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1.
ACS Sens ; 9(10): 5135-5147, 2024 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-39400357

RESUMO

Branched-chain amino acids (BCAAs) play an important role in the functioning of mammalian cells and the central nervous system. However, available genetically encoded indicators for BCAAs are based on Förster resonance energy transfer and have a limited dynamic range. We developed a single fluorescent protein-based sensor for BCAAs, called NeIle, which is composed of circularly permutated mNeonGreen protein inserted into the leucine-isoleucine-valine binding protein (LIVBP) from Escherichia coli bacteria. In solution, the NeIle indicator displayed a positive fluorescence response to adding isoleucine, leucine, and valin amino acids with high ΔF/F dynamic ranges of 27-, 19-, and 11-fold and the corresponding affinity values of 5.0, 2.9, and 75 mM, respectively. The spectral and biochemical properties of the NeIle indicator were characterized in solution. We characterized the brightness of the NeIle indicator in living mammalian cells, including cultured neurons. Using the NeIle indicator, we successfully visualized the dynamics of isoleucine transients in different organelles of mammalian cells. We obtained and analyzed the X-ray crystal structure of the NeIle indicator in an isoleucine-bound state. Structure-guided directed mutagenesis of the NeIle indicator revealed the basis of its fluorescence response and selectivity to isoleucine.


Assuntos
Aminoácidos de Cadeia Ramificada , Humanos , Aminoácidos de Cadeia Ramificada/química , Aminoácidos de Cadeia Ramificada/metabolismo , Proteínas Luminescentes/química , Proteínas Luminescentes/genética , Proteínas Luminescentes/metabolismo , Transferência Ressonante de Energia de Fluorescência/métodos , Animais , Escherichia coli/genética , Escherichia coli/química , Proteínas de Escherichia coli/química , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Células HEK293
2.
Comput Struct Biotechnol J ; 25: 177-185, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-39328903

RESUMO

The advent of advanced coatings has transformed material functionalities, extending their roles from basic coverage and visual appeal to include unique properties such as self-healing, superior hydrophobicity, and antimicrobial action. However, the traditional dependency on petrochemical-derived materials for these coatings raises environmental concerns. This study proposes the use of renewable and alternative materials for coating development. We present the use of bioengineered spider silk-inspired protein (SSIP), produced through recombinant technology, as a viable, eco-friendly alternative due to their ease of processing under ambient pressure and the utilization of water as a solvent, alongside their exceptional physicochemical properties. Our research investigates the effects of different thermal treatments and protein concentrations on the mechanical strength and surface water repellency of coatings on silica bases. Our findings reveal a direct correlation between the temperature of heat treatment and the enhancements in surface hydrophobicity and mechanical strength, where elevated temperatures facilitate increased resistance to water and improved mechanical integrity. Consequently, we advocate SSIPs present a promising, sustainable choice for advanced coatings, providing a pathway to fine-tune coating recipes for better mechanical and hydrophobic properties with a reduced ecological footprint, finding potential uses in various fields such as electronics.

3.
3 Biotech ; 14(10): 243, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39323902

RESUMO

Hydrothermal pretreatments are commonly employed prior to the biotechnological conversion of lignocellulosic biomass (LCB) into value-added products, such as fuels and chemicals. However, the by-products of this pretreatment, including furaldehydes, lignin-derived phenolics, and carboxylic acids, can inhibit the enzymes and microbes used in the biotechnological process. In this study, LCB degrading enzymes of endophytic and litter fungi were screened for their tolerance to potential pretreatment-derived inhibitors. Several fungi produced endo- and exoglucanases that remained functional in the presence of lignocellulose-derived phenolics. Some were also active in the presence of tannic acid. Additionally, thermostable endoglucanase activity was observed in some fungi. The ability of some of these fungi to utilize furaldehyde inhibitors as a sole carbon source was also noted. The culture supernatants of the fungal strains were tested in hydrolysis experiments using microcrystalline cellulose as a substrate, in the presence of lignocellulose phenolics and tannic acid. With some strains, higher sugar yields were obtained in the hydrolysis of cellulose when phenolics were added. Our results highlight the need for more intensive exploration of endophytic and plant litter fungi for novel inhibitor-resistant cellulases for biofuel production. Supplementary Information: The online version contains supplementary material available at 10.1007/s13205-024-04087-3.

4.
Biomacromolecules ; 25(5): 3076-3086, 2024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38634234

RESUMO

Despite the wide range of analytical tools available for the characterization of cellulose, the in-depth characterization of inhomogeneous, layered cellulose fiber structures remains a challenge. When treating fibers or spinning man-made fibers, the question always arises as to whether the changes in the fiber structure affect only the surface or the entire fiber. Here, we developed an analysis tool based on the sequential limited dissolution of cellulose fiber layers. The method can reveal potential differences in fiber properties along the cross-sectional profile of natural or man-made cellulose fibers. In this analytical approach, carbonyl groups are labeled with a carbonyl selective fluorescence label (CCOA), after which thin fiber layers are sequentially dissolved with the solvent system DMAc/LiCl (9% w/v) and analyzed with size exclusion chromatography coupled with light scattering and fluorescence detection. The analysis of these fractions allowed for the recording of the changes in the chemical structure across the layers, resulting in a detailed cross-sectional profile of the different functionalities and molecular weight distributions. The method was optimized and tested in practice with LPMO (lytic polysaccharide monooxygenase)-treated cotton fibers, where it revealed the depth of fiber modification by the enzyme.


Assuntos
Celulose , Celulose/química , Fibra de Algodão , Cromatografia em Gel/métodos
5.
Int J Mol Sci ; 24(8)2023 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-37108063

RESUMO

Genome editing technologies that are currently available and described have a fundamental impact on the development of molecular biology and medicine, industrial and agricultural biotechnology and other fields. However, genome editing based on detection and manipulation of the targeted RNA is a promising alternative to control the gene expression at the spatiotemporal transcriptomic level without complete elimination. The innovative CRISPR-Cas RNA-targeting systems changed the conception of biosensing systems and also allowed the RNA effectors to be used in various applications; for example, genomic editing, effective virus diagnostic tools, biomarkers, transcription regulations. In this review, we discussed the current state-of-the-art of specific CRISPR-Cas systems known to bind and cleave RNA substrates and summarized potential applications of the versatile RNA-targeting systems.


Assuntos
Sistemas CRISPR-Cas , RNA , Sistemas CRISPR-Cas/genética , RNA/genética , Edição de Genes , Biotecnologia
6.
Biotechnol Biofuels Bioprod ; 15(1): 49, 2022 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-35568899

RESUMO

BACKGROUND: Enzymatic hydrolysis of lignocellulosic biomass into platform sugars can be enhanced by the addition of accessory enzymes, such as xylanases. Lignin from steam pretreated biomasses is known to inhibit enzymes by non-productively binding enzymes and limiting access to cellulose. The effect of enzymatically isolated lignin on the hydrolysis of xylan by four glycoside hydrolase (GH) family 11 xylanases was studied. Two xylanases from the mesophilic Trichoderma reesei, TrXyn1, TrXyn2, and two forms of a thermostable metagenomic xylanase Xyl40 were compared. RESULTS: Lignin isolated from steam pretreated spruce decreased the hydrolysis yields of xylan for all the xylanases at 40 and 50 °C. At elevated hydrolysis temperature of 50 °C, the least thermostable xylanase TrXyn1 was most inhibited by lignin and the most thermostable xylanase, the catalytic domain (CD) of Xyl40, was least inhibited by lignin. Enzyme activity and binding to lignin were studied after incubation of the xylanases with lignin for up to 24 h at 40 °C. All the studied xylanases bound to lignin, but the thermostable xylanases retained 22-39% of activity on the lignin surface for 24 h, whereas the mesophilic T. reesei xylanases become inactive. Removing of N-glycans from the catalytic domain of Xyl40 increased lignin inhibition in hydrolysis of xylan when compared to the glycosylated form. By comparing the 3D structures of these xylanases, features contributing to the increased thermal stability of Xyl40 were identified. CONCLUSIONS: High thermal stability of xylanases Xyl40 and Xyl40-CD enabled the enzymes to remain partially active on the lignin surface. N-glycosylation of the catalytic domain of Xyl40 increased the lignin tolerance of the enzyme. Thermostability of Xyl40 was most likely contributed by a disulphide bond and salt bridge in the N-terminal and α-helix regions.

7.
J Matern Fetal Neonatal Med ; 35(25): 9331-9335, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35086412

RESUMO

OBJECTIVE: to compare trans-cervical balloon catheter with oral administration of mifepristone for induction of labor. METHODS: Retrospective cohort study including a total of 325 patients; labor was induced with Foley catheter (group I, n = 220) or mifepristone (group II, n = 105). We selected patients with cervical ripening ≤5 cm according to Bishop score (n = 208) and divided into 2 subgroups depending on the parity: group I, primiparous with a Bishop score of ≤5, n = 70 - I (1, ≤5); group I, multiparous with a Bishop score of ≤5, n = 44 - I (2,≤5); group II, primiparous with a Bishop score of ≤5, n = 65 - II (1, ≤5); group II, multiparous with a Bishop score of ≤5, n = 29 - II (2, ≤5). Frequencies and percentages were presented using analysis of variance. RESULTS: Vaginal delivery occurred more frequently in patients induced by mifepristone (76.5%) vs. Foley catheter (74.5%). However, vaginal delivery within 24 h from the onset of induction occurred in the majority of patients in the Foley catheter groups: 39 (55.7%) and 28 (63.6%) versus 15 (23.1%) and 6 (20.7%) in groups induced with mifepristone. The frequency of cesarean section in the primiparas induced using a Foley catheter was 14%, with the use of mifepristone 21%. However, all multiparas induced with mifepristone delivered vaginally, in contrast to 30.7% of multiparas with the placement of a Foley catheter which required a cesarean delivery. CONCLUSION: Comparison of the effectiveness of induction of labor with the use of mifepristone and an intracervical balloon Foley catheter showed that both of these methods are successful, with more deliveries within the first 24 hrs achieved by using Foley catheter. The results of this study support the postulate that the success of an induction is largely dependent on the degree of cervical ripening and parity.


Assuntos
Mifepristona , Ocitócicos , Humanos , Gravidez , Feminino , Cesárea , Estudos de Coortes , Estudos Retrospectivos , Trabalho de Parto Induzido/métodos , Maturidade Cervical , Cateterismo Urinário/métodos , Cateteres Urinários
8.
J Matern Fetal Neonatal Med ; 35(11): 2174-2187, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32508168

RESUMO

BACKGROUND: COVID-19 is a pandemic disease caused by the SARS-CoV-2 and it spread globally in the last few months. The complete lack of specific treatment forced clinicians to use old drugs, chosen for their efficacy against similar viruses or their in vitro activity. Trials on patients are ongoing but the majority of information comes from small case series and single center reports. We aimed to provide a literature review on the putative effectiveness and safety of available treatments for COVID-19 in pregnant women. METHODS: We reviewed all the available literature concerning the drugs that have been used in the treatment of COVID-19 during pregnancy and whose safe assumption during pregnancy had been demonstrated by clinical studies (i.e. including studies on other infectious diseases). Drugs contra-indicated during pregnancy or with unknown adverse effects were not included in our review. RESULTS AND CONCLUSIONS: Clinical trials are not often conducted among pregnant patients for safety reasons and this means that drugs that may be effective in general population cannot be used for pregnant women due to the lack of knowledge of side effects in this category of people .The choice to use a specific drug for COVID-19 in pregnancy should take into account benefits and possible adverse events in each single case. In the current situation of uncertainty and poor knowledge about the management of COVID-19 during pregnancy, this present overview may provide useful information for physicians with practical implications.


Assuntos
Tratamento Farmacológico da COVID-19 , Complicações Infecciosas na Gravidez , Feminino , Humanos , Pandemias , Gravidez , Complicações Infecciosas na Gravidez/tratamento farmacológico , Complicações Infecciosas na Gravidez/epidemiologia , Gestantes , SARS-CoV-2
9.
J Matern Fetal Neonatal Med ; 35(14): 2663-2677, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32674641

RESUMO

Endometriosis is a disease that has a profound impact on the quality of life of women, due to the associated chronic pelvic pain, dysmenorrhea, dyspareunia and infertility. However, even getting long-awaited pregnancy (often after assisted reproductive technologies), patients with endometriosis have a high risk of obstetric complications, such as miscarriage, preterm birth, preeclampsia, placental abnormalities, hemorrhage in labor, birth of small for gestational age infants, stillbirth and higher cesarean section rate. In addition, during pregnancy acute complications of endometriosis may occur, such as spontaneous hemoperitoneum, which is rare but life-threatening conditions that in most cases require surgical intervention. The mechanisms of the observed complications in pregnant women with endometriosis are not fully understood. This review presents literature data and personal considerations on the effect of endometriosis on pregnancy outcome and the occurrence of complications, as well as their possible underlined mechanisms. Based on this, we proposed ways to reduce the risk of obstetric complications in pregnant women with a history of endometriosis.


Assuntos
Endometriose , Complicações na Gravidez , Nascimento Prematuro , Cesárea/efeitos adversos , Endometriose/complicações , Feminino , Humanos , Recém-Nascido , Placenta , Gravidez , Complicações na Gravidez/epidemiologia , Complicações na Gravidez/etiologia , Resultado da Gravidez/epidemiologia , Nascimento Prematuro/epidemiologia , Qualidade de Vida
10.
J Matern Fetal Neonatal Med ; 35(25): 5369-5374, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33522331

RESUMO

STUDY AIM: To evaluate the effects of the combination of Arabin pessary or cervical cerclage with vaginal micronised progesterone versus micronised progesterone or no medical management on the outcomes of pregnancies in women with large uterine fibroids. MATERIALS AND METHODS: This was a retrospective, observational, controlled study in 120 women aged 18-45 years with large uterine (≥8 cm) fibroids diagnosed in the first trimester, who underwent treatment in the regional perinatal center of the Omsk Regional Clinical Hospital between 2015 and 2019. Women in Group A (n = 90) were divided into two subgroups. In Subgroup А1 (n = 35), participants received the combination of a cervical procedure (Arabin pessary or cerclage) and micronised progesterone, and in Subgroup А2 (n = 55) all participants additionally underwent myomectomy. In Group B (n = 18), only micronised progesterone was used. In Group C (n = 12), no medical therapy was administered during pregnancy. RESULTS: Large uterine fibroids in pregnancy were associated with a threatened pregnancy loss in 46.4% of women and pain in almost 40% of women. Myomectomy in pregnancy was performed in 55 women. The combination of Arabin pessary or cervical cerclage with micronized progesterone reduced the rates of preterm delivery by 2.2-fold versus the progesterone-only group and by 11.2-fold versus no medical management group (χ2 = 19.4; p = .0001). CONCLUSION: The combination of Arabin pessary or cervical cerclage with micronized progesterone in our study helped achieve term deliveries in >90% of pregnant women with large fibroids.


Assuntos
Cerclagem Cervical , Leiomioma , Nascimento Prematuro , Recém-Nascido , Feminino , Gravidez , Humanos , Resultado da Gravidez/epidemiologia , Progesterona , Cerclagem Cervical/métodos , Pessários , Colo do Útero , Leiomioma/cirurgia
11.
Ultrasound Med Biol ; 47(8): 2220-2232, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33994230

RESUMO

Prematurity and intra-uterine growth restriction (IUGR) are risk factors for long-term poor neurodevelopmental outcomes and are associated with reductions in regional brain volumes. In this study, the aim was to determine the possible role of 3-D ultrasonography (3-DUS) volumes of whole brain, thalamus, frontal cortex and cerebellum, measured at postnatal days 30-40, as early predictors of long-term risk for neurobehavioral disorders. To this purpose, a heterogeneous population of full-term, preterm, IUGR and preterm IUGR (pre-IUGR) born individuals (n = 334), characterized by gestational age and birth weight in the ranges 24-41 wk and 860-4000 g, respectively, was followed from postnatal days 30-40 to the second year of life. At enrollment, brain volumes were measured using 3-DUS, whereas neurodevelopment was assessed at 2 y using the Griffiths III test. Cerebral volumes were strictly and significantly lower in infants characterized by a negative outcome and had excellent diagnostic accuracy. The 3-DUS volume of whole brain, thalamus, frontal cortex or cerebellum may be an early predictor of neonates at major risk for neurobehavioral disorders in later life.


Assuntos
Encéfalo/diagnóstico por imagem , Encéfalo/crescimento & desenvolvimento , Ecoencefalografia , Imageamento Tridimensional , Transtornos do Neurodesenvolvimento/epidemiologia , Seguimentos , Idade Gestacional , Humanos , Lactente , Recém-Nascido , Tamanho do Órgão , Valor Preditivo dos Testes , Estudos Prospectivos , Medição de Risco , Fatores de Tempo
12.
Int J Gynaecol Obstet ; 154(2): 277-284, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33471361

RESUMO

OBJECTIVE: To improve the management of patients with chronic endometritis (CE) by using a molded sorbent-modified by polyvinylpyrrolidone (FSMP). METHODS: This prospective study included 70 patients with CE divided into two groups: group 1 (n = 23) received traditional antibiotic therapy (from days 3 to 10 of the menstrual cycle); group 2 (n = 47), received antibiotics and FSMP was inserted from days 5 to 10. RESULTS: At the end of therapy, group 1 had massive growth of pathogenic microflora in 21.7%, moderate growth in 69.6%, and no growth in 8.7% of cases. In group 2, after combined therapy, massive growth was observed in 4.3%, moderate growth in 44.7%, and no growth in 51.0%. In group 2 after 5 days, serum levels of interleukin-1ß (IL-1ß) were 1.9 times, of IL-6 were 7.0 times, and of IL-8 and IL-1 receptor antagonist were 1.3 times lower than in group 1. In uterine cavity aspirates, IL-1ß decreased around 4.8 times, IL-6 by 11.8 times, IL-8 by 3.2 times, tumor necrosis factor-α by 3.9 times, and IL-1 receptor antagonist by 2.1 times in comparison to group 1. CONCLUSION: Combined therapy of FSMP with antibiotics is more effective in treating CE, because it contributes to the almost complete elimination of pathogens and toxins from the uterine cavity, blocking the local pro-inflammatory cascade.


Assuntos
Antibacterianos/administração & dosagem , Endometrite/terapia , Povidona/química , Adulto , Doença Crônica , Citocinas/sangue , Feminino , Humanos , Interleucina-1beta/sangue , Ciclo Menstrual , Estudos Prospectivos , Fator de Necrose Tumoral alfa/sangue
13.
Biopreserv Biobank ; 19(1): 73-82, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33058731

RESUMO

The research biobanking field is developing rapidly in Russia. Over the course of the last decade, numerous biobanks were created or formed from existing collections of human and environmental biospecimens. The Russian National Association of Biobanks and Biobanking Specialists (NASBIO) was established in December 2018, aiming to: (1) unite professionals and research centers to create and develop a network of biobanks in Russia; (2) provide services and expertise in the field of biobanking; (3) execute various research projects utilizing biobanks' infrastructure; and (4) facilitate integration of Russian biomedical research centers into global research activities. The organizational structure, aims, and plans of this newly formed national association are reviewed in this article. The founders of NASBIO hope that the association will promote further development of biobanks and their networking in Russia, which is critically important for the success of national biomedical, pharmaceutical, and biotechnological research, and can facilitate international biobanking projects on a global scale.


Assuntos
Bancos de Espécimes Biológicos , Pesquisa Biomédica , Humanos , Federação Russa , Especialização
14.
J Basic Microbiol ; 60(11-12): 971-982, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33103248

RESUMO

Endo-ß-xylanases are hemicellulases involved in the conversion of xylans in plant biomass. Here, we report a novel acidophilic ß-xylanase (ScXynA) with high transglycosylation abilities that was isolated from the filamentous fungus Scytalidium candidum 3C. ScXynA was identified as a glycoside hydrolase family 10 (GH10) dimeric protein, with a molecular weight of 38 ± 5 kDa per subunit. The enzyme catalyzed the hydrolysis of different xylans under acidic conditions and was stable in the pH range 2.6-4.5. The kinetic parameters of ScXynA were determined in hydrolysis reactions with p-nitrophenyl-ß-d-cellobioside (pNP-ß-Cel) and p-nitrophenyl-ß-d-xylobioside (pNP-ß-Xyl2 ), and kcat /Km was found to be 0.43 ± 0.02 (s·mM)-1 and 57 ± 3 (s·mM)-1 , respectively. In the catalysis of the transglycosylation o-nitrophenyl-ß-d-xylobioside (oNP-ß-Xyl2 ) acted both as a donor and an acceptor, resulting in the efficient production of o-nitrophenyl xylooligosaccharides, with a degree of polymerization of 3-10 and o-nitrophenyl-ß-d-xylotetraose (oNP-ß-Xyl4 ) as the major product (18.5% yield). The modeled ScXynA structure showed a favorable position for ligand entry and o-nitrophenyl group accommodation in the relatively open -3 subsite, while the cleavage site was covered with an extended loop. These structural features provide favorable conditions for transglycosylation with oNP-ß-Xyl2 . The acidophilic properties and high transglycosylation activity make ScXynA a suitable choice for various biotechnological applications, including the synthesis of valuable xylooligosaccharides.


Assuntos
Ascomicetos/enzimologia , Endo-1,4-beta-Xilanases/metabolismo , Glucuronatos/metabolismo , Oligossacarídeos/metabolismo , Catálise , Endo-1,4-beta-Xilanases/química , Endo-1,4-beta-Xilanases/isolamento & purificação , Glicosilação , Concentração de Íons de Hidrogênio , Hidrólise , Cinética , Modelos Moleculares , Peso Molecular , Multimerização Proteica , Especificidade por Substrato , Temperatura , Xilanos/metabolismo
15.
J Matern Fetal Neonatal Med ; 33(17): 2955-2960, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30614315

RESUMO

Aim: To assess the efficacy of a Zhukovsky obstetric double balloon for improving outcomes in women undergoing hysterectomy for postpartum hemorrhage.Materials and methods: This was a randomized controlled study. Participants were divided into two groups to undergo insertion of a Zhukovsky obstetric double balloon prior to hysterectomy (n = 16) or conventional hysterectomy (n = 25).Results: The main reasons for major obstetric hemorrhage were placenta accreta (53.6%), uterine atony (26.8%), uteroplacental apoplexy (14.6%), and amniotic fluid embolism (4.8%). The use of a Zhukovsky obstetric double balloon during postpartum hysterectomy was associated with a 1.7-fold reduction in blood loss and a 2.3-fold reduction in blood loss > 2000 ml compared with conventional hysterectomy.Conclusion: The use of a Zhukovsky obstetric double balloon represents a potent tool for improvement of immediate outcomes of hysterectomy in women with severe postpartum bleeding.


Assuntos
Placenta Acreta , Hemorragia Pós-Parto , Inércia Uterina , Cesárea , Feminino , Humanos , Histerectomia , Placenta Acreta/cirurgia , Hemorragia Pós-Parto/cirurgia , Período Pós-Parto , Gravidez , Estudos Retrospectivos , Inércia Uterina/cirurgia
16.
Biotechnol Biofuels ; 12: 235, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31624497

RESUMO

BACKGROUND: Enzyme-aided valorization of lignocellulose represents a green and sustainable alternative to the traditional chemical industry. The recently discovered lytic polysaccharide monooxygenases (LPMOs) are important components of the state-of-the art enzyme cocktails for cellulose conversion. Yet, these monocopper enzymes are poorly characterized in terms of their kinetics, as exemplified by the growing evidence for that H2O2 may be a more efficient co-substrate for LPMOs than O2. LPMOs need external electron donors and one key question of relevance for bioprocess development is whether the required reducing power may be provided by the lignocellulosic substrate. RESULTS: Here, we show that the liquid fraction (LF) resulting from hydrothermal pretreatment of wheat straw supports LPMO activity on both chitin and cellulose. The initial, transient activity burst of the LPMO reaction was caused by the H2O2 present in the LF before addition of LPMO, while the steady-state rate of LPMO reaction was limited by the LPMO-independent production of H2O2 in the LF. H2O2 is an intermediate of LF oxidation as evidenced by a slow H2O2 accumulation in LF, despite high H2O2 production rates. This H2O2 scavenging ability of LF is important since high concentrations of H2O2 may lead to irreversible inactivation of LPMOs. CONCLUSIONS: Our results support the growing understanding that fine-tuned control over the rates of H2O2 production and consumption in different, enzymatic and non-enzymatic reactions is essential for harnessing the full catalytic potential of LPMOs in lignocellulose valorization.

17.
Clin Mass Spectrom ; 13: 21-26, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34841082

RESUMO

Endometriosis is a recurrent and benign gynecological disorder, defined by the ectopic presence of endometrium. About 10% of reproductive-aged women suffer from endometriosis. There are no non-invasive or minimally invasive tests available in clinical practice to accurately diagnose endometriosis today. Here, we present our efforts to determine the diagnostic accuracy of biomarkers in peritoneal fluid and blood plasma using flow injection analysis with electrospray ionization tandem mass spectrometry (ESI-MS/MS) in 70 women with endometriosis and 20 women from a control group. The presence of endometriosis was confirmed by surgical findings and post-operative pathological examination. A qualitative and quantitative evaluation of the lipids in peritoneal fluids and blood plasma was carried out using electrospray ionization mass spectrometry (ESI-MS). The analysis revealed more than 140 molecular species of lipids, most of which pertained to five classes: phosphatidylcholines, phosphatidylethanolamines, sphingomyelins, di- and triglycerides. The data were analyzed using a statistical multifactorial method (i.e., PLS-DA). It was found that 9 potential biomarkers of endometriosis (LPC 16:0, PE O-20:0, PE O 34:1, PC 36:2, PC 36:4, PC 36:5, PC 38:4, PC 38:6 and SM 34:1) are common in blood plasma and peritoneal fluid, supporting connection with the pathological process. The sensitivity of the method developed for plasma was 93% with a specificity of 95%; for peritoneal fluid, the sensitivity was 90% and the specificity 95%. Accordingly, plasma is the most suitable biological fluid for clinical diagnostics of endometriosis. Further validation of these lipids as serologic biomarkers may enhance non-invasive diagnostic tools for patients with suspected endometriosis and reduce the frequency of diagnostic laparoscopy.

18.
Biotechnol Biofuels ; 11: 5, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29344086

RESUMO

BACKGROUND: The ascomycete fungus Trichoderma reesei is the predominant source of enzymes for industrial conversion of lignocellulose. Its glycoside hydrolase family 7 cellobiohydrolase (GH7 CBH) TreCel7A constitutes nearly half of the enzyme cocktail by weight and is the major workhorse in the cellulose hydrolysis process. The orthologs from Trichoderma atroviride (TatCel7A) and Trichoderma harzianum (ThaCel7A) show high sequence identity with TreCel7A, ~ 80%, and represent naturally evolved combinations of cellulose-binding tunnel-enclosing loop motifs, which have been suggested to influence intrinsic cellobiohydrolase properties, such as endo-initiation, processivity, and off-rate. RESULTS: The TatCel7A, ThaCel7A, and TreCel7A enzymes were characterized for comparison of function. The catalytic domain of TatCel7A was crystallized, and two structures were determined: without ligand and with thio-cellotriose in the active site. Initial hydrolysis of bacterial cellulose was faster with TatCel7A than either ThaCel7A or TreCel7A. In synergistic saccharification of pretreated corn stover, both TatCel7A and ThaCel7A were more efficient than TreCel7A, although TatCel7A was more sensitive to thermal inactivation. Structural analyses and molecular dynamics (MD) simulations were performed to elucidate important structure/function correlations. Moreover, reverse conservation analysis (RCA) of sequence diversity revealed divergent regions of interest located outside the cellulose-binding tunnel of Trichoderma spp. GH7 CBHs. CONCLUSIONS: We hypothesize that the combination of loop motifs is the main determinant for the observed differences in Cel7A activity on cellulosic substrates. Fine-tuning of the loop flexibility appears to be an important evolutionary target in Trichoderma spp., a conclusion supported by the RCA data. Our results indicate that, for industrial use, it would be beneficial to combine loop motifs from TatCel7A with the thermostability features of TreCel7A. Furthermore, one region implicated in thermal unfolding is suggested as a primary target for protein engineering.

19.
J Am Soc Mass Spectrom ; 29(2): 323-330, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-28956319

RESUMO

Recent research revealed that tissue spray mass spectrometry enables rapid molecular profiling of biological tissues, which is of great importance for the search of disease biomarkers as well as for online surgery control. However, the payback for the high speed of analysis in tissue spray analysis is the generally lower chemical sensitivity compared with the traditional approach based on the offline chemical extraction and electrospray ionization mass spectrometry detection. In this study, high resolution mass spectrometry analysis of endometrium tissues of different localizations obtained using direct tissue spray mass spectrometry in positive ion mode is compared with the results of electrospray ionization analysis of lipid extracts. Identified features in both cases belong to three lipid classes: phosphatidylcholines, phosphoethanolamines, and sphingomyelins. Lipids coverage is validated by hydrophilic interaction liquid chromatography with mass spectrometry of lipid extracts. Multivariate analysis of data from both methods reveals satisfactory differentiation of eutopic and ectopic endometrium tissues. Overall, our results indicate that the chemical information provided by tissue spray ionization is sufficient to allow differentiation of endometrial tissues by localization with similar reliability but higher speed than in the traditional approach relying on offline extraction. Graphical Abstract ᅟ.


Assuntos
Endométrio/química , Lipídeos/análise , Espectrometria de Massas por Ionização por Electrospray/métodos , Cromatografia Líquida/métodos , Endometriose/patologia , Endométrio/patologia , Feminino , Humanos , Interações Hidrofóbicas e Hidrofílicas , Fosfatidilcolinas/análise , Fosfatidiletanolaminas/análise , Esfingomielinas/análise
20.
J Minim Invasive Gynecol ; 25(3): 426-433, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-28888701

RESUMO

STUDY OBJECTIVE: To introduce a method for the rapid assessment of endometriotic tissues using direct mass spectrometry (MS)-based lipidomics. DESIGN: A prospective observational cohort study (Canadian Task Force classification II2). SETTING: Department of Operative Gynecology of the Research Centre for Obstetrics, Gynecology and Perinatology. PATIENTS: Fifty patients with ovarian cysts and peritoneal endometriosis who underwent laparoscopic surgery between 2014 and 2016. INTERVENTION: Differences in mass spectrometric profiles of ectopic endometria (endometriosis) and eutopic endometria were analyzed for each patient in combination with morphohistologic evaluation. The lipidomic approach was applied using a direct high-resolution MS method. MEASUREMENTS AND MAIN RESULTS: Of 148 metabolites, 15 showed significant differences between endometriotic tissue and a healthy endometrium of the same patient, considered as a control in this study. The main lipids prevalent in endometriotic tissues were phosphoethanolamine (PE O-20:0), sphingomyelin (SM 34:1), diglycerides (DG 44:9), phosphatidylcholines (PC 32:1, PC O-36:3, PC 38:7, PC 38:6, PC 40:8, PC 40:7, PC 40:6, PC 40:9, and PC O-42:1), and triglycerides (TG 41:2, TG 49:4, and TG 52:3). Using partial least squares discriminant analysis models, MS showed that the lipidomic profile of endometriotic tissue (peritoneal endometriosis and ovarian endometriomas) was clearly separated from the eutopic endometrium, indicating tissue-type differentiation. CONCLUSION: Our results suggest that direct MS may play an important role for endometriotic tissue identification. Such an approach has potential usefulness for real-time tissue determination and differentiation during surgical treatment. Lipids of 3 important classes, sphingolipids, phospholipids, and the fatty acids (di- and triglycerides), were identified. Validation is required to determine whether these lipids can be used to discriminate between patients with endometriosis and those with other gynecologic diseases.


Assuntos
Endometriose/patologia , Cistos Ovarianos/patologia , Adolescente , Adulto , Estudos de Coortes , Diagnóstico Diferencial , Endometriose/cirurgia , Endométrio/patologia , Endométrio/cirurgia , Feminino , Humanos , Metabolismo dos Lipídeos/fisiologia , Espectrometria de Massas/métodos , Pessoa de Meia-Idade , Cistos Ovarianos/cirurgia , Estudos Prospectivos , Adulto Jovem
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