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1.
Int J Biol Macromol ; 270(Pt 1): 131968, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38704059

ABSTRACT

Enzymatic degradation of lignocellulosic biomass provides an eco-friendly approach to produce value-added macromolecules, e.g., bioactive polysaccharides. A novel acidophilic GH5 ß-1,4-endoglucanase (termed TaCel5) from Trichoderma asperellum ND-1 was efficiently expressed in Komagataella phaffii (∼1.5-fold increase, 38.42 U/mL). TaCel5 displayed both endoglucanase (486.3 U/mg) and alginate lyase (359.5 U/mg) enzyme activities. It had optimal pH 3.0 and strong pH stability (exceed 86 % activity retained over pH range 3.0-5.0). 80 % activity (both endoglucanase and alginate lyase) was retained in the presence of 15 % ethanol or 3.42 M NaCl. Analysis of action mode revealed that hydrolytic activity of TaCel5 required at least three glucose (cellotriose) residues, yielding mainly cellobiose. Glu241 and Glu352 are essential catalytic residues, while Asp106, Asp277 and Asp317 play auxiliary roles in cellulose degradation. TaCel5 displayed high hydrolysis efficiency for glucan and alginate substrates. ESI-MS analysis indicated that the enzymatic hydrolysates of alginate mainly contained disaccharides and heptasaccharides. This is the first detailed report of a bifunctional GH5 endoglucanase/alginate lyase enzyme from T. asperellum. Thus TaCel5 has strong potential in food and feed industries as a catalyst for bioconversion of cellulose- and alginate-containing waste materials into value-added products oligosaccharides, which was of great benefit both for the economy and environment.


Subject(s)
Alginates , Cellulase , Cellulose , Oligosaccharides , Alginates/metabolism , Alginates/chemistry , Cellulase/metabolism , Cellulase/chemistry , Oligosaccharides/metabolism , Oligosaccharides/chemistry , Hydrolysis , Cellulose/metabolism , Hydrogen-Ion Concentration , Hypocreales/enzymology , Substrate Specificity , Polysaccharide-Lyases/metabolism , Polysaccharide-Lyases/chemistry , Polysaccharide-Lyases/genetics
2.
Eur J Oncol Nurs ; 70: 102537, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38484619

ABSTRACT

OBJECTIVE: This study aims to explore the intervention effects of narrative nursing on the reproductive concerns of cervical cancer patients of childbearing age undergoing surgical treatment. METHODS: Patients undergoing cervical cancer surgery with moderate to severe levels of reproductive concerns, treated between January and December 2023 at a tertiary Grade-A oncology hospital in China, were selected as the research subjects. Patients were randomized into an intervention group and a control group, each consisting of 33 patients. The control group received standard nursing care, while the intervention group received a narrative nursing intervention in addition to standard care. The changes in the levels of reproductive concerns, post-traumatic growth, and quality of life scores before and after the intervention were compared between the two groups. RESULTS: After the intervention, the reproductive concerns scores of the cervical cancer patients in the intervention group (32.53 ± 4.77) were significantly lower than those in the control group (59.29 ± 3.24), with a statistically significant difference (t = 26.143, p < 0.001). The post-traumatic growth scores in the intervention group (86.78 ± 3.52) were significantly higher than those in the control group (68.06 ± 6.24), with a statistically significant difference (t = -14.595, p < 0.001). The quality of life scores in the intervention group (149.00 [IQR = 8.75]) were significantly higher than those in the control group (129.00 [IQR = 13.00]), with a statistically significant difference (z = -5.799, p < 0.001). CONCLUSION: Narrative nursing can effectively alleviate reproductive concerns in cervical cancer patients undergoing surgical treatment, promote positive psychological changes post-trauma, and improve patients' quality of life.


Subject(s)
Quality of Life , Uterine Cervical Neoplasms , Humans , Female , Uterine Cervical Neoplasms/surgery , Adult , China , Middle Aged , Narrative Therapy/methods
3.
Int J Biol Macromol ; 254(Pt 1): 127650, 2024 Jan.
Article in English | MEDLINE | ID: mdl-38287580

ABSTRACT

A novel acidophilic GH5 ß-1,4-endoglucanase (TaCel12) from Trichoderma asperellum ND-1 was efficiently expressed in Pichia pastoris (a 1.5-fold increase). Deglycosylated TaCel12 migrated as a single band (26.5 kDa) in SDS-PAGE. TaCel12 was acidophilic with a pH optimum of 4.0 and displayed great pH stability (>80 % activity over pH 3.0-5.0). TaCel12 exhibited considerable activity towards sodium carboxymethyl cellulose and sodium alginate with Vmax values of 197.97 µmol/min/mg and 119.06 µmol/min/mg, respectively. Moreover, TaCel12 maintained >80 % activity in the presence of 20 % ethanol and 4.28 M NaCl. Additionally, Mn2+, Pb2+ and Cu2+ negatively affected TaCel12 activity, while the presence of 5 mM Co2+ significantly increased the enzyme activity. Analysis of action mode revealed that TaCel12 required at least four glucose (cellotetraose) residues for hydrolysis to yield cellobiose and cellotriose. Site-directed mutagenesis results suggested that Glu133 and Glu217 of TaCel12 are crucial catalytic residues, with Asp116 displaying an auxiliary function. Production of soluble sugars from lignocellulose is a crucial step in bioethanol development, and it is noteworthy that TaCel12 could synergistically yield fermentable sugars from corn stover and bagasse, respectively. Thus TaCel12 with excellent properties will be considered a potential biocatalyst for applications in various industries, especially for lignocellulosic biomass conversion.


Subject(s)
Cellulase , Hypocreales , Lignin , Trichoderma , Hydrolysis , Cellulase/genetics , Ethanol , Biomass , Cellobiose , Trichoderma/genetics
4.
Bioresour Technol ; 394: 130249, 2024 Feb.
Article in English | MEDLINE | ID: mdl-38154735

ABSTRACT

Effective production of xylooligosaccharides (XOS) with lower proportion of xylose entails unique and robust xylanases. In this study, two novel xylanases from Trichoderma asperellum ND-1 belonging to glycoside hydrolase families 10 (XynTR10) and 11 (XynTR11) were over-expressed in Komagataella phaffii X-33 and characterized to be robust enzymes with high halotolerance and ethanol tolerant. Both enzymes displayed strict substrate specificity towards beechwood xylan and wheat arabinoxylan. (Glu153/Glu258) and (Glu161/Glu252) were key catalytic sites for XynTR10 and XynTR11. Notably, XynTR11 could rapidly degrade xylan/XOS into xylobiose without xylose via transglycosylation. Direct degradation of corncob using XynTR10 and XynTR111 displayed that while XynTR10 yielded 77% xylobiose and 25% xylose, XynTR11 yielded much less xylose (11%) and comparable amounts of xylobiose (63%). XynTR10 or XynTR111 has great potential as a catalyst for bioconversion of xylan-containing agricultural waste into high-value products (biofuel or XOS), which is of significant benefit for the economy and environment.


Subject(s)
Glucuronates , Glycoside Hydrolases , Hypocreales , Xylans , Humans , Xylans/metabolism , Glycoside Hydrolases/metabolism , Zea mays/metabolism , Xylose/metabolism , Endo-1,4-beta Xylanases/genetics , Endo-1,4-beta Xylanases/metabolism , Oligosaccharides/metabolism , Hydrolysis , Substrate Specificity
5.
Cancer Med ; 12(24): 22224-22251, 2023 12.
Article in English | MEDLINE | ID: mdl-38069669

ABSTRACT

AIM: The aim of this study was to synthesize qualitative research evidence on cancer survivors' experiences with reproductive concerns (RC). METHODS: We conducted a systematic search of qualitative studies and utilized the meta-aggregation approach. The database searches were extended up to May 14, 2023, encompassing 12 databases, specifically MEDLINE, CINAHL, PubMed, EMBASE, Scopus, Web of Science (Core Collection), AMED, PsycINFO, The Cochrane Library, CNKI, Wan Fang Data, and VIP. RESULTS: Three overarching themes were synthesized from the analysis of 21 studies that explored cancer patients' awareness of reproductive concerns, their perceptions, needs, and coping styles. These themes encapsulate the multifaceted aspects of cancer patients' reproductive concerns: "Gender differences in fertility concerns among cancer patients: Perspectives from men and women"; "The influence of age: Experiences with fertility issues among cancer patients at different life stages"; "The impact of treatment stages on fertility concerns: The evolution of perception and coping strategies in the course of cancer treatment". CONCLUSION: Our study presents an in-depth exploration of the reproductive concerns experienced by cancer patients from various perspectives. We found that the internal experiences of reproductive concerns, their perceptions, needs, and coping mechanisms differ based on their roles. This comprehensive understanding of the complex emotions and needs of cancer patients when confronted with fertility issues can guide clinicians in providing more effective medical assistance, psychological counseling, and fertility-related information services.


Subject(s)
Cancer Survivors , Neoplasms , Male , Humans , Female , Cancer Survivors/psychology , Qualitative Research , Neoplasms/therapy , Neoplasms/psychology , Fertility , Counseling
6.
Front Bioeng Biotechnol ; 11: 1244772, 2023.
Article in English | MEDLINE | ID: mdl-37744260

ABSTRACT

Mannan, a highly abundant and cost-effective natural resource, holds great potential for the generation of high-value compounds such as bioactive polysaccharides and biofuels. In this study, we successfully enhanced the expression of constructed GH5 ß-mannanase (TaMan5) from Trichoderma asperellum ND-1 by employing propeptide in Pichia pastoris. By replacing the α-factor with propeptide (MGNRALNSMKFFKSQALALLAATSAVA), TaMan5 activity was significantly increased from 67.5 to 91.7 U/mL. It retained higher activity in the presence of 20% ethanol and 15% NaCl. When incubated with a high concentration of mannotriose or mannotetraose, the transglycosylation action of TaMan5 can be detected, yielding the corresponding production of mannotetraose or mannooligosaccharides. Moreover, the unique mechanism whereby TaMan5 catalyzes the degradation of mannan into mannobiose involves the transglycosylation of mannose to mannotriose or mannotetraose as a substrate to produce a mannotetraose or mannopentose intermediate, respectively. Additionally, the production of soluble sugars from lignocellulose is a crucial step in bioethanol development, and it is noteworthy that TaMan5 could synergistically yield fermentable sugars from corn stover and bagasse. These findings offered valuable insights and strategies for enhancing ß-mannanase expression and efficient conversion of lignocellulosic biomass, providing cost-effective and sustainable approaches for high-value biomolecule and biofuel production.

7.
Front Microbiol ; 14: 1191553, 2023.
Article in English | MEDLINE | ID: mdl-37362936

ABSTRACT

In this study, an acidophilic GH5 ß-mannanase (TaMan5) from Trichoderma asperellum ND-1 was efficiently expressed in Pichia pastoris (a 2.0-fold increase, 67.5 ± 1.95 U/mL). TaMan5 displayed the highest specificity toward locust bean gum (Km = 1.34 mg/mL, Vmax = 749.14 µmol/min/mg) at pH 4.0 and 65°C. Furthermore, TaMan5 displayed remarkable tolerance to acidic environments, retaining over 80% of its original activity at pH 3.0-5.0. The activity of TaMan5 was remarkably decreased by Cu2+, Mn2+, and SDS, while Fe2+/Fe3+ improved the enzyme activity. A thin-layer chromatography (TLC) analysis of the action model showed that TaMan5 could rapidly degrade mannan/MOS into mannobiose without mannose via hydrolysis action as well as transglycosylation. Site-directed mutagenesis results suggested that Glu205, Glu313, and Asp357 of TaMan5 are crucial catalytic residues, with Asp152 playing an auxiliary function. Additionally, TaMan5 and commercial α-galactosidase displayed a remarkable synergistic effect on the degradation of galactomannans. This study provided a novel ß-mannanase with ideal characteristics and can be considered a potential candidate for the production of bioactive polysaccharide mannobiose.

8.
Front Microbiol ; 13: 998160, 2022.
Article in English | MEDLINE | ID: mdl-36199370

ABSTRACT

Acidophilic ß-xylanases have attracted considerable attention due to their excellent activity under extreme acidic environments and potential industrial utilizations. In this study, a novel ß-xylanase gene (Xyl11) of glycoside hydrolase family 11, was cloned from Trichoderma asperellum ND-1 and efficiently expressed in Pichia pastoris (a 2.0-fold increase). Xyl11 displayed a maximum activity of 121.99 U/ml at pH 3.0 and 50°C, and exhibited strict substrate specificity toward beechwood xylan (K m = 9.06 mg/ml, V max = 608.65 µmol/min/mg). The Xyl11 retained over 80% activity at pH 2.0-5.0 after pretreatment at 4°C for 1 h. Analysis of the hydrolytic pattern revealed that Xyl11 could rapidly convert xylan to xylobiose via hydrolysis activity as well as transglycosylation. Moreover, the results of site-directed mutagenesis suggested that the Xyl11 residues, Glu127, Glu164, and Glu216, are essential catalytic sites, with Asp138 having an auxiliary function. Additionally, a high degree of synergy (15.02) was observed when Xyl11 was used in association with commercial ß-xylosidase. This study provided a novel acidophilic ß-xylanase that exhibits excellent characteristics and can, therefore, be considered a suitable candidate for extensive applications, especially in food and animal feed industries.

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