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1.
Macromol Rapid Commun ; 45(4): e2300573, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37924252

RESUMEN

Mimicking triple helix and fibrillar network of collagen through collagen model peptide(CMP) with short GPO tripeptide repeats is a great challenge. Herein, a minimalistic CMP comprising only five GPO repeats [(GPO)5 ] is presented. This novel approach involves the fusion of ultrashort peptide with the synergetic power of π-system and ß-sheet formation to short CMP (GPO)5 . Accordingly, a hydrogel-forming, fluorenylmethoxycarbonyl (Fmoc)-functionalized ultrashort peptide (NFGAIL) is fused at the N-terminus and phenylalanine at the C-terminus of (GPO)5 (Fmoc-NFGAIL-(GPO)5 -F-COOH, FmP-5GPO). At room temperature, it forms a robust triple helix in aqueous buffer solution and has a relatively high melting point of 35 °C. The fluorenyl motif stabilizes the triple helix by aromatic π-π interactions as in its absence, triple helix is not formed. NFGAIL, which forms a ß-sheet, also aids in triple helix stabilization via intermolecular hydrogen bonding and hydrophobic interactions. FmP-5GPO forms highly entangled nanofibrils with a micrometer length, which have excellent cell viability. The achievement of stable triple helix and fibrils in such a short CMP(FmP-5GPO) sequence is a challenging feat, and its significance in CMP-based biomaterials is undeniable. The present strategy highlights the potential for developing new CMP sequences through intelligent tuning of fusion peptides and GPO repeats.


Asunto(s)
Colágeno , Péptidos , Péptidos/química , Colágeno/química
2.
J Environ Manage ; 365: 121300, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38955041

RESUMEN

Chromium contamination from abandoned industrial sites and inadequately managed waste disposal areas poses substantial environmental threat. Microbially induced carbonate precipitation (MICP) has shown promising, eco-friendly solution to remediate Cr(VI) and divalent heavy metals. In this study, MICP was carried out for chromium immobilization by an ureolytic bacterium Arthrobacter creatinolyticus which is capable of reducing Cr(VI) to less toxic Cr(III) via extracellular polymeric substances (EPS) production. The efficacy of EPS driven reduction was confirmed by cellular fraction analysis. MICP carried out in aqueous solution with 100 ppm of Cr(VI) co-precipitated 82.21% of chromium with CaCO3 and the co-precipitation is positively correlated with reduction of Cr(VI). The organism was utilized to remediate chromium spiked sand and found that MICP treatment decreased the exchangeable fraction of chromium to 0.54 ±â€¯0.11% and increased the carbonate bound fraction to 26.1 ±â€¯1.15% compared to control. XRD and SEM analysis revealed that Cr(III) produced during reduction, influenced the polymorph selection of vaterite during precipitation. Evaluation of MICP to remediate Cr polluted soil sample collected from Ranipet, Tamil Nadu also showed effective immobilization of chromium. Thus, A. creatinolyticus proves to be viable option for encapsulating chromium contaminated soil via MICP process, and effectively mitigating the infiltration of Cr(VI) into groundwater and adjacent water bodies.


Asunto(s)
Arthrobacter , Carbonatos , Cromo , Arthrobacter/metabolismo , Cromo/química , Carbonatos/química , Contaminantes del Suelo/metabolismo , Contaminantes del Suelo/química , Carbonato de Calcio/química
3.
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
4.
Heart Fail Rev ; 27(4): 1443-1467, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-34342769

RESUMEN

Myocardial infarction (MI) occurs due to the obstruction of coronary arteries, a major crux that restricts blood flow and thereby oxygen to the distal part of the myocardium, leading to loss of cardiomyocytes and eventually, if left untreated, leads to heart failure. MI, a potent cardiovascular disorder, requires intense therapeutic interventions and thereby presents towering challenges. Despite the concerted efforts, the treatment strategies for MI are still demanding, which has paved the way for the genesis of biomaterial applications. Biomaterials exhibit immense potentials for cardiac repair and regeneration, wherein they act as extracellular matrix replacing scaffolds or as delivery vehicles for stem cells, protein, plasmids, etc. This review concentrates on natural, synthetic, and hybrid biomaterials; their function; and interaction with the body, mechanisms of repair by which they are able to improve cardiac function in a MI milieu. We also provide focus on future perspectives that need attention. The cognizance provided by the research results certainly indicates that biomaterials could revolutionize the treatment paradigms for MI with a positive impact on clinical translation.


Asunto(s)
Materiales Biocompatibles , Infarto del Miocardio , Materiales Biocompatibles/uso terapéutico , Matriz Extracelular/metabolismo , Humanos , Miocardio/metabolismo , Ingeniería de Tejidos/métodos
5.
Bioorg Med Chem ; 50: 116460, 2021 11 15.
Artículo en Inglés | MEDLINE | ID: mdl-34757293

RESUMEN

Protein modifications through genetic code engineering have a remarkable impact on macromolecule engineering, protein translocation, protein-protein interaction, and cell biology. We used the newly developed molecular biology approach, genetic code engineering, for fine-tuning of proteins for biological availability. Here, we have introduced 3, 4-dihydroxy-l-phenylalanine in recombinant proteins by selective pressure incorporation method for protein-based cell labeling applications. The congener proteins treated with tyrosinase convert 3, 4-dihydroxy-l-phenylalanine to dopaquinone for strain-promoted click chemistry. Initially, the single-step Strain-Promoted Oxidation-Controlled Cyclooctyne-1,2-quinone Cycloaddition was studied using tyrosinase catalyzed congener protein and optimized the temporally controlled conjugation with (1R,8S,9s)-Bicyclo[6.1.0]non-4-yn-9-ylmethanol. Then, the feasibility of tyrosinase-treated congener annexin A5 with easily reactive quinone functional moiety was conjugated with fluorescent tag dibenzocyclooctyne-PEG4-TAMRA for labeling of apoptotic cells. Thus, the congener proteins-based products demonstrate selective cell labeling and apoptosis detection in EA.hy926 cells even after the protein modifications. Hence, genetic code engineering can be coupled with click chemistry to develop various protein-based fluorescent labels.


Asunto(s)
Benzoquinonas/farmacología , Dihidroxifenilalanina/análogos & derivados , Dihidroxifenilalanina/farmacología , Monofenol Monooxigenasa/metabolismo , Apoptosis/efectos de los fármacos , Benzoquinonas/química , Benzoquinonas/metabolismo , Células Cultivadas , Química Clic , Dihidroxifenilalanina/química , Dihidroxifenilalanina/metabolismo , Ingeniería Genética , Humanos , Estructura Molecular , Monofenol Monooxigenasa/química , Monofenol Monooxigenasa/genética , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo
7.
Langmuir ; 33(47): 13504-13514, 2017 11 28.
Artículo en Inglés | MEDLINE | ID: mdl-29135262

RESUMEN

Charge-transfer (CT) gel materials obtained from low-molecular-weight (LMW) compounds through a supramolecular self-assembly approach have received fascinating attention by many researchers because of their interesting material property and potential applications. However, most of the CT gel materials constructed were of organogels while the construction of CT gels in the form of a hydrogel is a challenge because of the solubility issue in water, which considerably limits the use of CT hydrogels. Herein, for the first time, we report a new LMW gelator [Nα-(fluorenylmethoxycarbonyl)-Nε-(δ-butyric-1-pyrenyl)-l-lysine, (FmKPy)], composed of two functional moieties such as fluorenylmethoxycarbonyl and pyrene, which not only parade both hydro and organo (ambidextrous) supramolecular gel formation but also exhibit CT ambidextrous gels when mixed with an electron acceptor such as 2,4,7-trinitro-9-fluorenone (TNF). This finding is significant as the established CT organogelator in the literature did not form an organogel in the absence of an electron acceptor or lose their gelation property upon the addition of the acceptor. CT between pyrene and TNF was confirmed by the color change as well as the appearance of the CT band in the visible region of the absorption spectrum. CT between FmKPy and TNF was supported by the solvent dilution method using tetrahydrofuran as the gel breaker and pyrene fluorescence quenching in the case compound containing pyrene and TNF. The morphology of FmKPy ambidextrous gels indicates the fibrous nature while the self-assembled structure is primarily stabilized by π-π stacking among fluorenyl and pyrenyl moieties and hydrogen bonding between amide groups. The FmKPy-TNF CT ambidextrous gel retains the fibrous nature; however, the size of the fibers changed. In FmKPy-TNF CT gels, TNF is intercalated between pyrene moieties in the self-assembled structure as confirmed by fluorescence quenching and powder X-ray diffraction. The FmKPy ambidextrous gel exhibits significant properties such as low minimum gelation concentration (MGC), thixotropic nature, pH stimuli response, and high thermal stability. Upon the addition of TNF, the FmKPy-TNF CT ambidextrous gel maintains all these properties except MGC which increased for FmKPy-TNF. Because pyrene-based LMW organogels have been developed widely for many applications while their hydrogels were limited, the current finding of the pyrene-based ambidextrous fluorescent gel with the CT property provides a wide opportunity to use FmKPy as a soft material maker and also for potential applications in fields like surface coating, three-dimensional printing, and so forth.

8.
Int J Syst Evol Microbiol ; 67(11): 4820-4824, 2017 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-28984219

RESUMEN

Cells of strain SW33T, isolated from the seawater of Asan Bay, Republic of Korea, were characterized as Gram-stain-negative, aerobic, rod-shaped, motile and non-spore-forming. Phylogenetic analysis revealed that strain SW33T belonged to the genus Psychrosphaera and clustered distantly with the other genera in the family Pseudoalteromonadaceae in the phylogenetic tree. The 16S rRNA sequences of strain SW33T revealed high similarities to Psychrosphaera saromensis SA4-48T (98.7 %), Psychrosphaera haliotis KDW4T (97.4 %) and Psychrosphaera aestuarii PSC101T (97.3 %). The major fatty acids were C16 : 0 (27.9 %), summed feature 3 (32.2 %) and summed feature 8 (17.2 %). The predominant quinone was Q-8, and the polar lipid profile consisted of diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol and an unidentified amino lipid. The DNA G+C content was 38.3 mol%. The DNA-DNA relatedness values with the three species of Psychrosphaera saromensis KCTC 23240T, Psychrosphaera haliotis KCTC 22500T and Psychrosphaera aestuarii KCTC 32274T were 22, 23 and 18 %, respectively. Based on the phenotypic characteristics and taxonomic analyses, we propose that strain SW33T represents a novel species within the genus Psychrosphaera, for which the name Psychrosphaera aquimarina sp. nov. with the type strain SW33T (=KCTC 52743T=CICC 24249T) is proposed.


Asunto(s)
Gammaproteobacteria/clasificación , Filogenia , Agua de Mar/microbiología , Técnicas de Tipificación Bacteriana , Composición de Base , Bahías , ADN Bacteriano/genética , Ácidos Grasos/química , Gammaproteobacteria/genética , Gammaproteobacteria/aislamiento & purificación , Hibridación de Ácido Nucleico , Fosfolípidos/química , ARN Ribosómico 16S/genética , República de Corea , Análisis de Secuencia de ADN , Vitamina K 2/análogos & derivados , Vitamina K 2/química
9.
Angew Chem Int Ed Engl ; 53(49): 13360-4, 2014 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-25195781

RESUMEN

Misaminoacylation of 3,4-dihydroxyphenylalanine (Dopa) molecules to tRNA(Tyr) by endogenous tyrosyl-tRNA synthetase allowed the quantitative replacement of tyrosine residues with a yield of over 90 % by an in vivo residue-specific incorporation strategy, to create, for the first time, engineered mussel adhesive proteins (MAPs) in Escherichia coli with a very high Dopa content, close to that of natural MAPs. The Dopa-incorporated MAPs exhibited a superior surface adhesion and water resistance ability by assistance of Dopa-mediated interactions including the oxidative Dopa cross-linking, and furthermore, showed underwater adhesive properties comparable to those of natural MAPs. These results propose promising use of Dopa-incorporated engineered MAPs as bioglues or adhesive hydrogels for practical underwater applications.


Asunto(s)
Bivalvos/química , Dihidroxifenilalanina/química , Ingeniería de Proteínas/métodos , Proteínas/química , Adhesividad , Secuencia de Aminoácidos , Animales , Biomimética , Bivalvos/genética , Dihidroxifenilalanina/genética , Escherichia coli/genética , Datos de Secuencia Molecular , Proteínas/genética , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Agua/química
10.
Int J Biol Macromol ; 266(Pt 1): 130999, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38521303

RESUMEN

Collagen, a key component of extracellular matrix serves as a linchpin for maintaining structural integrity and functional resilience. Concerns over purity and immunogenicity of animal-derived collagens have spurred efforts to develop synthetic collagen-based biomaterials. Despite several collagen mimics, there remains limited exploration of non-immunogenic biomaterials with the capacity for effective self-assembly. To combat the lacuna, collagen like protein (CLP) variants were rationally designed and recombinantly expressed, incorporating human telopeptide sequences (CLP-N and CLP-NC) and bioactive binding sites (CLP-NB). Circular dichroism analyses of the variants confirmed the triple helical conformation, with variations in thermal stability and conformation attributed to the presence of telopeptides at one or both ends of CLP. The variants had propensity to form oligomers, setting the stage for fibrillogenesis. The CLP variants were biocompatible, hemocompatible and supported cell proliferation and migration, particularly CLP-NB with integrin-binding sites. Gene expression indicated a lack of significant upregulation of inflammatory markers, highlighting the non-immunogenic nature of these variants. Lyophilized CLP scaffolds maintained their triple-helical structure and offered favorable biomaterial characteristics. These results accentuate the potential of designed CLP variants in tissue engineering, regenerative medicine and industrial sectors, supporting the development of biocompatible scaffolds and implants for therapeutic and cosmetic purposes.


Asunto(s)
Ingeniería de Tejidos , Ingeniería de Tejidos/métodos , Humanos , Colágeno/química , Materiales Biocompatibles/química , Proliferación Celular/efectos de los fármacos , Andamios del Tejido/química , Biomimética/métodos , Animales , Materiales Biomiméticos/química , Materiales Biomiméticos/farmacología , Movimiento Celular/efectos de los fármacos
11.
Colloids Surf B Biointerfaces ; 238: 113908, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38677153

RESUMEN

In response to the critical demand for advancements in coronary artery stents, this study addresses the challenges associated with arterial recoil and restenosis post-angioplasty and the imperative to encourage rapid re-endothelialization for minimizing thrombosis risks. We employed an innovative approach inspired by mussel adhesion, incorporating placental anticoagulant protein (AnnexinV) on stent design. The introduction of a post-translationally modified catecholic amino acid L-3,4-dihydroxyphenylalanine (L-Dopa), mimicking mussel characteristics, allowed for effective surface modification of Stainless steel stents through genetic code engineering in AnnexinV (AnxDopa). The efficacy of AnxDopa was analyzed through microscale thermophoresis and flow cytometry, confirming AnxDopa's exceptional binding with phosphatidylserine and activated platelets. AnxDopa coated stainless steel demonstrates remarkable bio-, hemo-, and immuno-compatibility, preventing smooth muscle cell proliferation, platelet adhesion, and fibrin formation. It acts as an interface between the stent and biological fluid, which facilitates the anticoagulation and rapid endothelialization. Surface modification of SS verified through XPS analysis and contact angle measurement attests to the efficacy of AnxDopa mediated surface modification. The hydrophilic nature of the AnxDopa-coated surface enhanced the endothelialization through increased protein absorption. This approach represents a significant stride in developing coronary stents with improved biocompatibility and reduced restenosis risks, offering valuable contributions to scientific and clinical realms alike.


Asunto(s)
Materiales Biocompatibles Revestidos , Stents , Humanos , Materiales Biocompatibles Revestidos/química , Materiales Biocompatibles Revestidos/farmacología , Vasos Coronarios/efectos de los fármacos , Adhesividad Plaquetaria/efectos de los fármacos , Anticoagulantes/farmacología , Anticoagulantes/química , Propiedades de Superficie , Proliferación Celular/efectos de los fármacos , Acero Inoxidable/química , Plaquetas/efectos de los fármacos , Plaquetas/metabolismo , Miocitos del Músculo Liso/efectos de los fármacos , Miocitos del Músculo Liso/metabolismo , Miocitos del Músculo Liso/citología , Animales , Levodopa/química , Levodopa/farmacología
12.
J Biomed Mater Res A ; 2024 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-38553971

RESUMEN

Bacterial collagen, produced via recombinant DNA methods, offers advantages including consistent purity, customizable properties, and reduced allergy potential compared to animal-derived collagen. Its controlled production environment enables tailored features, making it more sustainable, non-pathogenic, and compatible with diverse applications in medicine, cosmetics, and other industries. Research has focused on the engineering of collagen-like proteins to improve their structure and function. The study explores the impact of introducing tyrosine, an amino acid known for its role in fibril formation across diverse proteins, into a newly designed bacterial collagen-like protein (Scl2), specifically examining its effect on self-assembly and fibril formation. Biophysical analyses reveal that the introduction of tyrosine residues didn't compromise the protein's structural stability but rather promoted self-assembly, resulting in the creation of nanofibrils-a phenomenon absent in the native Scl2 protein. Additionally, stable hydrogels are formed when the engineered protein undergoes di-tyrosine crosslinking under light exposure. The hydrogels, shown to support cell viability, also facilitate accelerated wound healing in mouse fibroblast (NIH/3T3) cells. These outcomes demonstrate that the targeted inclusion of functional residues in collagen-like proteins enhances fibril formation and facilitates the generation of robust hydrogels using riboflavin chemistry, presenting promising paths for research in tissue engineering and regenerative medicine.

13.
Biochem Biophys Res Commun ; 440(4): 509-14, 2013 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-24080380

RESUMEN

Here we enhanced the stability and biophysical properties of mRFP1 through a combination of canonical and non-canonical amino acid mutagenesis. The global replacement of proline residue with (2S, 4R)-4-fluoroproline [(4R)-FP] into mRFP1 led to soluble protein but lost its fluorescence, whereas (2S, 4S)-4-fluoroproline [(4S)-FP] incorporation resulted in insoluble protein. The bioinformatics analysis revealed that (4R)-FP incorporation at Pro63 caused fluorescence loss due to the steric hindrance of fluorine atom of (4R)-FP with the chromophore. Therefore, Pro63 residue was mutated with the smallest amino acid Ala to maintain non coplanar conformation of the chromophore and helps to retain its fluorescence with (4R)-FP incorporation. The incorporation of (4R)-FP into mRFP1-P63A showed about 2-3-fold enhancement in thermal and chemical stability. The rate of maturation is also greatly accelerated over the presence of (4R)-FP into mRFP1-P63A. Our study showed that a successful enhancement in the biophysical property of mRFP1-P63A[(4R)-FP] using non-canonical amino acid mutagenesis after mutating non-permissive site Pro63 into Ala.


Asunto(s)
Fluorescencia , Proteínas Luminiscentes/química , Prolina/análogos & derivados , Fenómenos Biofísicos , Calor , Proteínas Luminiscentes/genética , Mutagénesis , Prolina/química , Prolina/genética , Estabilidad Proteica , Proteína Fluorescente Roja
14.
Trends Biotechnol ; 41(2): 165-183, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-35908989

RESUMEN

Genetic code expansion (GCE) enables directed incorporation of noncoded amino acids (NCAAs) and unnatural amino acids (UNAAs) into the active core that confers dedicated structure and function to engineered proteins. Many protein biomaterials are tandem repeats that intrinsically include NCAAs generated through post-translational modifications (PTMs) to execute assigned functions. Conventional genetic engineering approaches using prokaryotic systems have limited ability to biosynthesize functionally active biomaterials with NCAAs/UNAAs. Codon suppression and reassignment introduce NCAAs/UNAAs globally, allowing engineered proteins to be redesigned to mimic natural matrix-cell interactions for tissue engineering. Expanding the genetic code enables the engineering of biomaterials with catechols - growth factor mimetics that modulate cell-matrix interactions - thereby facilitating tissue-specific expression of genes and proteins. This method of protein engineering shows promise in achieving tissue-informed, tissue-compliant tunable biomaterials.


Asunto(s)
Materiales Biocompatibles , Código Genético , Proteínas/genética , Ingeniería Genética , Aminoácidos/metabolismo , Aminas
15.
Appl Biochem Biotechnol ; 195(2): 992-1013, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36260248

RESUMEN

The sudden rise in the demand has led to large-scale production of hydroxychloroquine (HCQ) in the global market for various diseases such as malaria, rheumatic arthritis, and systemic lupus erythematous and prophylactic treatment of early SARS-CoV-2 outbreak. Thorough monitoring of HCQ intake patients is in high demand; hence, we have developed a redox amino acid encoded fluorescent protein-based electrochemical biosensor for sensitive and selective detection of HCQ. This electrochemical biosensor is generated based on the two-electron transfer process between redox amino acid (3,4-dihydroxy-L-phenylalanine, DOPA) encoded bio-redox protein and the HCQ forms the conjugate. The DOPA residue in the bio-redox protein specifically binds with HCQ, thereby producing a remarkable electrochemical response on the glassy carbon electrode. Experimental results show that the developed biosensor selectively and sensitively detects the HCQ in spiked urine samples. The reagent-free bio-redox capacitor detects HCQ in the range of 90 nM to 4.4 µM in a solution with a detection limit of 58 nM, signal to noise ratio of 3:1, and strong anti-interference ability. Real-time screening, quantification, and relative mean recoveries of HCQ on spiked urine samples were monitored through electron shuttling using bio-redox protein and were found to be 97 to 101%. Overall, the developed bio-redox protein-based sensor has specificity, selectivity, reproducibility, and sensitivity making it potentially attractive for the sensing of HCQ and also applicable to clinical research.


Asunto(s)
COVID-19 , Hidroxicloroquina , Humanos , Hidroxicloroquina/metabolismo , Hidroxicloroquina/uso terapéutico , Aminoácidos/metabolismo , Reproducibilidad de los Resultados , SARS-CoV-2 , Tratamiento Farmacológico de COVID-19 , Oxidación-Reducción , Dihidroxifenilalanina
16.
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
17.
Chem Asian J ; 18(4): e202201235, 2023 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-36567257

RESUMEN

While a considerable number of ultra-short/short amyloid peptides have been reported to form 3D supramolecular hydrogels, they all possess high minimum gelation concentration (MGC) (≥1 wt%), which preclude their applications. In this context, we demonstrate that functionalisation of a well-known amyloidogenic ultra-short peptide fragment NFGAIL (IAPf) of human Islet amyloid polypeptide with a π-system (Fluorenyl, Fm) at the N-terminus of the peptide (Fm-IAPf) yield not only highly thermostable hydrogel at physiological pH but also exhibited super gelator nature as the MGC (0.08 wt%) falls below 0.1 wt%. Various experimental results confirmed that aromatic π-π interactions from fluorenyl moieties and hydrogen bonding interactions between the IAPf drive the self-assembly/fibril formation. Fm-IAPf is the first super hydrogelator derived from amyloid-based ultra-short peptides, to the best of our knowledge. We strongly believe that this report, i. e., functionalization of an amyloid peptide with π-system, provides a lead to develop super hydrogelators from other amyloid-forming peptide fragments for their potential applications.


Asunto(s)
Polipéptido Amiloide de los Islotes Pancreáticos , Fragmentos de Péptidos , Humanos , Fragmentos de Péptidos/química , Polipéptido Amiloide de los Islotes Pancreáticos/química , Amiloide/química
18.
Parasitol Res ; 110(1): 381-8, 2012 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-21732183

RESUMEN

Integrated vector control is an effective and essential part of any successful vector control program. Increasing insecticide resistance requires strategies to prolong the use of highly effective vector control compounds. Synergistic activity between current effective pesticides is a powerful tool and is one such strategy. In the current study, Cyt1A from Bacillus thurigiensis subsp. israelensis and Bacillus sphaericus B101H5aH5b Bs were evaluated for the synergistic activity against B. sphaericus-resistant strains of Anopheles stephensi. The combinations of Cyt1A and B. sphaericus were found to act synergistically and were greatly enhanced at different ratios. A ratio of 1:4 of Cyt1A and Bs was 13,200-fold more toxic at LC(90) against the Bs-resistant strains of A. stephensi than was Bs alone and this high level of activity resulted from synergism between Cyt1A toxin and Bs. Our results therefore suggest that Cyt1A may enhance toxicity by facilitating the binding or insertion of the binary toxins to the microvillar membrane.


Asunto(s)
Anopheles/efectos de los fármacos , Bacillus/metabolismo , Toxinas Bacterianas/farmacología , Sinergismo Farmacológico , Insecticidas/farmacología , Animales , Toxinas Bacterianas/aislamiento & purificación , Análisis de Supervivencia
19.
Biomater Adv ; 139: 212997, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35882145

RESUMEN

Despite the potential tunable properties of blank slate collagen-like proteins (CLP), an alternative to animal-originated collagen, assembling them into a stable 3D hydrogel to mimic extracellular matrix is a challenge. To address this constraint, the CLP (without hydroxyproline, CLPpro) and its variants encoding functional unnatural amino acids such as hydroxyproline (CLPhyp) and 3,4-dihydroxyphenylalanine (CLPdopa) were generated through genetic code engineering for 3D hydrogel development. The CLPhyp and CLPdopa were chosen to enhance the intermolecular hydrogen bond interaction through additional hydroxyl moiety and thereby facilitate the self-assembly into a fibrillar network of the hydrogel. Hydrogelation was induced through genipin as a cross-linker, enabling intermolecular cross-linking to form a hydrogel. Spectroscopic and rheological analyses confirmed that CLPpro and its variants maintained native triple-helical structure, which is necessary for its function, and viscoelastic nature of the hydrogels, respectively. Unlike CLPpro, the varients (CLPhyp and CLPdopa) increased pore size formation in the hydrogel scaffold, facilitating 3T3 fibroblast cell interactions. DSC analysis indicated that the stability of the hydrogels got increased upon the genetic incorporation of hydroxyproline (CLPhyp) and dopa (CLPdopa) in CLPpro. In addition, CLPdopa hydrogel was found to be relatively stable against collagenase enzyme compared to CLPpro and CLPhyp. It is the first report on 3D biocompatible hydrogel preparation by tailoring CLP sequence with non-natural amino acids. These next-generation tunable CLP hydrogels open a new venue to design synthetic protein-based biocompatible 3D biomaterials for tissue engineering applications.


Asunto(s)
Hidrogeles , Ingeniería de Tejidos , Animales , Colágeno/metabolismo , Matriz Extracelular , Hidrogeles/química , Hidroxiprolina/metabolismo , Ingeniería de Tejidos/métodos
20.
J Biomol Struct Dyn ; 40(12): 5577-5587, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-33438527

RESUMEN

Abnormal protein aggregation in the nervous tissue leads to several neurodegenerative disorders like Alzheimer's disease (AD). In AD, accumulation of the amyloid beta (Aß) peptide is proposed to be an early important event in pathogenesis. Significant research efforts are devoted so as to understand the Aß misfolding and aggregation. Molecular dynamics (MD) simulations complement experiments and provide structural information at the atomic level with dynamics without facing the same experimental limitations. Artificial missense mutations are employed experimentally and computationally for providing insights into the structure-function relationships of amyloid-ß in relation to the pathologies of AD. Present work describes the MD simulations for 100 ns so as to probe the structural and conformational dynamics of Aß1-42 assemblies and its mutants. Essential dynamics analysis with respect to conformational deviation of Cα was evaluated to identify the largest residual fluctuation of Cα. Conformational stability of all Aß mutants was analyzed by computing RMSD, deciphering the convergence is reached in the last 20 ns in all replicas. To highlight the low frequency mode of motion corresponding to the highest amplitude, atomic displacements seen in trajectory, distance pair principal component analysis (dpPCA) was performed, which adumbrated mutations strongly affect the conformational dynamics of investigated model when compared with wild type. Dynamic cross correlation matrix (DCCM) also suggests the conserved interactions of wild Aß and imply mutations in ß3-ß4 loop region induce deformity and residual fluctuations as observed from simulation. Present study indicate the mutational energy landscape which induces deformation leading to fibrillation.Communicated by Ramaswamy H. Sarma.


Asunto(s)
Enfermedad de Alzheimer , Péptidos beta-Amiloides , Enfermedad de Alzheimer/metabolismo , Péptidos beta-Amiloides/química , Humanos , Simulación de Dinámica Molecular , Mutación , Fragmentos de Péptidos/química , Análisis de Componente Principal
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