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1.
J Med Virol ; 95(7): e28965, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37488710

RESUMEN

The distinct disease progression patterns of severe acute respiratory syndrome coronavirus clade 2 (SARS-CoV-2) indicate diverse host immune responses. SARS-CoV-2 severely impairs type I interferon (IFN) cell signaling, resulting in uncontrolled late-phase lung damage in patients. For better pharmacological properties, cytokine modifications may sometimes result in a loss of biological activity against the virus. Here, we employed the genetic code expansion and engineered IFN-ß, a phase II clinical cytokine with 3-amino tyrosine (IFN-ß-A) that reactivates STAT2 expression in virus-infected human cells through JAK/STAT cell signaling without affecting signal activation and serum half-life. This study identified that genetically encoded IFN-ß-A might stabilize the protein-receptor complex and trigger JAK-STAT cell signaling, which is a promising modality for controlling SARS-CoV-2 infection.


Asunto(s)
COVID-19 , SARS-CoV-2 , Humanos , Membrana Celular , Citocinas , Progresión de la Enfermedad
2.
Mol Biol Rep ; 46(1): 133-141, 2019 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-30374769

RESUMEN

Urease is a potent metalloenzyme with diverse applications. This paper describes the scale up and purification of an extracellular urease from Arthrobacter creatinolyticus MTCC 5604. The urease production was scaled-up in 3.7 L and 20 L fermentor. A maximum activity of 27 and 27.8 U/mL and a productivity of 0.90 and 0.99 U/mL/h were obtained at 30 h and 28 h in 3.7 and 20 L fermentor, respectively. Urease was purified to homogeneity with 49.85-fold purification by gel filtration and anion exchange chromatography with a yield of 36% and a specific activity of 1044.37 U/mg protein. The enzyme showed three protein bands with molecular mass of 72.6, 11.2 and 6.1 kDa on SDS-PAGE and ~ 270 kDa on native PAGE. The cytotoxic effect of urease was assessed in vitro using cancer cell lines (A549 and MG-63) and normal cell line (HEK 293). Urease showed its inhibitory effects on cancer cell lines through the generation of toxic ammonia, which in turn increased the pH of the surrounding medium. This increase in extracellular pH, enhanced the cytotoxic effect of weak base chemotherapeutic drugs, doxorubicin (50 µM) and vinblastine (100 µM) in the presence of urease (5 U/mL) and urea (0-4 mM) significantly.


Asunto(s)
Arthrobacter/enzimología , Ureasa/aislamiento & purificación , Ureasa/farmacología , Células A549/efectos de los fármacos , Amoníaco/metabolismo , Arthrobacter/metabolismo , Arthrobacter/fisiología , Línea Celular , Cromatografía en Gel/métodos , Electroforesis en Gel de Poliacrilamida/métodos , Células HEK293 , Humanos , Concentración de Iones de Hidrógeno/efectos de los fármacos , Peso Molecular , Urea/metabolismo , Ureasa/fisiología
3.
Indian J Exp Biol ; 54(1): 72-5, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26891555

RESUMEN

The production of α-galactosidase from the wild fungal strain Aspergillus foetidus MTCC 6322 using solid state fermentation (SSF), its characterization, and its efficacy in the hydrolysis of soymilk using response surface methodology were studied. The optimum conditions for production of α-galactosidase by SSF were: wheat bran (10 g), moisture content (64%), inoculum volume (1.0 mL; 6 x 10(7) spores/mL) with a yield of 4.1 x 10(3) units per gram dry substrate (U/gds) at 96 h. The enzyme showed optimum activity at 6.0, temperature 40 degrees C, pH stability between 5.0-8.0, and temperature stability between 30-40 degrees C. The enzyme was stable in the presence of trypsin, lipase, and collagenase and it showed susceptibility of the substrates such as raffinose, melibiose, guar gum and soymilk to hydrolysis in varying degrees. The optimized conditions for soymilk hydrolysis were: soymilk (10 mL) from defatted soybean meal (1.5%), α-galactosidase (0.15 UmL(-1) at 30 degrees C, pH 6.0 and duration of 1 h.


Asunto(s)
Aspergillus , Fermentación , alfa-Galactosidasa , Concentración de Iones de Hidrógeno , Hidrólisis , Temperatura
4.
Indian J Exp Biol ; 51(4): 336-42, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24195353

RESUMEN

Proteases are shown to have greener mode of application in leather processing for dehairing of goat skins and cow hides. Production of protease by submerged fermentation with potent activity is reported using a new isolate P. aeruginosa MTCC 10501. The production parameters were optimized by statistical methods such as Plackett-Burman and response surface methodology. The optimized production medium contained (g/L); tryptone, 2.5; yeast extract, 3.0; skim milk 30.0; dextrose 1.0; inoculum concentration 4%: initial pH 6.0; incubation temperature 30 degrees C and optimum production at 48 h with protease activity of 7.6 U/mL. The protease had the following characteristics: pH optima, 9.0; temperature optima 50 degrees C; pH stability between 5.0-10.0 and temperature stability between 10-40 degrees C. The protease was observed to have high potential for dehairing of goat skins in the pre- tanning process comparable to that of the chemical process as evidenced by histology. The method offers cleaner processing using enzyme only instead of toxic chemicals in the pre-tanning process of leather manufacture.


Asunto(s)
Proteínas Bacterianas/biosíntesis , Endopeptidasas/biosíntesis , Microbiología Industrial/métodos , Pseudomonas aeruginosa/metabolismo , Animales , Medios de Cultivo , Cabras , Concentración de Iones de Hidrógeno , Industrias , Modelos Estadísticos , Peptonas/química , Presión , Curtiembre , Temperatura , Levaduras/química
5.
Chemosphere ; 311(Pt 1): 136756, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36228731

RESUMEN

Lead (Pb2+) is a well-known heavy metal and toxic synthetic industrial pollutant in the ecosystem and causes severe threats to living organisms. It is paramount to develop a sustainable microbial engineering approach to remove synthetic pollutants from the environment. Genetic code engineering is emerging as an important microbial engineering tool in biosciences to biosynthesis congener protein production beyond the canonical set of natural molecules and expand the chemistries of living cells. Here, we prepare cells expressing unnatural amino acid encoded congener proteins for effectively removable toxic synthetic industrial pollutants (Pb2+) with high binding efficiency. Native and the developed congener proteins expressing cells adapted the Langmuir and Sips adsorption model that recommends uniform adsorption with Pb2+ ions. This could be due to a more significant number of functional groups on the protein surface. Fluorescence spectroscopic, field emission scanning electron microscope, X-ray photoelectron spectroscopic analysis, and protein-metal molecular stimulation coordination allowed us to explore the role of hydroxylation on Pb2+ adsorption. The bioreactor filled with immobilized protein-containing active granules showed >90% of lead removal in the contaminated water samples. The desorption of bound Pb2+ from GFP and its variants were studied by varying the pH to reuse the proteins for subsequent usage. We observed that about 70% of the GFP and its variants could be recycled and >75% of fluorescence efficiency could be recovered. Among all the variants, GFPHPDP exhibits high affinity and maintains the reusability efficiency in 7 consecutive cycles. These results suggest that genetic code engineering of cells encoding unnatural amino acids could be a next-generation microbial engineering tool for manipulating and developing the microbial strain's selective and effective removal of synthetic pollutants from the environment.


Asunto(s)
Contaminantes Ambientales , Contaminantes Químicos del Agua , Contaminantes Químicos del Agua/análisis , Agua , Contaminantes Ambientales/análisis , Ecosistema , Aminoácidos , Plomo , Adsorción , Cinética , Concentración de Iones de Hidrógeno
6.
ACS Appl Bio Mater ; 3(11): 7540-7549, 2020 Nov 16.
Artículo en Inglés | MEDLINE | ID: mdl-35019495

RESUMEN

The present study reports a method for transporting high molecular weight collagen for skin regeneration. An independent engineered enzymatic vehicle that has the ability for efficient transdermal delivery of regenerative biomaterial was developed for tissue regeneration. Collagen has been well recognized as a skin regeneration molecule due to its interaction with the extracellular matrix to stimulate skin cell growth, proliferation, and differentiation. However, the transdermal delivery of collagen poses a significant challenge due to its high molecular weight as well as a lack of efficient approaches. Here, to improve the transdermal delivery efficiency, α-1,4-glycosidic hydrolase was engineered with genetically encoded 3,4-dihydroxy-L-phenylalanine, which enhanced its biological activity as revealed by microscale thermophoresis. The remodeled catalytic pocket resulted in enhanced substrate binding activity of the enzyme with a predominant glycosaminoglycan (chondroitin sulfate) present in the extracellular matrix of the skin. The engineered enzyme rapidly opened up the skin extracellular matrix fiber (15 min) to ferry collagen across the wall, without disturbing the cellular bundle architecture. Confocal microscopy indicated that macromolecules had diffused three times deeper into the engineered enzyme-treated skin than the native enzyme-treated skin. Gene expression, histopathology, and hematology analysis also supported the penetration of macromolecules. Cytotoxicity (mammalian cell culture) and in vivo (Caenorhabditis elegans and Rattus noryegicus) studies revealed that the congener enzyme could potentially be used as a penetration enhancer, which is of paramount importance for the multimillion cosmetic industries. Hence, it offers promise as a pharmaceutical enzyme for transdermal delivery bioenhancement and dermatological applications.

7.
Biomater Sci ; 8(23): 6773-6785, 2020 Dec 07.
Artículo en Inglés | MEDLINE | ID: mdl-33141121

RESUMEN

The present work reports a new route to prepare a "smart biomaterial" by mimicking long-acting cellular growth factor showing enhanced cell-material interactions by promoting cell proliferation and angiogenesis. For that, reactive non-proteogenic amino acid 3,4-dihydroxyphenylalanine (DOPA) was genetically introduced into an intrinsic triple-helical hierarchical structure forming protein to initiate hierarchical self-assembly to form a macromolecular structure. The self-assembled scaffold displayed vascular endothelial growth factor mimicking the pro-angiogenic reactive group for repairing and remodeling of damaged tissue cells. We customized the recombinant collagen-like protein (CLP) with DOPA to promote rapid wound healing and cell migrations. Selective incorporation of catechol in variable and C-terminal region of CLP enhanced interaction between inter- and intra-triple-helical collagen molecules that resulted in a structure resembling higher-order native collagen fibril. Turbidity analysis indicated that the triple-helical CLP self-assembled at neutral pH via a catechol intra-crosslinking mechanism. After self-assembly, only DOPA-encoded CLP formed branched filamentous structures suggesting that catechol mediated network coordination. The catechol-encoded CLP also acted as a "smart material" by mimicking long-acting cellular growth factor showing enhanced cell-material interactions by promoting cell proliferation and angiogenesis. It eliminates release rate, stability, and shelf-life of hybrid growth factor conjugated biomaterials. The newly synthesized CLP has the potential to promote accelerated cell migration, pro-angiogenesis, and biocompatibility and could be used in the field of implantable medical devices and tissue engineering.


Asunto(s)
Dihidroxifenilalanina , Neovascularización Fisiológica , Factor A de Crecimiento Endotelial Vascular , Materiales Biocompatibles , Colágeno , Dihidroxifenilalanina/farmacología , Matriz Extracelular , Cicatrización de Heridas
8.
J Hazard Mater ; 392: 122257, 2020 06 15.
Artículo en Inglés | MEDLINE | ID: mdl-32109791

RESUMEN

The effectiveness of heat-inactivated fungal biomass a fermentation waste of newly isolated laccase enzyme producer Leiotrametes flavida was studied for Cr (VI) removal in water and applied for Cr (VI) removal from tannery effluent. Adsorption parameters pH, biomass concentration and contact time were optimized using Box-Behnken design of response surface methodology. The adsorption process fits the Langmuir isotherm. Thermodynamic and kinetic studies showed that the process is spontaneous at ambient temperature and followed the second-order kinetics model, respectively. The values of the kinetic model indicated that the adsorption process is a combination of physisorption and chemisorption. Chromium adsorption onto the biomass was confirmed by SEM-EDAX, FTIR, XPS and XRD analysis. XPS analysis confirmed the reduction of Cr (VI) to Cr (III). The amount of chromium adsorbed was 72.38 % and 68.33 % for water and effluent, respectively. Chromium adsorbed onto biomass was desorbed at pH 9 with 1 M NaOH. Total chromium desorbed was 61.40 and 59.38 percent from water and effluent, respectively. The amount of Cr (III) in the desorbed sample was 71 and 68 percent, respectively. The heat-inactivated biomass of Leiotrametes flavida is a suitable material for efficient Cr (VI) removal and detoxification.


Asunto(s)
Cromo/química , Polyporaceae/química , Contaminantes Químicos del Agua/química , Purificación del Agua/métodos , Adsorción , Biomasa , Fermentación , Calor , Residuos Industriales , Oxidación-Reducción , Reciclaje , Curtiembre , Termodinámica , Residuos
9.
Biomater Sci ; 7(5): 2191-2199, 2019 Apr 23.
Artículo en Inglés | MEDLINE | ID: mdl-30900708

RESUMEN

Collagen plays a critical role in the structural design of the extracellular matrix (ECM) and cell signaling in mammals, which makes it one of the most promising biomaterials with versatile applications. However, there is considerable concern regarding the purity and predictability of the product performance. At present, it is mainly derived as a mixture of collagen (different types) from animal tissues, where the selective enrichment of a particular type of collagen is generally difficult and expensive. Collagen derived from bovine sources poses the risk of transmitting diseases and can cause adverse immunologic and inflammatory responses. Hence, recombinant collagen can be a good alternative. Nevertheless, the necessity of post-translational hydroxyproline (Hyp) modification limits large-scale recombinant collagen production. Here, we recombinantly expressed the collagen-like protein (CLTP) and genetically introduced the Hyp in the CLTP to form a higher order self-assembled fibril structure, similar to human collagen. During the current study, it was observed that the Hyp incorporated CLTP protein (CLTHP) formed a stable triple helical polyproline-II like structure and self-assembled to form fibrils at neutral pH, which had an initial lag phase followed by a growth phase similar to animal collagen. In contrast, the higher order fibrillar assembly was missing in the nonhydroxylated CLTP. This study demonstrated that CLTHP self-association is based on the common underlying lateral interactions between triple helical structured proteins, where the hydroxyproline forms the significantly stable hydration network. Hence, this work will be the first fundamental empirical research for flexible modifications of recombinant collagen for structural analysis and biomedical applications.


Asunto(s)
Materiales Biocompatibles/química , Materiales Biocompatibles/farmacología , Colágeno/química , Colágeno/farmacología , Células 3T3 , Animales , Adhesión Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Hidroxiprolina/química , Ratones , Simulación de Dinámica Molecular , Conformación Proteica en Hélice alfa
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