung cancer (NSCLC) accounts for 85% of all lung cancers, with the Wnt/ß-catenin signaling pathway exhibiting robust activation in this particular subtype. The expression of FAM83A (family with sequence similarity 83, member A) has been found to be significantly upregulated in lung cancer, leading to the stabilization of ß-catenin and activation of the Wnt signaling pathway. In this study, we conducted a screening of down-regulated miRNAs in lung cancer with FAM83A as the target. Ultimately, we identified miR-1 as a negative regulator of FAM83A and confirmed that FAM83A is a direct target gene of miR-1 through dual luciferase reporter assays. The overexpression of miR-1 significantly attenuated the expression level of FAM83A and suppressed the Wnt signaling pathway, leading to a reduction in the expression levels of downstream target genes AXIN2, CyclinD1, and C-MYC. Additionally, it decreased the nuclear translocation of ß-catenin. In addition, overexpression of miR-1 accelerated the degradation of ß-catenin by inhibiting FAM83A, promoted the assembly of ß-catenin degradation complex, and inhibited the proliferation, migration and invasion of NSCLC cells. In summary, miR-1 may be a potential candidate miRNA for the treatment of NSCLC.
Sujet(s)
Carcinome pulmonaire non à petites cellules , Régulation de l'expression des gènes tumoraux , Tumeurs du poumon , microARN , Protéines tumorales , Voie de signalisation Wnt , bêta-Caténine , Humains , Carcinome pulmonaire non à petites cellules/génétique , Carcinome pulmonaire non à petites cellules/anatomopathologie , Carcinome pulmonaire non à petites cellules/métabolisme , Voie de signalisation Wnt/génétique , microARN/génétique , microARN/métabolisme , Tumeurs du poumon/génétique , Tumeurs du poumon/anatomopathologie , Tumeurs du poumon/métabolisme , bêta-Caténine/métabolisme , bêta-Caténine/génétique , Lignée cellulaire tumorale , Protéines tumorales/génétique , Protéines tumorales/métabolisme , Prolifération cellulaire/génétique , Mouvement cellulaire/génétique , Cellules A549RÉSUMÉ
Pancreatic cancer is a malignancy with high mortality. In addition to the few symptoms until the disease reaches an advanced stage, the high fatality rate is attributed to its rapid development, drug resistance and lack of appropriate treatment. In the selection and research of therapeutic drugs, gemcitabine is the first-line drug for pancreatic cancer. Solving the problem of gemcitabine resistance in pancreatic cancer will contribute to the progress of pancreatic cancer treatment. Long non coding RNAs (lncRNAs), which are RNA transcripts longer than 200 nucleotides, play vital roles in cellular physiological metabolic activities. Currently, our group and others have found that some lncRNAs are aberrantly expressed in pancreatic cancer cells, which can regulate the process of cancer through autophagy and Wnt/ß-catenin pathways simultaneously and affect the sensitivity of cancer cells to therapeutic drugs. This review presents an overview of the recent evidence concerning the node of lncRNA for the cross-talk between autophagy and Wnt/ß-catenin signaling in pancreatic cancer, together with the practicability of lncRNAs and the core regulatory factors as targets in therapeutic resistance.
Sujet(s)
Autophagie , Résistance aux médicaments antinéoplasiques , Tumeurs du pancréas , ARN long non codant , Voie de signalisation Wnt , ARN long non codant/métabolisme , ARN long non codant/génétique , Humains , Autophagie/effets des médicaments et des substances chimiques , Tumeurs du pancréas/métabolisme , Tumeurs du pancréas/traitement médicamenteux , Tumeurs du pancréas/génétique , Résistance aux médicaments antinéoplasiques/génétique , AnimauxRÉSUMÉ
BACKGROUND: Splicing factors are vital for the regulation of RNA splicing, but some have also been implicated in regulating transcription. The underlying molecular mechanisms of their involvement in transcriptional processes remain poorly understood. RESULTS: Here, we describe a direct role of splicing factor RBM22 in coordinating multiple steps of RNA Polymerase II (RNAPII) transcription in human cells. The RBM22 protein widely occupies the RNAPII-transcribed gene locus in the nucleus. Loss of RBM22 promotes RNAPII pause release, reduces elongation velocity, and provokes transcriptional readthrough genome-wide, coupled with production of transcripts containing sequences from downstream of the gene. RBM22 preferentially binds to the hyperphosphorylated, transcriptionally engaged RNAPII and coordinates its dynamics by regulating the homeostasis of the 7SK-P-TEFb complex and the association between RNAPII and SPT5 at the chromatin level. CONCLUSIONS: Our results uncover the multifaceted role of RBM22 in orchestrating the transcriptional program of RNAPII and provide evidence implicating a splicing factor in both RNAPII elongation kinetics and termination control.
Sujet(s)
Facteur B d'élongation transcriptionnelle positive , RNA polymerase II , Humains , Chromatine , Facteur B d'élongation transcriptionnelle positive/génétique , Facteur B d'élongation transcriptionnelle positive/métabolisme , RNA polymerase II/métabolisme , Épissage des ARN , Facteurs d'épissage des ARN/génétique , Transcription génétique , Facteurs d'élongation transcriptionnelle/génétique , Facteurs d'élongation transcriptionnelle/métabolismeRÉSUMÉ
Transient receptor potential vanilloid-6 (TRPV6) is a cation channel belonging to the TRP superfamily, specifically the vanilloid subfamily, and is the sixth member of this subfamily. Its presence in the body is primarily limited to the skin, ovaries, kidney, testes, and digestive tract epithelium. The body maintains calcium homeostasis using the TRPV6 channel, which has a greater calcium selectivity than the other TRP channels. Several pieces of evidence suggest that it is upregulated in the advanced stages of thyroid, ovarian, breast, colon, and prostate cancers. The function of TRPV6 in regulating calcium signaling in cancer will be covered in this review, along with its potential applications as a cancer treatment target.
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An increasing number of studies have shown that FAM83A, a member of the family with sequence similarity 83 (FAM83), which consists of eight members, is a key tumor therapeutic target involved in multiple signaling pathways. It has been reported that FAM83A plays essential roles in the regulation of Wnt/ß-catenin, EGFR, MAPK, EMT, and other signaling pathways and physiological processes in models of pancreatic cancer, lung cancer, breast cancer, and other malignant tumors. Moreover, the expression of FAM83A could be significantly affected by multiple noncoding RNAs that are dysregulated in malignant tumors, the dysregulation of which is essential for the malignant process. Among these noncoding RNAs, the most noteworthy is the antisense long noncoding (Lnc) RNA of FAM83A itself (FAM83A-AS1), indicating an outstanding synergistic carcinogenic effect between FAM83A and FAM83A-AS1. In the present study, the specific mechanisms by which FAM83A and FAM83A-AS1 cofunction in the Wnt/ß-catenin and EGFR signaling pathways were reviewed in detail, which will guide subsequent research. We also described the applications of FAM83A and FAM83A-AS1 in tumor therapy and provided a certain theoretical basis for subsequent drug target development and combination therapy strategies.
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Tumeurs du poumon , ARN long non codant , Humains , bêta-Caténine/génétique , bêta-Caténine/métabolisme , Phosphatidylinositol 3-kinases/métabolisme , Mouvement cellulaire/génétique , Tumeurs du poumon/anatomopathologie , Récepteurs ErbB/génétique , Récepteurs ErbB/métabolisme , ARN long non codant/génétique , Voie de signalisation Wnt/génétique , Prolifération cellulaire/génétique , Régulation de l'expression des gènes tumoraux , Lignée cellulaire tumorale , Protéines tumorales/métabolismeRÉSUMÉ
Ferroptosis is a non-apoptotic mode of cell death driven by membrane lipid peroxidation and is characterized by elevated intracellular levels of Fe2+, ROS, and lipid peroxidation. Studies have shown that ferroptosis is related to the development of multiple diseases, such as cancer, neurodegenerative diseases, and acute myeloid leukemia. Ferroptosis plays a dual role in the occurrence and development of these diseases. Ferroptosis mainly involves iron metabolism, ROS, and lipid metabolism. Various mechanisms, including epigenetic regulation, have been reported to be deeply involved in ferroptosis. Abnormal epigenetic modifications have been reported to promote tumor onset or other diseases and resistance to chemotherapy drugs. In recent years, diversified studies have shown that epigenetic modification is involved in ferroptosis. In this review, we reviewed the current resistance system of ferroptosis and the research progress of epigenetic modification, such as DNA methylation, RNA methylation, non-coding RNAs, and histone modification in cancer and other diseases by regulating ferroptosis.
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Crop straws provide enormous biomass residues applicable for biofuel production and trace metal phytoremediation. However, as lignocellulose recalcitrance determines a costly process with potential secondary waste liberation, genetic modification of plant cell walls is deemed as a promising solution. Although pectin methylation plays an important role for plant cell wall construction and integrity, little is known about its regulation roles on lignocellulose hydrolysis and trace metal elimination. In this study, we initially performed a typical CRISPR/Cas9 gene-editing for site mutations of OsPME31, OsPME34 and OsPME79 in rice, and then determined significantly upgraded pectin methylation degrees in the young seedlings of three distinct site-mutants compared to their wild type. We then examined distinctively improved lignocellulose recalcitrance in three mutants including reduced cellulose levels, crystallinity and polymerization or raised hemicellulose deposition and cellulose accessibility, which led to specifically enlarged biomass porosity either for consistently enhanced biomass enzymatic saccharification under mild alkali pretreatments or for cadmium (Cd) accumulation up to 2.4-fold. Therefore, this study proposed a novel model to elucidate how pectin methylation could play a unique enhancement role for both lignocellulose enzymatic hydrolysis and Cd phytoremediation, providing insights into precise pectin modification for effective biomass utilization and efficient trace metal exclusion.
Sujet(s)
Oryza , Oryza/métabolisme , Pectine/métabolisme , Cadmium/métabolisme , Biomasse , Dépollution biologique de l'environnement , Lignine/métabolisme , Cellulose/métabolisme , MéthylationRÉSUMÉ
The incidence of Hepatocellular carcinoma (HCC) and HCC-related deaths have remarkably increased over the recent decades. It has been reported that ß-catenin activation can be frequently observed in HCC cases. This study identified the integrin-linked kinase-associated phosphatase (ILKAP) as a novel ß-catenin-interacting protein. ILKAP is localized both in the nucleus and cytoplasm and regulates the WNT pathway in different ways. First, it is demonstrated that ILKAP activates the WNT pathway in HCC cells by increasing the protein level of ß-catenin and other proteins associated with the WNT signaling, such as c-Myc and CyclinD1. Next, it is shown that ILKAP promotes the metastasis of HCC both in vitro and in vivo in a zebrafish xenograft model. It is also found that ILKAP dephosphorylates the GSK3ß and CK1, contributing to the reduced ubiquitination of ß-catenin. Furthermore, it is identified that ILKAP functions by mediating binding between TCF4 and ß-catenin to enhance expression of WNT target genes. Taken together, the study demonstrates a critical function of ILKAP in metastasis of HCC, since ILKAP is crucial for the activation of the WNT pathway via stabilization of ß-catenin and increased binding between TCF4 and ß-catenin.
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Carcinome hépatocellulaire , Tumeurs du foie , Phosphoprotein Phosphatases , Voie de signalisation Wnt , bêta-Caténine , Animaux , Humains , bêta-Caténine/métabolisme , Carcinome hépatocellulaire/anatomopathologie , Carcinome hépatocellulaire/métabolisme , Lignée cellulaire tumorale , Régulation de l'expression des gènes tumoraux , Tumeurs du foie/anatomopathologie , Tumeurs du foie/métabolisme , Métastase tumorale , Facteur-4 de transcription/métabolisme , Facteur-4 de transcription/génétique , Voie de signalisation Wnt/physiologie , Danio zébré , Phosphoprotein Phosphatases/génétique , Phosphoprotein Phosphatases/métabolismeRÉSUMÉ
Macroautophagy/autophagy is an essential pro-survival mechanism activated in response to nutrient deficiency. The proper fusion between autophagosomes and lysosomes is a critical step for autophagic degradation. We recently reported that RUNDC1 (RUN domain containing 1) inhibits autolysosome formation via clasping the ATG14-STX17-SNAP29 complex to hinder VAMP8 binding. We showed that RUNDC1 colocalizes with LC3 and associates with mature autophagosomes in cell lines and the zebrafish model. We utilized liposome fusion and in vitro autophagosome-lysosome fusion assays to demonstrate that RUNDC1 inhibits autolysosome formation. Moreover, we found that RUNDC1 clasps the ATG14-STX17-SNAP29 complex via stimulating ATG14 homo-oligomerization to inhibit ATG14 dissociation, which in turn prevents VAMP8 from binding to STX17-SNAP29. Our results demonstrate that RUNDC1 is a negative regulator of autophagy that restricts autophagosome fusion with lysosomes and is crucial for zebrafish survival in nutrient-deficient conditions. Here, we summarize our findings and discuss their implications for our understanding of autophagy regulation.
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Autophagosomes , Autophagie , Animaux , Autophagosomes/métabolisme , Autophagie/physiologie , Danio zébré/métabolisme , Facteurs de transcription/métabolisme , Lysosomes/métabolisme , Fusion membranaire/physiologie , Protéines SNARE/métabolismeRÉSUMÉ
PURPOSE: There are only a few case reports of laparoscopic lateral duodenojejunostomy (LLDJ) in children with Wilkie's syndrome, also known as superior mesenteric artery compression syndrome (SMAS). We aimed to describe our laparoscopic technique and evaluate its outcomes for SMAS in children. METHODS: From January 2013 to May 2021, SMAS children who received LLDJ were included. The procedure was carried out utilizing the four-trocar technique. The elevation of the transverse colon allows good exposure of the dilated and bulging second and third sections of the duodenum. Using a linear stapler, we established a lateral anastomosis connecting the proximal jejunum with the third part of the duodenum. Following that, a running suture was used to intracorporeally close the common enterotomy. Clinical data on patients was collected for analysis. The demographics, diagnostic findings, and postoperative outcomes were analyzed retrospectively. RESULTS: We retrospectively analyzed 9 SMAS patients (6 females and 3 males) who underwent LLDJ, aged between 7 and 17 years old. The mean operative time was 118.4 ± 16.5 min and the mean estimated blood loss was 5.6 ± 1.4 ml. There were no conversion, intraoperative complications or immediate postoperative complications. The mean postoperative hospital stay was 6.8 ± 1.9 days and the mean follow-up time was 5.4 ± 3.0 years. During follow-up, seven patients (77.8%) experienced complete recovery of symptoms prior to surgery. One patient (11.1%) still had mild vomiting, which resolved with medication. Another patient (11.1%) developed psychological-induced nausea, which significantly improved after treatment with education, training and diet management. CONCLUSIONS: LLDJ represents a feasible and safe treatment option for SMAS in well-selected children. Further evaluation with more cases and case-control studies is required for the real benefits.
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Laparoscopie , Syndrome de l'artère mésentérique supérieure , Mâle , Femelle , Humains , Enfant , Adolescent , Études rétrospectives , Artère mésentérique supérieure/chirurgie , Syndrome de l'artère mésentérique supérieure/chirurgie , Syndrome de l'artère mésentérique supérieure/diagnostic , Laparoscopie/méthodes , Anastomose chirurgicale/méthodesRÉSUMÉ
Over the past few decades, cellular senescence has been identified in cancer patients undergoing chemotherapy and radiotherapy. Senescent cells are generally characterized by permanent cell cycle arrest as a response to endogenous and exogenous stresses. In addition to exiting the cell cycle process, cellular senescence also triggers profound phenotypic changes such as senescence-associated secretory phenotype (SASP), autophagy modulation, or metabolic reprograming. Consequently, cellular senescence is often considered as a tumor-suppressive mechanism that permanently arrests cells at risk of malignant transformation. However, accumulating evidence shows that therapy-induced senescence can promote epithelial-mesenchymal transition and tumorigenesis in neighboring cells, as well as re-entry into the cell cycle and activation of cancer stem cells, thereby promoting cancer cell survival. Therefore, it is particularly important to rapidly eliminate therapy-induced senescent cells in patients with cancer. Here we review the hallmarks of cellular senescence and the relationship between cellular senescence and cancer. We also discuss several pathways to induce senescence in tumor therapy, as well as strategies to eliminate senescent cells after cancer treatment. We believe that exploiting the intersection between cellular senescence and tumor cells is an important means to defeat tumors.
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Autophagy serves as a pro-survival mechanism for a cell or a whole organism to cope with nutrient stress. Our understanding of the molecular regulation of this fusion event remains incomplete. Here, we identified RUNDC1 as a novel ATG14-interacting protein, which is highly conserved across vertebrates, including zebrafish and humans. By gain and loss of function studies, we demonstrate that RUNDC1 negatively modulates autophagy by blocking fusion between autophagosomes and lysosomes via inhibiting the assembly of the STX17-SNAP29-VAMP8 complex both in human cells and the zebrafish model. Moreover, RUNDC1 clasps the ATG14-STX17-SNAP29 complex via stimulating ATG14 homo-oligomerization to inhibit ATG14 dissociation. This also prevents VAMP8 from binding to STX17-SNAP29. We further identified that phosphorylation of RUNDC1 Ser379 is crucial to inhibit the assembly of the STX17-SNAP29-VAMP8 complex via promoting ATG14 homo-oligomerization. In line with our findings, RunDC1 is crucial for zebrafish in their response to nutrient-deficient conditions. Taken together, our findings demonstrate that RUNDC1 is a negative regulator of autophagy that restricts autophagosome fusion with lysosomes by clasping the ATG14-STX17-SNAP29 complex to hinder VAMP8 binding.
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The Wnt/ß-catenin signaling is usually abnormally activated in hepatocellular carcinoma (HCC), and pituitary tumor-transforming gene 1 (PTTG1) has been found to be highly expressed in HCC. However, the specific mechanism of PTTG1 pathogenesis remains poorly understood. Here, we found that PTTG1 is a bona fide ß-catenin binding protein. PTTG1 positively regulates Wnt/ß-catenin signaling by inhibiting the destruction complex assembly, promoting ß-catenin stabilization and subsequent nuclear localization. Moreover, the subcellular distribution of PTTG1 was regulated by its phosphorylation status. Among them, PP2A induced PTTG1 dephosphorylation at Ser165/171 residues and prevented PTTG1 translocation into the nucleus, but these effects were effectively reversed by PP2A inhibitor okadaic acid (OA). Interestingly, we found that PTTG1 decreased Ser9 phosphorylation-inactivation of GSK3ß by competitively binding to PP2A with GSK3ß, indirectly leading to cytoplasmic ß-catenin stabilization. Finally, PTTG1 was highly expressed in HCC and associated with poor patient prognosis. PTTG1 could promote the proliferative and metastasis of HCC cells. Overall, our results indicated that PTTG1 plays a crucial role in stabilizing ß-catenin and facilitating its nuclear accumulation, leading to aberrant activation of Wnt/ß-catenin signaling and providing a feasible therapeutic target for human HCC.
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Carcinome hépatocellulaire , Tumeurs du foie , Humains , Carcinome hépatocellulaire/anatomopathologie , Tumeurs du foie/anatomopathologie , Glycogen synthase kinase 3 beta/génétique , Glycogen synthase kinase 3 beta/métabolisme , bêta-Caténine/génétique , bêta-Caténine/métabolisme , Lignée cellulaire , Voie de signalisation Wnt/génétique , Lignée cellulaire tumoraleRÉSUMÉ
Macroautophagy is a health-modifying process of engulfing misfolded or aggregated proteins or damaged organelles, coating these proteins or organelles into vesicles, fusion of vesicles with lysosomes to form autophagic lysosomes, and degradation of the encapsulated contents. It is also a self-rescue strategy in response to harsh environments and plays an essential role in cancer cells. AMP-activated protein kinase (AMPK) is the central pathway that regulates autophagy initiation and autophagosome formation by phosphorylating targets such as mTORC1 and unc-51 like activating kinase 1 (ULK1). AMPK is an evolutionarily conserved serine/threonine protein kinase that acts as an energy sensor in cells and regulates various metabolic processes, including those involved in cancer. The regulatory network of AMPK is complicated and can be regulated by multiple upstream factors, such as LKB1, AKT, PPAR, SIRT1, or noncoding RNAs. Currently, AMPK is being investigated as a novel target for anticancer therapies based on its role in macroautophagy regulation. Herein, we review the effects of AMPK-dependent autophagy on tumor cell survival and treatment strategies targeting AMPK.
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AMP-Activated Protein Kinases , Tumeurs , AMP-Activated Protein Kinases/métabolisme , Protein-Serine-Threonine Kinases/métabolisme , Autophagie , Complexe-1 cible mécanistique de la rapamycine/métabolisme , Tumeurs/génétiqueRÉSUMÉ
Autophagy is a highly conserved recycling process of eukaryotic cells that degrades protein aggregates or damaged organelles with the participation of autophagy-related proteins. Membrane bending is a key step in autophagosome membrane formation and nucleation. A variety of autophagy-related proteins (ATGs) are needed to sense and generate membrane curvature, which then complete the membrane remodeling process. The Atg1 complex, Atg2-Atg18 complex, Vps34 complex, Atg12-Atg5 conjugation system, Atg8-phosphatidylethanolamine conjugation system, and transmembrane protein Atg9 promote the production of autophagosomal membranes directly or indirectly through their specific structures to alter membrane curvature. There are three common mechanisms to explain the change in membrane curvature. For example, the BAR domain of Bif-1 senses and tethers Atg9 vesicles to change the membrane curvature of the isolation membrane (IM), and the Atg9 vesicles are reported as a source of the IM in the autophagy process. The amphiphilic helix of Bif-1 inserts directly into the phospholipid bilayer, causing membrane asymmetry, and thus changing the membrane curvature of the IM. Atg2 forms a pathway for lipid transport from the endoplasmic reticulum to the IM, and this pathway also contributes to the formation of the IM. In this review, we introduce the phenomena and causes of membrane curvature changes in the process of macroautophagy, and the mechanisms of ATGs in membrane curvature and autophagosome membrane formation.
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Autophagosomes , Protéines associées à l'autophagie , Autophagie , Membrane cellulaire , Protéolyse , Membrane cellulaire/composition chimique , Membrane cellulaire/métabolisme , Agrégats de protéines , Autophagosomes/composition chimique , Autophagosomes/métabolisme , Protéines associées à l'autophagie/composition chimique , Protéines associées à l'autophagie/métabolisme , Domaines protéiques , Double couche lipidique , HumainsRÉSUMÉ
Transient receptor potential (TRP) polycystin-3 (TRPP3) is a non-selective cation channel activated by Ca2+ and protons and is involved in regulating ciliary Ca2+ concentration, hedgehog signaling and sour tasting. The TRPP3 channel function and regulation are still not well understood. Here we investigated regulation of TRPP3 by calmodulin (CaM) by means of electrophysiology and Xenopus oocytes as an expression model. We found that TRPP3 channel function is enhanced by calmidazolium, a CaM antagonist, and inhibited by CaM through binding of the CaM N-lobe to a TRPP3 C-terminal domain not overlapped with the EF-hand. We further revealed that the TRPP3/CaM interaction promotes phosphorylation of TRPP3 at threonine 591 by Ca2+/CaM-dependent protein kinase II, which mediates the inhibition of TRPP3 by CaM.
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Cellulosic ethanol is regarded as a perfect additive for petrol fuels for global carbon neutralization. As bioethanol conversion requires strong biomass pretreatment and overpriced enzymatic hydrolysis, it is increasingly considered in the exploration of biomass processes with fewer chemicals for cost-effective biofuels and value-added bioproducts. In this study, we performed optimal liquid-hot-water pretreatment (190 °C for 10 min) co-supplied with 4% FeCl3 to achieve the near-complete biomass enzymatic saccharification of desirable corn stalk for high bioethanol production, and all the enzyme-undigestible lignocellulose residues were then examined as active biosorbents for high Cd adsorption. Furthermore, by incubating Trichoderma reesei with the desired corn stalk co-supplied with 0.05% FeCl3 for the secretion of lignocellulose-degradation enzymes in vivo, we examined five secreted enzyme activities elevated by 1.3-3.0-fold in vitro, compared to the control without FeCl3 supplementation. After further supplying 1:2 (w/w) FeCl3 into the T. reesei-undigested lignocellulose residue for the thermal-carbonization process, we generated highly porous carbon with specific electroconductivity raised by 3-12-fold for the supercapacitor. Therefore, this work demonstrates that FeCl3 can act as a universal catalyst for the full-chain enhancement of biological, biochemical, and chemical conversions of lignocellulose substrates, providing a green-like strategy for low-cost biofuels and high-value bioproducts.
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Cellulase , Cellulase/métabolisme , Zea mays/composition chimique , Éthanol/métabolisme , Biocarburants , Lignine/métabolisme , Carbone , Hydrolyse , Biomasse , FermentationRÉSUMÉ
In this study, bacterial BsEXLE1 gene was overexpressed into T. reesei (Rut-C30) to generate a desirable engineered TrEXLX10 strain. While incubated with alkali-pretreated Miscanthus straw as carbon source, the TrEXLX10 secreted the ß-glucosidases, cellobiohydrolases and xylanses with activities raised by 34%, 82% and 159% compared to the Rut-C30. Supplying EXLX10-secreted crude enzymes and commercial mixed-cellulases for two-step lignocellulose hydrolyses of corn and Miscanthus straws after mild alkali pretreatments, this work measured consistently higher hexoses yields released by the EXLX10-secreted enzymes for synergistic enhancements of biomass saccharification in all parallel experiments examined. Meanwhile, this study detected that the expansin, purified from EXLX10-secreted solution, was of exceptionally high binding activities with wall polymers, and further determined its independent enhancement for cellulose hydrolysis. Therefore, this study raised a mechanism model to highlight EXLX/expansin dual-activation roles for both secretion of stable biomass-degradation enzymes at high activity and biomass enzymatic saccharification in bioenergy crops.