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1.
Environ Dev Sustain ; : 1-21, 2023 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-37363034

RESUMO

The component of human life that has been most significantly altered by the COVID-19 epidemic is travel. Due to the upheaval produced by the pandemic breakout, countries are becoming increasingly avaricious and are scrambling to stockpile vaccines. The world has been locked down to reduce/control the pandemic outbreak, driving countries to shut their doors to other people from countries. The recent pandemic has had a short-term, positive effect on the environment, but travel restrictions have caused problems for the common person and are expected to deteriorate more soon, necessitating longer quarantines, vaccination requirements, vaccine passports, and immunization certificates required by countries for safe travel. Thus, this study has three objectives. First, we investigate the impact of COVID-19 on travel and the environment, as well as the role that tourists play in the transmission of the virus. Second, we examine how countries are handling COVID-19 vaccines. Finally, we pinpoint differences in vaccination coverage.

2.
Extremophiles ; 22(1): 109-119, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29170828

RESUMO

A novel, family GH10 enzyme, Xyn10B from Acidothermus cellulolyticus 11B was cloned and expressed in Escherichia coli. This enzyme was purified to homogeneity by binding to regenerated amorphous cellulose. It had higher binding on Avicel as compared to insoluble xylan due to the presence of cellulose-binding domains, CBM3 and CBM2. This enzyme was optimally active at 70 °C and pH 6.0. It was stable up to 70 °C while the CD spectroscopy analysis showed thermal unfolding at 80 °C. Xyn10B was found to be a trifunctional enzyme having endo-xylanase, arabinofuranosidase and acetyl xylan esterase activities. Its activities against beechwood xylan, p-Nitrophenyl arabinofuranoside and p-Nitrophenyl acetate were found to be 126,480, 10,350 and 17,250 U µmol-1, respectively. Xyn10B was highly active producing xylobiose and xylose as the major end products, as well as debranching the substrates by removing arabinose and acetyl side chains. Due to its specific characteristics, this enzyme seems to be of importance for industrial applications such as pretreatment of poultry cereals, bio-bleaching of wood pulp and degradation of plant biomass.


Assuntos
Acetilesterase/metabolismo , Actinobacteria/enzimologia , Proteínas de Bactérias/metabolismo , Endo-1,4-beta-Xilanases/metabolismo , Glicosídeo Hidrolases/metabolismo , Acetilesterase/química , Proteínas de Bactérias/química , Endo-1,4-beta-Xilanases/química , Glicosídeo Hidrolases/química , Especificidade por Substrato
3.
Appl Microbiol Biotechnol ; 99(16): 6791-801, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26124068

RESUMO

This study shows expression of recombinant ovine growth hormone (roGH) and targeting to the inner membrane using signal sequence, DsbA, in Escherichia coli (E. coli) cell. Factors such as temperature, IPTG induction, and expression conditions were studied and show diverse optical density with different media compositions. The optimum expression level of roGH in terrific broth medium was at 25 °C on induction with 20 µM IPTG in early logarithmic phase. SDS-PAGE analysis of expression and subcellular fractions of recombinant constructs revealed the translocation of roGH to the inner membrane of E. coli with DsbA signal sequence at the N terminus of roGH. The protein was easily solubilized by 40 % acetonitrile with ~90 % purity and was identified by Western blot, and analysis on MALDI-TOF/TOF confirmed a size of 21,059 Da. Relatively high soluble protein yield of 65.3 mg/L of roGH was obtained. The biological function of roGH was confirmed by HeLa cell line proliferation. This is the first study describing achievement of biologically active soluble roGH targeted to the inner membrane of E. coli and rapid purification with high yield.


Assuntos
Membrana Celular/metabolismo , Proteínas de Escherichia coli/genética , Escherichia coli/metabolismo , Hormônio do Crescimento/isolamento & purificação , Hormônio do Crescimento/metabolismo , Isomerases de Dissulfetos de Proteínas/genética , Proteínas Recombinantes de Fusão/metabolismo , Animais , Western Blotting , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Eletroforese em Gel de Poliacrilamida , Células Epiteliais/efeitos dos fármacos , Escherichia coli/genética , Expressão Gênica , Cabras , Hormônio do Crescimento/química , Hormônio do Crescimento/genética , Humanos , Peso Molecular , Sinais Direcionadores de Proteínas , Proteínas Recombinantes de Fusão/química , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/isolamento & purificação , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Temperatura , Fatores de Tempo , Ativação Transcricional
4.
Int J Biol Macromol ; 256(Pt 1): 128387, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38000593

RESUMO

Alpha amylases catalyse the hydrolysis of α-1, 4-glycosidic bonds in starch, yielding glucose, maltose, dextrin, and short oligosaccharides, vital to various industrial processes. Structural and functional insights on α-amylase from Methanocaldococcus jannaschii were computationally explored to evaluate a catalytic domain and its fusion with a small ubiquitin-like modifier (SUMO). The recombinant proteins' production, characterization, ligand binding studies, and structural analysis of the cloned amylase native full gene (MjAFG), catalytic domain (MjAD) and fusion enzymes (S-MjAD) were thoroughly analysed in this comparative study. The MjAD and S-MjAD showed 2-fold and 2.5-fold higher specific activities (µmol min-1 mg -1) than MjAFG at 95 °C at pH 6.0. Molecular modelling and MD simulation results showed that the removal of the extra loop (178 residues) at the C-terminal of the catalytic domain exposed the binding and catalytic residues near its active site, which was buried in the MjAFG enzyme. The temperature ramping and secondary structure analysis of MjAFG, MjAD and S-MjAD through CD spectrometry showed no notable alterations in the secondary structures but verified the correct folding of MjA variants. The chimeric fusion of amylases with thermostable α-glucosidases makes it a potential candidate for the starch degrading processes.


Assuntos
Methanocaldococcus , alfa-Amilases , alfa-Amilases/química , Methanocaldococcus/metabolismo , Archaea/metabolismo , Amilases/química , Amido/metabolismo
5.
Carbohydr Res ; 539: 109122, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38657354

RESUMO

The genomic screening of hyper-thermophilic Pyrococcus abyssi showed uncharacterized novel α-amylase sequences. Homology modelling analysis revealed that the α-amylase from P. abyssi consists of an N-terminal GH57 catalytic domain, α-amylase central, and C-terminal domain. Current studies emphasize in-silico structural and functional analysis, recombinant expression, characterization, structural studies through CD spectroscopy, and ligand binding studies of the novel α-amylase from P. abyssi. The soluble expression of PaAFG was observed in the E. coli Rosetta™ (DE3) pLysS strain upon incubation overnight at 18 °C in an orbital shaker. The optimum temperature and pH of the PaAFG were observed at 90 °C in 50 mM phosphate buffer pH 6. The Km value for PaAFG against wheat starch was determined as 0.20 ± 0.053 mg while the corresponding Vmax value was 25.00 ± 0.67 µmol min-1 mg-1 in the presence of 2 mM CaCl2 and 12.5 % glycerol. The temperature ramping experiments through CD spectroscopy reveal no significant change in the secondary structures and positive and negative ellipticities of the CD spectra showing the proper folding and optimal temperature of PaAFG protein. The RMSD and RMSF of the PaAFG enzyme determined through molecular dynamic simulation show the significant protein's stability and mobility. The soluble production, thermostability and broad substrate specificity make this enzyme a promising choice for various industrial applications.


Assuntos
Pyrococcus abyssi , Amido , alfa-Amilases , alfa-Amilases/metabolismo , alfa-Amilases/química , alfa-Amilases/genética , Estabilidade Enzimática , Concentração de Íons de Hidrogênio , Modelos Moleculares , Pyrococcus abyssi/enzimologia , Amido/metabolismo , Amido/química , Temperatura
6.
Int J Biol Macromol ; 266(Pt 2): 131310, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38569986

RESUMO

Alpha amylase belonging to starch hydrolyzing enzymes has significant contributions to different industrial processes. The enzyme production through recombinant DNA technology faces certain challenges related to their expression, solubility and purification, which can be overcome through fusion tags. This study explored the influence of SUMO, a protein tag reported to enhance the solubility and stability of target proteins when fused to the N-terminal of the catalytic domain of amylase from Pyrococcus abyssi (PaAD). The insoluble expression of PaAD in E. coli was overcome when the enzyme was expressed in a fusion state (S-PaAD) and culture was cultivated at 18 °C. Moreover, the activity of S-PaAD increased by 1.5-fold as compared to that of PaAD. The ligand binding and enzyme activity assays against different substrates demonstrated that it was more active against 1 % glycogen and amylopectin. The analysis of the hydrolysates through HPLC demonstrated that the enzyme activity is mainly amylolytic, producing longer oligosaccharides as the major end product. The secondary structure analyses by temperature ramping in CD spectroscopy and MD simulation demonstrated the enzymes in the free, as well as fusion state, were stable at 90 °C. The soluble production, thermostability and broad substrate specificity make this enzyme a promising choice for various foods, feed, textiles, detergents, pharmaceuticals, and many industrial applications.


Assuntos
Domínio Catalítico , Estabilidade Enzimática , Pyrococcus abyssi , Proteínas Recombinantes de Fusão , Solubilidade , Proteínas Recombinantes de Fusão/química , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Especificidade por Substrato , Pyrococcus abyssi/enzimologia , Amilases/química , Amilases/metabolismo , Amilases/genética , Hidrólise , Escherichia coli/genética , Temperatura , Amido/química , Amido/metabolismo
7.
J Biosci Bioeng ; 135(4): 274-281, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36828688

RESUMO

One approach to achieve efficient and economical saccharification of plant biomass would be using thermostable and multifunctional enzymes from hyperthermophiles such as Thermotoga maritima. Thus, the bifunctional constructs, Cel5A-Xyn10B and Xyn10B-Cel5A, were produced by fusing cellulase Cel5A at the N- and C-terminals of xylanase Xyn10B, respectively. The Cel5A-Xyn10B fusion construct showed cellulase activity of 1483 U µmol-1 against carboxymethyl cellulose, which was nearly the same as that of Cel5A in the free form. However, xylanase activity of this construct increased by 2-fold against beechwood xylan as compared to that of Xyn10B in free form. The synergistic effect between Cel5A and Xyn10B in the form of Cel5A-Xyn10B fusion resulted an overall increase in the release of reducing sugars. However, Xyn10B-Cel5A showed about 60% decrease in activities of both the component enzymes as compared to their activities in the free form. Both the fusion constructs were active in a wide range of pH from 4.0 to 9.0 and temperatures from 50 to 90 °C. Nearly 80% of cellulase and xylanase activities were retained in Cel5A-Xyn10B fusion after incubation at 60 °C for 1 h. Secondary structures of the component enzymes were retained in the Cel5A-Xyn10B fusion as observed by circular dichroism spectroscopy. Docking and simulation studies suggested that the enhanced xylanase activity in Cel5A-Xyn10B was due to the high binding energy, favorable orientation of the active sites, as well as relative positioning of the active site residues of Cel5A and Xyn10B in closer vicinity, which facilitated the substrate channeling.


Assuntos
Celulase , Celulases , Biomassa , Polissacarídeos , Temperatura , Xilanos/metabolismo , Celulase/metabolismo
8.
Enzyme Microb Technol ; 166: 110213, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36822057

RESUMO

TpXyl10B is a glycoside hydrolase family 10 xylanase of hyperthermophile Thermotoga petrophila RKU-1. This enzyme is of considerable importance due to its thermostability. However, in its native state, this enzyme does not possess any carbohydrate-binding module (CBM) for efficient binding to plant biomass. In this study CBM6 from Clostridium thermocellum was attached to the N- and C-termini of TpXyl10B, thereby producing the variants TpXyl10B-B6C and TpXyl10B-CB6, respectively. TpXyl10B-B6C showed 5-7 folds increased activity on Beechwood xylan and the different types of plant biomass as compared to that from the catalytic domain only. However, the activity of TpXyl10B-CB6 decreased 0.6-0.8 folds on Beechwood xylan and plant biomass compared to the catalytic domain. We explained these results through molecular modeling, which showed that binding residues of CBM6's cleft B, which were previously reported to show no contribution towards binding due to steric hindrance from a loop region, were exposed in a favorable position in TpXyl10B-B6C such that they efficiently bound the substrate. In contrast, these binding residues of CBM6 in TpXyl10B-CB6 were exposed opposite to the catalytic residues; thus, binding to the substrate resulted in decreased exposure of catalytic residues to the substrate. CD spectroscopy and thermostability assays showed that TpXyl10B-B6C was highly thermostable, having a melting point > 90 °C, which is relatively higher than that of the other variant, TpXyl10B-CB6. In addition, this xylanase variant showed synergism with cellulases for the hydrolysis of plant biomass. Therefore, TpXyl10B-B6C, an engineered xylanase in this study, can be a valuable candidate for industrial applications.


Assuntos
Celulases , Celulases/metabolismo , Xilanos/metabolismo , Endo-1,4-beta-Xilanases/metabolismo , Domínio Catalítico , Archaea , Especificidade por Substrato
9.
Front Psychol ; 13: 888386, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35572235

RESUMO

Using social information processing theory, our study investigates the effect of responsible leadership on employee career success via work engagement. The model also examines whether self-enhancement motives moderate the aforementioned mediating linkages. In three waves, data were collected from employees in the education sector. Macro PROCESS was used to assess the hypotheses. According to the findings, responsible leadership boosts employee work engagement, which leads to career success. The results also suggest that responsible leadership has a stronger positive effect on work engagement among individuals high on self-enhancement motives. There is no evidence in the educational literature about the underlying process through which a responsible leadership impacts employee success. Our research addresses this gap by suggesting work engagement as a mediator of the effect of responsible leadership on individuals' career success at various degrees of self-enhancement motives.

10.
PLoS One ; 17(9): e0271126, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36174012

RESUMO

Non availability of effective anti-TB vaccine impedes TB control which remains a crucial global health issue. A fusion molecule based on immunogenic antigens specific to different growth phases of Mycobacterium tuberculosis can enhance T-cell responses required for developing a potent vaccine. In this study, six antigens including EspC, TB10.4, HspX, PPE57, CFP21 and Rv1352 were selected for constructing EspC-TB10.4 (bifu25), TnCFP21-Rv1352 (bifu29), HspX-EspC-TB10.4 (trifu37), HspX-TnCFP21-Rv1352 (trifu44) and HspX-EspC-TB10.4-PPE57 (tetrafu56) fusion proteins. Th1-cell epitopes of EspC, PPE57 and Rv1352 antigens were predicted for the first time using different in silico tools. The fusion molecule tetrafu56, which consisted of antigens from both the replicating and the dormant stages of Mtb, induced a release of 397 pg/mL of IFN-γ from PBMCs of the active TB patients. This response was comparable to the response obtained with cocktail of the component antigens (396 pg/mL) as well as to the total of the responses obtained separately for each of its component antigens (388 pg/mL). However, PBMCs from healthy samples in response to tetrafu56 showed IFN-γ release of only 26.0 pg/mL Thus a previous exposure of PBMCs to Mtb antigens in TB plasma samples resulted in 15-fold increase in IFN-γ response to tetrafu56 as compared to the PBMCs from the healthy controls. Hence, most of the T-cell epitopes of the individual antigens seem to be available for T-cell interactions in the form of the fusion. Further investigation in animal models should substantiate the immune efficacy of the fusion molecule. Thus, the fusion tetrafu56 seems to be a potential candidate for developing an effective multistage vaccine against TB.


Assuntos
Mycobacterium tuberculosis , Tuberculose dos Linfonodos , Animais , Epitopos de Linfócito T , Imunidade , Peptídeos
11.
Environ Sci Pollut Res Int ; 29(20): 30297-30310, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35000178

RESUMO

Emergencies and corruption go hand in hand in times of crisis. We are currently living in a pandemic phase, and corruption is even more damaging during these times of crisis that the world is experiencing with COVID-19. Vaccination is the only survival option that we have. The development of a nation will soon be measured by the criteria of who owns more vaccines. This study has four objectives. The first is to explore the most recent relevant literature. Moreover, we also investigate the unique trilogy of corruption, the environment, and the COVID-19 pandemic. The second is to identify adequate channels for distributing the COVID-19 vaccines. The vaccines should be dispersed based on the categories of age, gender, ethnicity, profession, and health conditions. Third, we explored the factors that are causing corruption in the distribution of the COVID-19 vaccines. Our findings show that unequal distribution, theft and black markets, weaponization of vaccines, logistical challenges, and substandard and falsified vaccines are the factors that potentially lead to corruption. The fourth objective is to investigate solutions for mitigating corruption. We revealed that blockchain, awareness, well-planned distribution channels, and prioritization of vulnerable groups are the steps that could effectively reduce corruption.


Assuntos
COVID-19 , Vacinas , Vacinas contra COVID-19 , Humanos , Pandemias , Vacinação
12.
Front Psychol ; 13: 840711, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36248529

RESUMO

Climate change has increasingly been recognised and associated with consumer behaviour: Practitioners are developing their strategies to reduce environmental degradation while increasing the management of sustainable consumption; it needs to better understand consumer attitudes and eco-friendly factors about the issue. Therefore, the current study focused to understand the effects of pro-environmental factors on individuals' environmental attitudes (purchase behaviour towards products with recycled packaging) through the lens of theory of planned behaviour in a cross-cultural setting. Moreover, present research focuses on the moderating role that religiosity plays in causal pathways between certain determinants (attitude, subjective norms, and perceived behavioural control) and intentions in this context. A multi-wave time-lagged research design was employed in this study, and university students from two developing countries were surveyed (N = 324, 266). The findings revealed pronounced similarities between the two examined countries. Overwhelmingly, pro-environmental factors examined (environmental values, environmental knowledge, and environmental concern) were found to be positively related to attitude formation. Further results showed that attitude and subjective norms are significant predictors of the intention to purchase products with recycled packaging. Moreover, with the exception of perceived behavioural control, religiosity moderates the relationships between all the determinants of TPB and intention to purchase recycled packaged products. Present study offers insightful implications to management of these emerging and/or similar cultural markets regarding customer value for green products. Using TPB, present study broadened and deepen extant stream of literature on consumption of recycled packaged products in two highly emerging markets; Pakistan and Malaysia.

13.
Front Psychol ; 13: 890064, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35936337

RESUMO

Utilizing the conservation of resources theory, this study investigates serial mediation of facades of conformity and depression between exploitative leadership and absenteeism. A total of 211 education sector employees using the convenient sampling technique took part in the survey with data collected in a time-lagged research design. Findings of the study reveal that facades of conformity and depression mediate the independent paths and play a serial mediating role between EL and absenteeism path. This study suggests that EL works as a workplace stressor, under which employees try to protect their valuable resources from further loss in the form of facades of conformity, in doing so, it leads to depression; thus, employees ultimately use absenteeism as an active coping strategy to cope with workplace stressors.

14.
Tuberculosis (Edinb) ; 136: 102253, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-36067572

RESUMO

Tuberculosis (TB) stays a major cause of death globally after COVID-19 and HIV. An early diagnosis to control TB effectively, needs a fast reliable diagnostic method with high sensitivity. Serodiagnosis involving polyclonal antibodies detection against an antigen of Mycobacterium tuberculosis (Mtb) in serum samples can be instrumental. In our study, Rv3874 and Rv3875 antigens were cloned, expressed, and purified individually and as a chimeric construct in Escherichia coli BL21. Enzyme-Linked Immunosorbent Assay (ELISA) based findings revealed that the Rv3874-Rv3875 chimeric construct was two-fold more sensitive (59.7%) than the individual sensitivities of Rv3874 (28.4%) and Rv3875 (24.9%) for 201 serum TB positive samples. Furthermore, the fusion construct was a little more sensitive (60.4%) for male subjects than that for females (58.8%). Lastly, our preliminary findings, molecular insights of secondary structure, and statistical and in silico analysis of each construct also advocate that CEP can be considered a better immunodiagnostic tool in addition to previously reported EC skin test.


Assuntos
COVID-19 , Mycobacterium tuberculosis , Tuberculose , Antígenos de Bactérias , Ensaio de Imunoadsorção Enzimática/métodos , Escherichia coli , Feminino , Humanos , Masculino , Mycobacterium tuberculosis/genética , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Sensibilidade e Especificidade , Testes Sorológicos , Tuberculose/diagnóstico
15.
Tuberculosis (Edinb) ; 127: 102053, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33561630

RESUMO

Tuberculosis (TB) is a global health problem, being prevalent in the developing countries. A rapid, reliable and cost effective diagnostic method would help in controlling TB in the endemic populations. Development of suitable fusion molecules detecting multiple antibodies produced against Mycobacterium tuberculosis antigens would enhance sensitivity of serodiagnostic assays. In this study, EspC, CFP7 and PPE57 antigens of M. tuberculosis were selected for constructing fusion molecules after prediction of B-cell epitopes using in silico tools. Fusion proteins EspC-CFP7, HspX-EspC-CFP7 and HspX-EspC-CFP7-PPE57 were expressed in E.coli (BL21). The serodiagnostic potential of the individual antigens and their fusions was analyzed by screening 230 plasma samples of pulmonary TB patients. The single antigens HspX, EspC, CFP7, PPE57 showed sensitivities of 30%, 31%, 22% and 35%, respectively. The fusion protein EspC-CFP7 showed sensitivity of 43%. Linking of HspX antigen to the N-terminus of EspC-CFP7 fusion molecule increased sensitivity to 58%, while joining PPE57 antigen to the C-terminus of HspX-EspC-CFP7 increased sensitivity to 69%. The fusion protein HspX-EspC-CFP7-PPE57 seems to be a promising molecule for use in the development of fusions with higher sensitivity.


Assuntos
Anticorpos Antibacterianos/sangue , Antígenos de Bactérias/imunologia , Proteínas de Bactérias/imunologia , Ensaio de Imunoadsorção Enzimática , Epitopos , Mycobacterium tuberculosis/imunologia , Testes Sorológicos , Tuberculose Pulmonar/diagnóstico , Antígenos de Bactérias/genética , Proteínas de Bactérias/genética , Biomarcadores/sangue , Estudos de Casos e Controles , Humanos , Mycobacterium tuberculosis/genética , Valor Preditivo dos Testes , Proteínas Recombinantes de Fusão/imunologia , Reprodutibilidade dos Testes , Tuberculose Pulmonar/sangue , Tuberculose Pulmonar/imunologia
16.
ACS Omega ; 6(16): 10506-10514, 2021 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-34056205

RESUMO

Ovarian cancer (OC) is the most lethal among female reproductive system malignancies. Depending upon the stage at presentation, the five year survival ratio varies from ∼92 to ∼30%. The role of biomarkers in early cancer diagnosis, including OC, is well understood. In our previous study, through an initial screening, we have analyzed eleven proteins that exhibited differential expression in OC using two-dimensional gel electrophoresis (2D-GE) and matrix-assisted laser desorption/ionization-time of flight mass spectrometric (MALDI-TOF MS) analysis. In continuation of our previous study, the present work describes analysis of twenty more proteins that showed aberrant expression in OC. Among these, six showed consistent significant deregulation in the OC false discovery rate [FDR ≤ 0.05]. Upon MS analysis, they were identified as vimentin, tubulin beta 2C chain, tubulin alpha 1C chain, actin cytoplasmic 2, apolipoprotein A-I, and collagen alpha 2(VI) chain [peptide mass fingerprint (PMF) score ≥ 79]. One of the differentially regulated proteins, tubulin beta 2C chain, was found to be significantly (fold change, 2.5) enhanced in OC. Verification by western blot and enzyme-linked immunosorbent assay (ELISA) demonstrated that the tubulin beta 2C chain may serve as a valuable marker for OC (ANOVA p < 0.0001). The assessment of the likely association of TBB2C with OC in a larger population will not only help in developing clinically useful biomarkers in the future but also improve our understanding of the progression of OC disease.

17.
PLoS One ; 16(11): e0258389, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34767571

RESUMO

Serodiagnosis of tuberculosis (TB) can be rapid, reliable and cost-effective if the issue of variable antibody responses of TB patients against different Mycobacterium tuberculosis (Mtb) antigens can be overcome by developing fusion proteins containing epitopes from multiple antigens of Mtb. In this study, Mtb antigens Rv1793, Rv2628, Rv2608 and a truncated variant produced by removing non-epitopic region from N-terminal of Rv2608 (tnRv2608), and the fusion protein Rv1793-Rv2628-tnRv2608 (TriFu64), were expressed in E. coli and purified. Plasma samples from TB patients characterized by sex, age and sputum/culture positivity, were used to compare the sensitivity of the single antigens with the fusion protein. Sensitivity of Rv1793, Rv2628 and Rv2608, was 27.8%, 39% and 36.3%, respectively. Truncation of Rv2608 increased sensitivity by approximately 35% in confirmed TB cases. Sensitivity of the fusion construct, TriFu64 increased to 66% with a specificity of 100%. Importantly, tnRv2608 was better able to detect sputum and culture negative patients, and this carried through to the fusion protein. We demonstrate that fusion of Mtb proteins ensures broad sensitivity across disease types, sex and age groups in a Pakistani population.


Assuntos
Antígenos de Bactérias/imunologia , Proteínas de Bactérias/imunologia , Mycobacterium tuberculosis/imunologia , Proteínas Recombinantes de Fusão/imunologia , Testes Sorológicos/métodos , Tuberculose Pulmonar/diagnóstico , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticorpos Antibacterianos/sangue , Proteínas de Bactérias/genética , Epitopos/imunologia , Escherichia coli/genética , Escherichia coli/metabolismo , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Mycobacterium tuberculosis/isolamento & purificação , Paquistão/epidemiologia , Sensibilidade e Especificidade , Escarro/microbiologia , Tuberculose Pulmonar/sangue , Tuberculose Pulmonar/epidemiologia , Tuberculose Pulmonar/microbiologia , Adulto Jovem
18.
PLoS One ; 16(1): e0245534, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33481833

RESUMO

Tuberculosis (TB) is the largest infectious disease with 10 million new active-TB patients and1.7 million deaths per year. Active-TB is an inflammatory disease and is increasingly viewed as an imbalance of immune responses to M. tb. infection. The mechanisms of a switch from latent infection to active disease is not well worked out but a shift in the immune responses is thought to be responsible. Increasingly, the role of gut microbiota has been described as a major influencer of the immune system. And because the gut is the largest immune organ, we aimed to analyze the gut microbiome in active-TB patients in a TB-endemic country, Pakistan. The study revealed that Ruminococcacea, Enetrobactericeae, Erysipelotrichaceae, Bifidobacterium, etc. were the major genera associated with active-TB, also associated with chronic inflammatory disease. Plasma antibody profiles against several M. tb. antigens, as specific biomarkers for active-TB, correlated closely with the patient gut microbial profiles. Besides, bcoA gene copy number, indicative of the level of butyrate production by the gut microbiome was five-fold lower in TB patients compared to healthy individuals. These findings suggest that gut health in TB patients is compromised, with implications for disease morbidity (e.g., severe weight loss) as well as immune impairment.


Assuntos
Disbiose/complicações , Doenças Endêmicas , Microbioma Gastrointestinal , Tuberculose/sangue , Tuberculose/microbiologia , Acil Coenzima A/genética , Adulto , Biomarcadores/sangue , Feminino , Dosagem de Genes , Humanos , Masculino , Tuberculose/complicações , Tuberculose/epidemiologia
19.
Proteomics Clin Appl ; 14(2): e1900078, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31747122

RESUMO

PURPOSE: An early and accurate diagnosis of ovarian carcinoma (OC) may reduce morbidity and mortality of the patients. To improve the clinical outcome in OC patients, the present study is aimed at identifying robust biomarkers for early OC diagnosis. EXPERIMENTAL DESIGN: In order to look for early-stage protein markers, a systematic protein profiling approach involving 2-dimensional electrophoresis coupled with mass spectrometric analyses of human malignant and non-malignant ovarian biopsy samples, is performed. RESULTS: Six 2D gel spots, corresponding to five proteins, display statistically significant differential expression in the tumor tissues compared to benign controls (FDR ≤ 0.05; PMF score ≥ 79). Ingenuity pathway analysis predicts two proteins, that is, Ca2+ -dependent membrane-binding protein annexin A6 (AnxA6) and the metabolic enzyme l-lactate dehydrogenase A chain, as potential predictive biomarkers. Increased expression of AnxA6 is further ascertained by Western blot and enzyme linked immunosorbent assay in the resected tissues and the plasma samples. The expression is found markedly increasing particularly in the advanced stage tumors. CONCLUSIONS AND CLINICAL RELEVANCE: The significant upregulation of AnxA6 in OC, reported for the first time, is likely to provide insight into the mechanism of OC progression, which may lead to the design of potential diagnostic and therapeutic strategies.


Assuntos
Anexina A6/metabolismo , Biomarcadores Tumorais/metabolismo , Cálcio/metabolismo , Neoplasias Ovarianas/metabolismo , Regulação para Cima , Adulto , Feminino , Humanos , Pessoa de Meia-Idade , Neoplasias Ovarianas/patologia
20.
Tuberculosis (Edinb) ; 124: 101981, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32810724

RESUMO

Tuberculosis (TB) is amongst the deadliest diseases worldwide. For effective control of TB a rapid, reliable and sensitive method for its diagnosis is essential. Serodiagnosis detecting multiple antibodies against antigens of Mycobacterium tuberculosis (Mtb) in blood samples could prove beneficial. Based on the epitope position in the molecule, two truncated variants of Rv1984c, i.e., Tn1Rv1984c and Tn2Rv1984c were expressed in Escherichia coli. Screening of the Rv1984c, Tn1Rv1984c and Tn2Rv1984c against 231 sera samples from the culture positive TB patients showed sensitivities of 34.2%, 49.4% and 26.8%, respectively. Another antigen Rv1352 was analyzed for the location of epitopes, which had not been reported before. A fusion molecule consisting of Tn1Rv1984c and Rv1352, expressed in E. coli, showed enhanced sensitivity of 62.8%. Joining another antigen Rv2031c to the N-terminus of Tn1Rv1984c-Rv1352, improved sensitivity to 71.4%. The fusion construct Rv2031c-Tn1Rv1984c-Rv1352 showed comparatively higher sensitivity of 73.4% in the male group as compared to 67% in the female group. Data derived for the secondary structure analysis through Circular Dichroism (CD) spectroscopy and prediction on the basis of molecular modelling was also in agreement. This construct can be a potential base for producing constructs with greater sensitivity through fusion of epitopes from additional Mtb antigens.


Assuntos
Anticorpos Antibacterianos/sangue , Antígenos de Bactérias/imunologia , Proteínas de Bactérias/imunologia , Mycobacterium tuberculosis/imunologia , Tuberculose/diagnóstico , Biomarcadores/sangue , Epitopos , Feminino , Interações Hospedeiro-Patógeno , Humanos , Masculino , Modelos Moleculares , Valor Preditivo dos Testes , Proteínas Recombinantes de Fusão/imunologia , Reprodutibilidade dos Testes , Testes Sorológicos , Tuberculose/sangue , Tuberculose/imunologia
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