RESUMO
Lipases form one of the most important groups of biocatalysts used in biotechnology. We studied the lipase from the bacterium Cohnella sp. A01 due to the versatility of thermophilic lipases in industry. In this study lipase 3646 gene from the thermophilic bacterium Cohnella sp. A01 was expressed in Escherichia coli and the enzyme was purified by a two-steps anion exchange chromatography. The purified lipase appeared to have a molecular weight of approximately 29.5kDa on SDS-PAGE. The values of Km and Vmax, calculated by the Michaelis-Menten equation, were 1077µM and 61.94U/mg, respectively. The kinetic characterization of the purified enzyme exhibited maximum activity at 70°C and pH 8.5. Activities at 50, 55 and 60°C for 120min were measured 58%, 47% and 41%, respectively. The enzyme was also highly stable at the pH range of 8.5-10.0 for 180min. The effect of EDTA indicated that the enzyme is not a metalloenzyme. The stability of lipase 3646 in the presence of organic solvents, detergents, metal ions and inhibitors suggested that this lipase could be exploited in certain industries such as detergent and leather. Lipase 3646 was determined structurally to be 37.5% α-helix, 12.8% ß-sheet, 22.7% ß-turn and 27% random coil.
Assuntos
Bacillus/enzimologia , Clonagem Molecular/métodos , Lipase/isolamento & purificação , Lipase/metabolismo , Temperatura , Cromatografia por Troca Iônica , Dicroísmo Circular , Detergentes/farmacologia , Inibidores Enzimáticos/farmacologia , Estabilidade Enzimática/efeitos dos fármacos , Concentração de Íons de Hidrogênio , Íons , Metais/farmacologia , Modelos Moleculares , Compostos Orgânicos/farmacologia , Proteínas Recombinantes/isolamento & purificação , Solventes/farmacologia , Especificidade por Substrato/efeitos dos fármacosRESUMO
Angiotensin-converting enzyme 2 (ACE2) has a specific interaction with the coronavirus spike protein, enabling its entry into human cells. This membrane enzyme converts angiotensin II into angiotensin 1-7, which has an essential role in protecting the heart and improving lung function. Many therapeutic properties have been attributed to the human recombinant ACE2 (hrACE2), especially in combating complications related to diabetes mellitus and hypertension, as well as, preventing the coronavirus from entering the target tissues. In the current study, we designed an appropriate gene construct for the hybrid protein containing the ACE2 catalytic subunit and the B subunit of cholera toxin (CTB-ACE2). This structural feature will probably help the recombinant hybrid protein enter the mucosal tissues, including the lung tissue. Optimization of this hybrid protein expression was investigated in BL21 bacterial host cells. Also, the hybrid protein was identified with an appropriate antibody using the ELISA method. A large amount of the hybrid protein (molecular weight of ~ 100 kDa) was expressed as the inclusion body when the induction was performed in the presence of 0.25 mM IPTG and 1% sucrose for 10 h. Finally, the protein structural features were assessed using several biophysical methods. The fluorescence emission intensity and oligomeric size distribution of the CTB-ACE2 suggested a temperature-dependent alteration. The ß-sheet and α-helix were also dominant in the hybrid protein structure, and this protein also displays acceptable chemical stability. In overall, according to our results, the efficient expression and successful purification of the CTB-ACE2 protein may pave the path for its therapeutic applications against diseases such as covid-19, diabetes mellitus and hypertension.
Assuntos
Diabetes Mellitus , Hipertensão , Humanos , Toxina da Cólera/genética , Toxina da Cólera/metabolismo , Enzima de Conversão de Angiotensina 2/genética , Enzima de Conversão de Angiotensina 2/metabolismo , Domínio CatalíticoRESUMO
Glioblastoma multiforme (GBM) is a highly invasive brain malignancy originating from astrocytes, accounting for approximately 30% of central nervous system malignancies. Despite advancements in therapeutic strategies including surgery, chemotherapy, and radiopharmaceutical drugs, the prognosis for GBM patients remains dismal. The aggressive nature of GBM necessitates the identification of molecular targets and the exploration of effective treatments to inhibit its proliferation. The Notch signaling pathway, which plays a critical role in cellular homeostasis, becomes deregulated in GBM, leading to increased expression of pathway target genes such as MYC, Hes1, and Hey1, thereby promoting cellular proliferation and differentiation. Recent research has highlighted the regulatory role of non-coding RNAs (ncRNAs) in modulating Notch signaling by targeting critical mRNA expression at the post-transcriptional or transcriptional levels. Specifically, various types of ncRNAs, including long non-coding RNAs (lncRNAs) and microRNAs (miRNAs), have been shown to control multiple target genes and significantly contribute to the carcinogenesis of GBM. Furthermore, these ncRNAs hold promise as prognostic and predictive markers for GBM. This review aims to summarize the latest studies investigating the regulatory effects of ncRNAs on the Notch signaling pathway in GBM.
Assuntos
Neoplasias Encefálicas , Glioblastoma , RNA não Traduzido , Receptores Notch , Transdução de Sinais , Humanos , Glioblastoma/genética , Glioblastoma/terapia , Glioblastoma/metabolismo , Receptores Notch/metabolismo , Receptores Notch/genética , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/terapia , Neoplasias Encefálicas/metabolismo , RNA não Traduzido/genética , Prognóstico , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Regulação Neoplásica da Expressão GênicaRESUMO
α-crystallin is a structurally essential small heat shock protein (sHSP) with a chaperone-like activity which maintains transparency of the lenticular tissues during a period of time that is as long as human life. α-crystallin is a multimeric protein consisting of αA and αB subunits, with 57 % homology. The CRYAB gene on chromosome 11 encodes human αB-crystallin (αB-Cry), which contains 175 amino acid residues. In the current study, the cataractogenic mutations R12C, P20R, R69C, and double mutations R12C/P20R and R12C/P20R were embedded into the human CRYAB gene. Following successful expression in the prokaryotic system and purification, a number of spectroscopic techniques, gel electrophoresis, dynamic light scattering (DLS), and transmission electron microscopy (TEM) were applied to assess the role of these mutations on the structure, amyloidogenicity, and biological function of human αB-Cry. The created mutations caused significant changes in the structure, and oligomeric state of human αB-Cry. These mutations, particularly R12C, R12C/P20R, and R12C/R69C, dramatically enhanced the tendency of this protein for the amyloid fibril formation and reduced its chaperone-like activity. Since double mutations R12C/P20R and R12C/P20R were able to intensely change the protein's structure and chaperone function, it can be suggested that they may play a destructive role in a cumulative manner. Our findings indicated that the simultaneous presence of two pathogenic mutations may have a cumulative destructive impacts on the structure and function of human αB-Cry and this observation is likely related to the disease severity of the mutated proteins.
Assuntos
Catarata , alfa-Cristalinas , Humanos , Catarata/genética , Cadeia B de alfa-Cristalina/genética , Cadeia B de alfa-Cristalina/química , Mutação , Dobramento de Proteína , alfa-Cristalinas/metabolismoRESUMO
This review explores the potential of photonic nanoparticles for cancer theranostics. Photonic nanoparticles offer unique properties and photonics capabilities that make them promising materials for cancer treatment, particularly in the presence of near-infrared light. However, the size of the particles is crucial to their absorption of near-infrared light and therapeutic potential. The limitations and challenges associated with the clinical use of photonic nanoparticles, such as toxicity, immune system clearance, and targeted delivery to the tumor are also discussed. Researchers are investigating strategies such as surface modification, biodegradable nanoparticles, and targeting strategies to improve biocompatibility and accumulation in the tumor. Ongoing research suggests that photonic nanoparticles have potential for cancer theranostics, further investigation and development are necessary for clinical use.
Tiny particles called 'photonic nanoparticles' can be used to help treat cancer. These particles have special properties that allow them to be used with special light to treat cancer. However, the size of the particles is really important, so scientists are trying to find ways to make sure they are the right size. There are also some challenges with using these particles in people, like making sure they don't harm the body and that they go to the right place. Scientists are working on ways to improve the safety of these particles and make sure they go where they need to.
Assuntos
Nanopartículas Metálicas , Nanopartículas , Neoplasias , Humanos , Medicina de Precisão , Óptica e Fotônica , Nanomedicina Teranóstica , Neoplasias/diagnóstico , Neoplasias/tratamento farmacológicoRESUMO
αB-crystallin (heat shock protein ß5/HSPB5) is a member of the family of small heat shock proteins that is expressed in various organs of the human body including eye lenses and muscles. Therefore, mutations in the gene of this protein (CRYAB) might have many pathological consequences. A new mutation has recently been discovered in the α-crystallin domain of this chaperone protein which replaces aspartate 109 with alanine (D109A). This mutation can cause myofibrillar myopathy (MFM), cataracts, and cardiomyopathy. In the current study, several spectroscopic and microscopic analyses, as well as gel electrophoresis assessment were applied to elucidate the pathogenic contribution of human αB-crystallin bearing D109A mutation in development of eye lens cataract and myopathies. The protein oligomerization, chaperone-like activity and chemical/thermal stabilities of the mutant and wild-type protein were also investigated in the comparative assessments. Our results suggested that the D109A mutation has a significant impact on the important features of human αB-crystallin, including its structure, size of the protein oligomers, tendency to form amyloid fibrils, stability, and chaperone-like activity. Given the importance of aspartate 109 in maintaining the proper structure of the α-crystallin domain, its role in the dimerization and chaperone-like activity, as well as preserving protein stability through the formation of salt bridges; mutation at this important site might have critical consequences and can explain the genesis of myopathy and cataract disorders. Also, the formation of large light-scattering aggregates and disruption of the chaperone-like activity by D109A mutation might be considered as important contributing factors in development of the eye lens opacity.
Assuntos
Cardiomiopatias/genética , Catarata/genética , Mutação Puntual , Cadeia B de alfa-Cristalina/genética , Cardiomiopatias/metabolismo , Catarata/metabolismo , Humanos , Modelos Moleculares , Conformação Proteica , Dobramento de Proteína , Multimerização Proteica , Estabilidade Proteica , Cadeia B de alfa-Cristalina/química , Cadeia B de alfa-Cristalina/metabolismoRESUMO
Lipases (triacylglycerol acylhydrolase, EC 3.1.1.3) are one of the highest value commercial enzymes as they have potential applications in biotechnology for detergents, food, pharmaceuticals, leather, textiles, cosmetics, and paper industries; and are currently receiving considerable attention because of their potential applications in biotechnology. Bacillus thermocatenulatus Lipase 2 (BTL2) is one of the most important research targets, because of its potential industrial applications. In this study, the effect of substitution Phe17 with Ser in mutated BTL2 lipase, which conserved pentapeptide (112Ala-His-Ser-Gln-Gly116) was replaced with similar sequences (207Gly-Glu-Ser-Ala-Gly211) of Candida rugosa lipase (CLR) at the nucleophilic elbow region. Docking results confirmed the mutated lipase to be better than the chimeric lipase. So, cloning was conducted, and the mutated and chimeric btl2 genes were expressed in Escherichia coli, and then the enzymes were purified by anion exchange chromatography. The mutation increased lipase lipolytic activity against most of the applied substrates, with the exception of tributyrin when compared with chimeric lipase. Further, the mutated lipase exhibited higher activity than the chimeric lipase at all temperatures. Optimum pH of the mutated lipase was obtained at pH 9.5, which was more than the chimeric one. Enzyme activity of the mutated lipase in the presence of organic solvents, detergents, and metal ions was also improved than the chimeric lipase.