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BACKGROUND: Adverse events following immunization (AEFIs), especially if serious, may impact vaccine recipients' quality of life and financial well-being and fuel vaccine hesitancy. Nigeria rolled out COVID-19 vaccination in 2021 with little known about the impact of AEFIs on an individual's quality of life. No study in Africa has explored the health and financial impact of AEFIs. We explored patient-reported outcomes (PROs) of adverse events after COVID-19 vaccination and documented the lived experiences of those with serious AEFIs to understand the effect on their health, financial well-being, and attitude to future vaccinations. METHODS: We conducted a convergent mixed-methods study using the RAND 36-item health survey and in-depth interviews to collect PROs on vaccine recipients in Nigeria. Eight health scale scores and two summary composite scores were used to measure the health-related quality of life outcomes from the survey and inductive analysis was used to identify themes from the interview scripts. The results of both studies were integrated in a joint display to highlight areas of concordance. RESULTS: In total, 785 survey responses were analyzed (53% females, 68% aged 18-30 years). Responders reporting an AEFI were 58%, of whom 62% received the first dose only. Younger age and first vaccine dose (p < .001 respectively) were associated with experiencing an AEFI. Not reporting an AEFI was associated with better quality of life, measured as higher scores on all eight SF-36 Health scales and the physical and mental component summary scores. All six interviewees with serious AEFIs experienced physical, mental, and financial distress. Some expressed a strong negative attitude toward future COVID-19 vaccinations but not toward vaccines for routine immunization. CONCLUSION: AEFIs negatively impact the health and financial well-being of affected individuals and their attitude to future vaccinations, especially if serious. Understanding the impact of AEFIs on people is important and should inform future policies and interventions. The results of our study can inform policy and planning for future mass vaccination campaigns in LMICs.
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Vacinas contra COVID-19 , COVID-19 , Medidas de Resultados Relatados pelo Paciente , Qualidade de Vida , Vacinação , Humanos , Feminino , Masculino , Nigéria , Adulto , Vacinas contra COVID-19/efeitos adversos , Vacinas contra COVID-19/administração & dosagem , Adolescente , Adulto Jovem , COVID-19/prevenção & controle , Pessoa de Meia-Idade , Vacinação/efeitos adversos , Vacinação/psicologia , SARS-CoV-2/imunologia , Inquéritos e Questionários , Idoso , Hesitação Vacinal/psicologia , Hesitação Vacinal/estatística & dados numéricosRESUMO
Mini protein mimicking uricase (mp20) has shown significant potential as a replacement for natural enzymes in the development of uric acid biosensors. However, the design of mp20 has resulted to an inactive form of peptide, causing of loss their catalytic activity. Herein, this paper delineates the impact of various metal cofactors on the catalytic activity of mp20. The metal ion-binding site prediction and docking (MIB) web server was employed to identify the metal ion binding sites and their affinities towards mp20 residues. Among the tested metal ions, Cu2+ displayed the highest docking score, indicating its preference for interaction with Thr16 and Asp17 residues of mp20. To assess the catalytic activity of mp20 in the presence of metal ions, uric acid assays was monitored using a colorimetric method. The presence of Cu2+ in the assays promotes the activation of mp20, resulting in a color change based on quinoid production. Furthermore, the encapsulation of the mp20 within zeolitic imidazolate framework-8 (ZIF-8) notably improved the stability of the biomolecule. In comparison to the naked mp20, the encapsulated ZIFs biocomposite (mp20@ZIF-8) demonstrates superior stability, selectivity and sensitivity. ZIF's porous shells provides excellent protection, broad detection (3-100⯵M) with a low limit (4.4⯵M), and optimal function across pH (3.4-11.4) and temperature (20-100°C) ranges. Cost-effective and stable mp20@ZIF-8 surpasses native uricase, marking a significant biosensor technology breakthrough. This integration of metal cofactor optimization and robust encapsulation sets new standards for biosensing applications.
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Técnicas Biossensoriais , Cobre , Simulação de Acoplamento Molecular , Urato Oxidase , Ácido Úrico , Urato Oxidase/química , Urato Oxidase/metabolismo , Ácido Úrico/metabolismo , Cobre/química , Cobre/metabolismo , Estruturas Metalorgânicas/química , Sítios de Ligação , Zeolitas/química , Estabilidade Enzimática , Imidazóis/química , Colorimetria/métodosRESUMO
The flexibility and the low production costs offered by plastics have made them crucial to society. Unfortunately, due to their resistance to biological degradation, plastics remain in the environment for an extended period of time, posing a growing risk to life on earth. Synthetic treatments of plastic waste damage the environment and may cause damage to human health. Bacterial and fungal isolates have been reported to degrade plastic polymers in a logistic safe approach with the help of their microbial cell enzymes. Recently, the bacterial strain Ideonella sakaiensis (201-F6) was discovered to break down and assimilate polyethylene terephthalate (PET) plastic via metabolic processes at 30 °C to 37 °C. PETase and MHETase enzymes help the bacterium to accomplish such tremendous action at lower temperatures than previously discovered enzymes. In addition to functioning at low temperatures, the noble bacterium's enzymes have amazing qualities over pH and PET plastic degradation, including a shorter period of degradation. It has been proven that using the enzyme PETase, this bacterium hydrolyzes the ester linkages of PET plastic, resulting in production of terephthalic acid (TPA), nontoxic compound and mono-2-hydroxyethyl (MHET), along with further depolymerization of MHET to release ethylene glycogen (EG) and terephthalic acid (TPA) by the second enzyme MHETase. Enzymatic plastic degradation has been proposed as an environmentally friendly and long-term solution to plastic waste in the environment. As a result, this review focuses on the enzymes involved in hydrolyzing PET plastic polymers, as well as some of the other microorganisms involved in plastic degradation.
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This study aims to investigate the influence of copper(II) ions as a cofactor on the electrochemical performance of a biocomposite consisting of a mini protein mimicking uricase (mp20) and zeolitic immidazolate framework-8 (ZIF-8) for the detection of uric acid. A central composite design (CCD) was utilized to optimize the independent investigation, including pH, deposition potential, and deposition time, while the current response resulting from the electrocatalytic oxidation of uric acid was used as the response. The statistical analysis of variance (ANOVA) showed a good correlation between the experimental and predicted data, with a residual standard error percentage (RSE%) of less than 2% for predicting optimal conditions. The synergistic effect of the nanoporous ZIF-8 host, Cu(II)-activated mp20, and reduced graphene oxide (rGO) layer resulted in a highly sensitive biosensor with a limit of detection (LOD) of 0.21 µM and a reproducibility of the response (RSD = 0.63%). The Cu(II)-activated mp20@ZIF-8/rGO/SPCE was highly selective in the presence of common interferents, and the fabricated layer exhibited remarkable stability with signal changes below 4.15% after 60 days. The biosensor's reliable performance was confirmed through real sample analyses of human serum and urine, with comparable recovery values to conventional HPLC.
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Cobre , Urato Oxidase , Humanos , Ácido Úrico/análise , Reprodutibilidade dos Testes , Técnicas Eletroquímicas/métodosRESUMO
Cisplatin-induced nephrotoxicity has been widely reported in numerous studies. The objective of this study is to assess the potential nephroprotective effects of Clinacanthus nutans (Burm. f.) Lindau (Acanthaceae) leaf extracts on human kidney cells (PCS-400-010) in vitro using an LCMS-based metabolomics approach. Orthogonal partial least square-discriminant analysis identified 16 significantly altered metabolites when comparing the control and pre-treated C. nutans cisplatin-induced groups. These metabolites were found to be associated with glycerophospholipid, purine, and amino acid metabolism, as well as the glycolysis pathway. Pre-treatment with C. nutans aqueous extract (125 µg/mL) for 24 h, followed by 48 h of cisplatin induction in PCS-400-010 cells, demonstrated a nephroprotective effect, particularly involving the regulation of amino acid metabolism.
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Acanthaceae , Cisplatino , Humanos , Cisplatino/efeitos adversos , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Rim , Acanthaceae/química , AminoácidosRESUMO
BLEG-1 from Bacillus lehensis G1 is an evolutionary divergent B3 metallo-ß-lactamase (MBL) that exhibited both ß-lactamase and glyoxalase II (GLXII) activities. Sequence, phylogeny, biochemical and structural relatedness of BLEG-1 to B3 MBL and GLXII suggested BLEG-1 might be an intermediate in the evolutionary path of B3 MBL from GLXII. The unique active site cavity of BLEG-1 that recognizes both ß-lactam antibiotics and S-D-lactoylglutathione (SLG) had been postulated as the key factor for its dual activity. In this study, dynamic ensembles of BLEG-1 and its substrate complexes divulged conformational plasticity and binding modes of structurally distinct substrates to the enzyme, providing better insights into its structure-to-function relationship and enzymatic promiscuity. Our results highlight the flexible nature of the active site pocket of BLEG-1, which is governed by concerted loop motions involving loop7+α3+loop8 and loop12 around the catalytic core, thereby moulding the binding pocket and facilitate interactions of BLEG-1 with both ampicillin and SLG. The distribution of (i) predominantly hydrophobic amino acids in the N-terminal domain, and (ii) flexible amino acids with polar and/or charged side chains in both N- and C-termini provide additional advantages to BLEG-1 in confining the aromatic group of ampicillin, and polar groups of SLG, respectively. The importance of these residues for substrates binding was further confirmed by the reduction in MBL and GLXII activities upon alanine substitutions of Ile-10, Phe-57, Arg-94, Leu-95, and Arg-159. Based on molecular dynamics simulation, mutational, and biochemical data presented herein, the catalytic mechanisms of BLEG-1 toward the hydrolysis of ß-lactams and SLG were proposed.
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Alanina , Antifibrinolíticos , Aminoácidos , AmpicilinaRESUMO
BACKGROUND: The frequency of antenatal care (ANC) contacts for low-risk pregnancies has been a subject of debate. OBJECTIVE: To determine the effect of frequency of ANC contacts on pregnancy outcomes amongst low-risk pregnancies and the reasons for the low antenatal visits at the Federal Teaching Hospital, Gombe, Nigeria. METHODOLOGY: This was a cross-sectional study of 510 low-risk pregnant women. They were divided into two groups; group I consisted of 255 women that had eight or more ANC contacts with at least five contacts in 3rd trimester, and group II consisted of 255 women that had seven or fewer ANC visits. Socio-demographic characteristics, haemoglobin levels at delivery, mode of delivery, maternal satisfaction, and birth outcomes were compared between the two groups. Reasons for the low antenatal visits were also documented. RESULTS: The prevalence of anemia was higher in group II compared to group I {29.4% versus 18.8% with OR 1.80 (95% CI 1.19-2.72)} while caesarean section rate was higher in group I compared to group II {16.9% versus 9.4% with OR=1.96 (95% CI: 1.11-3.48)}. There was no statistically significant difference in the fetal outcome between the two groups. Women with eight or more ANC contact were more satisfied with the ANC than those with fewer visits (OR=2.20, 95%CI 1.52-6.24). Late booking and facility-based lapses were mainly responsible for the fewer contacts. CONCLUSION: Having eight or more ANC contacts is associated with decreased maternal anaemia, better maternal satisfaction, and increased risk of caesarean delivery compared to women that have fewer ANC contacts.
CONTEXTE: La fréquence des contacts de soins prénatals (CPN) pour les grossesses à faible risque a fait l'objet d'un débat. OBJECTIF: Déterminer l'effet de la fréquence des contacts de soins prénatals sur les résultats de la grossesse parmi les grossesses à faible risque et les raisons pour lesquelles les visites prénatales sont peu nombreuses au Federal Teaching Hospital, Gombe, Nigéria. MÉTHODOLOGIE: Il s'agit d'une étude transversale portant sur 510 femmes enceintes à faible risque. Elles ont été divisées en deux groupes : le groupe I comprenait 255 femmes ayant eu huit contacts ANC ou plus, dont au moins cinq au cours du troisième trimestre, et le groupe II comprenait 255 femmes ayant eu sept visites ANC ou moins. Les caractéristiques sociodémographiques, les taux d'hémoglobine à l'accouchement, le mode d'accouchement, la satisfaction maternelle et les résultats de l'accouchement ont été comparés entre les deux groupes. Les raisons des faibles visites prénatales ont également été documentées. RÉSULTATS: La prévalence de l'anémie était plus élevée dans le groupe II que dans le groupe I {29,4 % contre 18,8 % avec un OR de 1,80 (IC à 95 % : 1,19-2,72)}, tandis que le taux de césarienne était plus élevé dans le groupe I que dans le groupe II {16,9 % contre 9,4 % avec un OR de 1,96 (IC à 95 % : 1,11-3,48)}. Il n'y a pas eu de différence statistiquement significative entre les deux groupes en ce qui concerne l'issue fÅtale. Les femmes ayant eu huit contacts ou plus avec la CPN étaient plus satisfaites de la CPN que celles ayant eu moins de visites (OR=2,20, 95%CI 1,52-6,24). La prise de rendezvous tardive et les défaillances au niveau de l'établissement étaient principalement responsables du nombre inférieur de contacts. CONCLUSION: Le fait d'avoir huit contacts CPN ou plus est associé à une diminution de l'anémie maternelle, à une meilleure satisfaction maternelle et à un risque accru d'accouchement par césarienne par rapport aux femmes qui ont moins de contacts CPN. Mots-clés: Anémie, Anténatal, Résultat de l'accouchement, Contacts, Effet, Fréquence, Satisfaction maternelle.
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Cesárea , Cuidado Pré-Natal , Gravidez , Feminino , Humanos , Nigéria , Estudos Transversais , Resultado da Gravidez , Hospitais de Ensino , Aceitação pelo Paciente de Cuidados de SaúdeRESUMO
Five mini proteins mimicking uricase comprising 20, 40, 60, 80, and 100 amino acids were designed based on the conserved active site residues within the same dimer, using the crystal structure of tetrameric uricase from Arthrobacter globiformis (PDB ID: 2yzb) as a template. Based on molecular docking analysis, the smallest mini protein, mp20, shared similar residues to that of native uricase that formed hydrogen bonds with uric acid and was chosen for further studies. Although purified recombinant mp20 did not exhibit uricase activity, it showed specific binding towards uric acid and evinced excellent thermotolerance and structural stability at temperatures ranging from 10°C to 100°C, emulating its natural origin. To explore the potential of mp20 as a bioreceptor in uric acid sensing, mp20 was encapsulated within zeolitic imidazolate framework-8 (mp20@ZIF-8) followed by the modification on rGO-screen printed electrode (rGO/SPCE) to maintain the structural stability. An irreversible anodic peak and increased semicircular arcs of the Nyquist plot with an increase of the analyte concentrations were observed by utilizing cyclic voltammetry and electrochemical impedance spectroscopy (EIS), suggesting the detection of uric acid occurred, which is based on substrate-mp20 interaction.
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Grafite , Ácido Úrico , Ácido Úrico/análise , Ácido Úrico/química , Urato Oxidase/genética , Urato Oxidase/química , Urato Oxidase/metabolismo , Simulação de Acoplamento MolecularRESUMO
Heterologous functional expression of the recombinant lipases is typically a bottleneck due to the expression in the insoluble fraction as inclusion bodies (IBs) which are in inactive form. Due to the importance of lipases in various industrial applications, many investigations have been conducted to discover suitable approaches to obtain functional lipase or increase the expressed yield in the soluble fraction. The utilization of the appropriate prokaryotic and eukaryotic expression systems, along with the suitable vectors, promoters, and tags, has been recognized as a practical approach. One of the most powerful strategies to produce bioactive lipases is using the molecular chaperones co-expressed along with the target protein's genes into the expression host to produce the lipase in soluble fraction as a bioactive form. The refolding of expressed lipase from IBs (inactive) is another practical strategy which is usually carried out through chemical and physical methods. Based on recent investigations, the current review simultaneously highlights strategies to express the bioactive lipases and recover the bioactive lipases from the IBs in insoluble form.
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Lipase , Chaperonas Moleculares , Lipase/química , Chaperonas Moleculares/genética , Escherichia coli/genética , Proteínas Recombinantes/químicaRESUMO
Lipase biocatalysts offer unique properties which are often impaired by low thermal and methanol stability. In this study, the rational design was employed to engineer a disulfide bond in the protein structure of Geobacillus zalihae T1 lipase in order to improve its stability. The selection of targeted disulfide bond sites was based on analysis of protein spatial configuration and change of Gibbs free energy. Two mutation points (S2C and A384C) were generated to rigidify the N-terminal and C-terminal regions of T1 lipase. The results showed the mutant 2DC lipase improved methanol stability from 35 to 40% (v/v) after 30 min of pre-incubation. Enhancement in thermostability for the mutant 2DC lipase at 70 °C and 75 °C showed higher half-life at 70 °C and 75 °C for 30 min and 52 min, respectively. The mutant 2DC lipase maintained the same optimum temperature (70 °C) as T1 lipase, while thermally induced unfolding showed the mutant maintained higher rigidity. The kcat/Km values demonstrated a relatively small difference between the T1 lipase (WT) and 2DC lipase (mutant). The kcat/Km (s-1 mM-1) of the T1 and 2DC showed values of 13,043 ± 224 and 13,047 ± 312, respectively. X-ray diffraction of 2DC lipase crystal structure with a resolution of 2.04 Å revealed that the introduced single disulfide bond did not lower initial structural interactions within the residues. Enhanced methanol and thermal stability are suggested to be strongly related to the newly disulfide bridge formation and the enhanced compactness and rigidity of the mutant structure. KEY POINTS: ⢠Protein engineering via rational design revealed relative improved enzymatic performance. ⢠The presence of disulfide bond impacts on the rigidity and structural function of proteins. ⢠X-ray crystallography reveals structural changes accompanying protein modification.
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Lipase , Metanol , Metanol/metabolismo , Lipase/metabolismo , Estabilidade Enzimática , Temperatura , Dissulfetos/químicaRESUMO
Engineered thermostable microbial enzymes are widely employed to catalyze chemical reactions in numerous industrial sectors. Although high thermostability is a prerequisite of industrial applications, enzyme activity is usually sacrificed during thermostability improvement. Therefore, it is vital to select the common and compatible strategies between thermostability and activity improvement to reduce mutantsÌ libraries and screening time. Three functional protein engineering approaches, including directed evolution, rational design, and semi-rational design, are employed to manipulate protein structure on a genetic basis. From a structural standpoint, integrative strategies such as increasing substrate affinity; introducing electrostatic interaction; removing steric hindrance; increasing flexibility of the active site; N- and C-terminal engineering; and increasing intramolecular and intermolecular hydrophobic interactions are well-known to improve simultaneous activity and thermostability. The current review aims to analyze relevant strategies to improve thermostability and activity simultaneously to circumvent the thermostability and activity trade-off of industrial enzymes.
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Engenharia de Proteínas , Estabilidade Enzimática , TemperaturaRESUMO
Plastic or microplastic pollution is a global threat affecting ecosystems, with the current generation reaching as much as 400 metric tons per/year. Soil ecosystems comprising agricultural lands act as microplastics sinks, though the impact could be unexpectedly more far-reaching. This is troubling as most plastic forms, such as polyethylene terephthalate (PET), formed from polymerized terephthalic acid (TPA) and ethylene glycol (EG) monomers, are non-biodegradable environmental pollutants. The current approach to use mechanical, thermal, and chemical-based treatments to reduce PET waste remains cost-prohibitive and could potentially produce toxic secondary pollutants. Thus, better remediation methods must be developed to deal with plastic pollutants in marine and terrestrial environments. Enzymatic treatments could be a plausible avenue to overcome plastic pollutants, given the near-ambient conditions under which enzymes function without the need for chemicals. The discovery of several PET hydrolases, along with further modification of the enzymes, has considerably aided efforts to improve their ability to degrade the ester bond of PET. Hence, this review emphasizes PET-degrading microbial hydrolases and their contribution to alleviating environmental microplastics. Information on the molecular and degradation mechanisms of PET is also highlighted in this review, which might be useful in the future rational engineering of PET-hydrolyzing enzymes.
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Poluentes Ambientais , Polietilenotereftalatos , Polietilenotereftalatos/química , Plásticos/química , Hidrolases/metabolismo , Microplásticos , Ecossistema , Biodegradação Ambiental , Solo , Ésteres , EtilenoglicóisRESUMO
Background: Diarrhoea is a major cause of childhood morbidity and mortality in developing countries including Nigeria. Rotavirus is a leading cause of acute watery diarrhoea in children under 5 years of age. Aims: The aim of the study is to determine the prevalence of rotavirus diarrhoea in children less than 5 years old presenting with watery diarrhoea at the University of Maiduguri Teaching Hospital. The cross-sectional study was carried out at University of Maiduguri Teaching Hospital (UMTH), a referral tertiary centre for northeast Nigeria and neighbouring Cameroon, Chad, and Niger Republic. Study population were children under five presenting to UMTH with acute diarrhoea. Freshly passed stool was collected from each participant in a universal sterile container and transported to the department of medical microbiology laboratory UMTH, Rotavirus antigen was detected using Rota - dipstick an immunochromatographic test. The positive samples were subjected to RT-PCR to detect the VP 7 gene of the dsRNA. Patients and Methods: SPSS Version 25. Results: The prevalence was found to be 14.5% in the population studied and was highest among children below 1 year of age. Conclusions: This study has confirmed that rotavirus is an important cause of childhood diarrhoea. The burden of childhood diarrhoea can be reduced by introduction of vaccines, and children of 1 year old and younger will benefit from this vaccine as most study participants have not been vaccinated. Creating awareness on prevention and control of this infection with mass vaccination will go a long way in reducing the prevalence and mortality rate of rotavirus diarrhoea.
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Infecções por Rotavirus , Rotavirus , Criança , Pré-Escolar , Estudos Transversais , Diarreia/epidemiologia , Hospitais de Ensino , Humanos , Lactente , Nigéria/epidemiologia , Prevalência , Rotavirus/genética , Infecções por Rotavirus/epidemiologia , Infecções por Rotavirus/prevenção & controle , UniversidadesRESUMO
Thermostability is an essential requirement of enzymes in the industrial processes to catalyze the reactions at high temperatures; thus, enzyme engineering through directed evolution, semi-rational design and rational design are commonly employed to construct desired thermostable mutants. Several strategies are implemented to fulfill enzymes' thermostability demand including decreasing the entropy of the unfolded state through substitutions Gly â Xxx or Xxx â Pro, hydrogen bond, salt bridge, introducing two different simultaneous interactions through single mutant, hydrophobic interaction, filling the hydrophobic cavity core, decreasing surface hydrophobicity, truncating loop, aromatic-aromatic interaction and introducing positively charged residues to enzyme surface. In the current review, horizons about compatibility between secondary structures and substitutions at preferable structural positions to generate the most desirable thermostability in industrial enzymes are broadened. KEY POINTS: ⢠Protein engineering is a powerful tool for generating thermostable industrial enzymes. ⢠Directed evolution and rational design are practical approaches in enzyme engineering. ⢠Substitutions in preferable structural positions can increase thermostability.
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Engenharia de Proteínas , Estabilidade Enzimática , Ligação de Hidrogênio , Estrutura Secundária de Proteína , TemperaturaRESUMO
This work presents the use of encapsulated mini protein 20 mimicking uricase (mp20)-zeolitic imidazolate framework-8 (ZIF-8) as a bioreceptor for the development of a nanozyme-based electrochemical biosensor for uric acid detection. The electrochemical performance of the biofunctionalized mp20@ZIF-8 on the reduced graphene oxide/screen-printed carbon electrode (rGO/SPCE) was investigated by optimizing operating parameters such as pH, deposition potential, and deposition time using a central composite design-response surface methodology (CCD-RSM). The quadratic regression model was developed to correlate the combination of each variable to the oxidation current density as a response. A significant effect on current response was observed under optimized conditions of pH of 7.4 at −0.35 V deposition potential and 56.56 s deposition time, with p < 0.05 for each interacted factor. The obtained coefficient of determination (R2) value of 0.9992 indicated good agreement with the experimental finding. The developed nanozyme biosensor (mp20@ZIF-8/rGO/SPCE) exhibited high selectivity in the presence of the same fold concentration of interfering species with a detection limit of 0.27 µM, over a concentration range of 1 to 34 µM. The practicality of the tailored biosensor in monitoring uric acid in human serum and urine samples was validated with high-performance liquid chromatography (HPLC) and a commercial uric acid meter. Hence, nanozyme-based is a promising platform that offers a rapid, sensitive, selective, and low-cost biosensor for the non-enzymatic detection of uric acid in biological samples.
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Metallo-ß-lactamases (MBLs) are class B ß-lactamases from the metallo-hydrolase-like MBL-fold superfamily which act on a broad range of ß-lactam antibiotics, thus conferring antibiotics resistance to bacterial pathogens. The attempt to structurally characterize BLEG-1, an evolutionary divergent B3 metallo-ß-lactamase (MBL) with dual activity from Bacillus lehensis G1, led to the optimization of its purification, post-purification and crystallization processes for X-ray diffraction purpose. The workflow, conditions used and dataset obtained from each stage of the processes are presented herein. The optimization workflow has enabled the obtainment of purified, active BLEG-1 in high yield for its activity assays, crystallization and structure determination via X-ray diffraction. This is the first step to gain a better insight into its dual activity and evolutionary divergence from a structural perspective. The complete research article, including BLEG-1 dual activity analysis, is published in the International Journal of Molecular Sciences (Au et al., 2021). ⢠The method was optimized to increase the stability of BLEG-1 in purification, post-purification and crystallization processes. ⢠Protein crystallization using the optimized conditions presented herein is able to produce and regenerate BLEG-1 protein crystals of medium-size, which is an advantage in X-ray diffraction. ⢠The method can be used for relevant homologs and variants of BLEG-1 for structure-function and mechanistic studies of such proteins.
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Keratinase is an important enzyme that is used to degrade feather wastes produced by poultry industries and slaughterhouses that accumulate rapidly over time. The search for keratinase-producing microorganisms is important to potentially substitute physicochemical treatments of feather waste. In this study, the genome of Bacillus cereus HD1 and its keratinolytic prowess was investigated. The whole-genome shotgun size is 5,668,864 bp consisting of 6083 genes, 69 tRNAs, and 10 rRNAs. The genomic analyses revealed 15 potential keratinase genes and other enzymes that might assist keratin degradation, such as disulfide reductase and cysteine dioxygenase. The optimal conditions for feather degradation and keratinase production by B. cereus HD1 such as incubation time, pH, temperature, yeast extract, and glycerol concentrations were determined to be 5 days, pH 8, 37 °C, 0.05% (w/v), and 0.1% (v/v), respectively. Under optimized conditions, B. cereus HD1 exhibited feather degradation of 65%, with bacterial growth and maximum keratinase activity of 1.3 × 1011 CFU/mL and 41 U/mL, respectively, after 5 days of incubation in a feather basal medium. The findings obtained from this study may facilitate further research into utilizing B. cereus HD1 as a prominent keratinolytic enzymes production host and warrant potential biotechnological applications.
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Bacillus cereus , Plumas , Animais , Bacillus cereus/genética , Bacillus cereus/metabolismo , Galinhas , Plumas/química , Plumas/metabolismo , Plumas/microbiologia , Concentração de Íons de Hidrogênio , Peptídeo Hidrolases/metabolismoRESUMO
Background: Hepatitis is one of the leading causes of morbidity and mortality, particularly in developing countries. It is often caused by hepatitis B and C, which are both preventable and treatable. Available information on Hepatitis B and C in Nigeria is based primarily on estimates obtained from specific population sub-groups or hospital-based surveys leaving gaps in population-level knowledge, attitudes, and prevalence. This study aimed to assess the knowledge, attitude and associated factors of hepatitis B virus (HBV) and hepatitis C virus (HCV) infections amongst residents of Lagos State. Methodology: This was a community-based descriptive cross-sectional study carried out in all the 20 local government areas of Lagos state using a multistage sampling technique. Data were collected using pre-tested interviewer-administered questionnaires. Blood samples were taken (pinprick) from respondents (n = 4862) and tested using hepatitis B and C surface antigen tests after obtaining informed consent. Results: The overall prevalence of HBV infection in Lagos State was 2.1% while the prevalence of HCV infection was 0.1%. Only about half of all the respondents (50.9%) had heard about hepatitis B before the survey. Knowledge of the specific symptoms of HBV was also very low. For instance, only 28.1% of the respondents knew that yellowness of the eyes is associated with hepatitis while < 1% (0.1%) knew that HBV infection is associated with the passage of yellow urine. The most common source of information about hepatitis was the radio (13.0%). Only 36.2% of the respondents knew that HBV infection could be prevented. Overall, 28.8% of the respondents were aware of the hepatitis B vaccine. Less than half (40.9%) felt it was necessary to get vaccinated against HBV, however, a similar proportion (41.9%) would want to be vaccinated against HBV. Only 2.5% of all the respondents had ever received HBV vaccines while 3.5% had ever been tested for hepatitis B before this survey. There was a statistically significant association between HBV infection and respondents' use of shared clippers and work exposure involving contact with body parts and body fluids (P < 0.05). Conclusion: The knowledge, awareness and risk perception of HBV infection were low, however, almost half of the residents were willing to receive hepatitis B vaccinations if offered. It is recommended that the population-based prevention programmes and regular community-based surveillance be conducted by the public health department of Lagos State Ministry of Health. In addition, the strengthening of routine immunisation and vaccination of high-risk groups should be prioritised.
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Hepatite B , Hepatite C , Estudos Transversais , Conhecimentos, Atitudes e Prática em Saúde , Hepatite B/epidemiologia , Hepatite B/prevenção & controle , Vacinas contra Hepatite B , Vírus da Hepatite B , Hepatite C/epidemiologia , Hepatite C/prevenção & controle , Humanos , Nigéria/epidemiologia , Estudos SoroepidemiológicosRESUMO
Polyhydroxyalkanoates (PHA) are microbial polymers that have received widespread attention in recent decades as potential alternatives to some petrochemical-based plastics. However, widespread use of PHA is often impeded by its cost of production. Therefore, the search for and systematic investigation of versatile microbial PHA producers capable of using various carbon sources, even in the form of animal fats, for PHA biosynthesis is desirable. This study highlights the PHA production capacity, monomer composition and molecular weight synthesized by Burkholderia cepacia JC-1, a locally isolated strain from soil, from various carbon sources. In the category of simple sugars and plant oils, the use of glucose and palm oil at C:N ratio of 40 resulted in the highest accumulation of 52 wt% and 36 wt% poly(3-hydroxybutyrate) [P(3HB)] homopolymer and dry cell weight of 2.56 g/L and 3.17 g/L, respectively. Interestingly, B. cepacia JC-1 was able to directly utilize animal-derived lipid in the form of crude and extracted chicken fat, resulting in appreciable dry cell weight and PHA contents of up to 3.19 g/L and 47 wt% respectively, surpassing even that of palm oil in the group of triglycerides as substrates. The presence of antibiotics (streptomycin) in cultivation medium did not significantly affect cell growth and polymer production. The supply of sodium pentanoate as a co-substrate resulted in the incorporation of 3-hydroxyvalerate (3HV) monomer at fractions up to 37 mol%. The molecular weight of polymers produced from glucose, palm oil and chicken fat were in the range of 991-2118 kDa, higher than some reported studies involving native strains. The results from this study form an important basis for possible improvements in using B. cepacia JC-1 and crude chicken fats in solid form for PHA production in the future.