RESUMO
The marine environment is a rich reservoir of diverse biological entities, many of which possess unique properties that are of immense value to biotechnological applications. One such example is the red fluorescent protein derived from the coral Discosoma sp. This protein, encoded by the DsRed gene, has been the subject of extensive research due to its potential applications in various fields. In the study, a variant of the red fluorescent protein was generated through random mutagenesis using the DsRed2 gene as a template. The process employed error-prone PCR (epPCR) to introduce random mutations, leading to the isolation of twelve gene variants. Among these, one variant stood out due to its unique spectral properties, exhibiting dual fluorescence emission at both 480 nm (green) and 550 nm (red). This novel variant was expressed in both Escherichia coli and zebrafish (Danio rerio) muscle, confirming the dual fluorescence emission in both model systems. One of the immediate applications of this novel protein variant is in ornamental aquaculture. The dual fluorescence can serve as a unique marker or trait, enhancing the aesthetic appeal of aquatic species in ornamental settings.
Assuntos
Antozoários , Proteína Vermelha Fluorescente , Animais , Fluorescência , Peixe-Zebra/genética , Peixe-Zebra/metabolismo , Proteínas Luminescentes/genética , Proteínas Luminescentes/metabolismo , Antozoários/genética , Antozoários/metabolismo , Biotecnologia , Proteínas de Fluorescência VerdeRESUMO
An approach is developed for the fast calculation of the interacting quantum atoms energy decomposition (IQA) from the information contained in the first order reduced density matrix only. The proposed methodology utilizes an approximate exchange-correlation density from Density Matrix Functional Theory without the need to evaluate the correlation-exchange contribution directly. Instead, weight factors are estimated to decompose the exact Vxc into atomic and pairwise contributions. In this way, the sum of the IQA contributions recovers the energy obtained from the electronic structure calculation. This method can, hence, be applied to obtain atomic contributions in excited states on the same footing as in their ground states using any method that delivers the reduced first-order density matrix. In this way, one can locate chromophores from first principles quantum chemical calculations. Test calculations on the ground and excited states of a set of small molecules indicate that the scaled atomic contributions reproduce vertical electronic transition energies calculated exactly. This approach may be useful to extend the applicability of the IQA approach in the study of large photochemical systems especially when the calculations of the second order reduced density matrices is prohibitive or not possible.
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We describe an engineered violet fluorescent protein from the lancelet Branchiostoma floridae (bfVFP). This is the first example of a GFP-like fluorescent protein with a stable fluorescent chromophore lacking an imidazolinone ring; instead, it consists of oxidized tyrosine 68 flanked by glycine 67 and alanine 69. bfVFP contains the simplest chromophore reported in fluorescent proteins and was generated from the yellow protein lanFP10A2 by two synergetic mutations, S148H and C166I. The chromophore structure was confirmed crystallographically and by high-resolution mass spectrometry. The photophysical characteristics of bfVFP (323/430 nm, quantum yield 0.33, and Ec 14,300 M-1 cm-1 ) make it potentially useful for multicolor experiments to expand the excitation range of available FP biomarkers and Förster resonance energy transfer with blue and cyan fluorescent protein acceptors.
Assuntos
Transferência Ressonante de Energia de Fluorescência , Tirosina , Alanina , Proteínas de Fluorescência Verde/química , Proteínas Luminescentes/química , Proteínas Luminescentes/genética , Mutação , Tirosina/químicaRESUMO
RESUMEN Se reporta el uso del crosslinking como tratamiento de la queratitis por Acanthamoeba en una serie de 7 pacientes quienes acudieron al Servicio de Córnea por queratitis multitratadas. Se les realizó biopsia corneal, la cual se cultivó en solución de Page. Los pacientes fueron tratados con un protocolo de PACK-CXL durante más de 5 minutos y fueron sometidos a la exposición a la luz UV-A. El edema del nuevo epitelio era de 2 cruces a las 24 horas, y desapareció a las dos semanas del procedimiento en todos los casos. El porcentaje de desepitelización basal al momento del diagnóstico fue de 75,7 por ciento. La agudeza visual mejor corregida fue de entre 20/20 y 20/30. Se concluye que el uso de crosslinking en pacientes con Acanthamoeba en fases inicales pudiera ser una opción terapéutica segura y efectiva(AU)
ABSTRACT A report is presented of the use of crosslinking as treatment for Acanthamoeba keratitis in a series of 7 patients attending the Cornea Service for multitreated keratitis. Corneal biopsy was performed, which was cultured in Page solution. The patients were treated with a PACK-CXL protocol for more than 5 minutes and subjected to UV-A light exposure. Edema of the new epithelium was 2 crosses at 24 hours and disappeared 2 weeks after the procedure in all cases. Basal de-epithelialization percentage at diagnosis was 75.7 percent. Best corrected visual acuity ranged between 20/20 and 20/30. It is concluded that the use of crosslinking in patients with Acanthamoeba keratitis in its initial stages could be a safe and effective therapeutic option(AU)
Assuntos
Humanos , Adulto , Pessoa de Meia-Idade , Idoso , Acanthamoeba/citologia , Ceratite por Acanthamoeba/diagnóstico , Ceratite por Acanthamoeba/tratamento farmacológico , Relatório de Pesquisa , Literatura de Revisão como Assunto , Bases de Dados BibliográficasRESUMO
BACKGROUND: Marine sessile organisms display a color palette that is the result of the expression of fluorescent and non-fluorescent proteins. Fluorescent proteins have uncovered transcriptional regulation, subcellular localization of proteins, and the fate of cells during development. Chromoproteins have received less attention until recent years as bioreporters. Here, we studied the properties of aeBlue, a a 25.91 kDa protein from the anemone Actinia equina. OBJECTIVE: To assess the properties of aeBlue chromoprotein under different physicochemical conditions. METHODS: In this article, during the purification of aeBlue we uncovered that it suffered a color shift when frozen. We studied the color shift by different temperature incubation and physicochemical conditions and light spectroscopy. To assess the possible structural changes in the protein, circular dichroism analysis, size exclusion chromatography and native PAGE was performed. RESULTS: We uncover that aeBlue chromoprotein, when expressed from a synthetic construct in Escherichia coli, showed a temperature dependent color shift. Protein purified at 4 °C by metal affinity chromatography exhibited a pinkish color and shifts back at higher temperatures to its intense blue color. Circular dichroism analysis revealed that the structure in the pink form of the protein has reduced secondary structure at 4 °C, but at 35 °C and higher, the structure shifts to a native conformation and Far UV- vis CD spectra revealed the shift in an aromatic residue of the chromophore. Also, the chromophore retains its properties in a wide range of conditions (pH, denaturants, reducing and oxidants agents). Quaternary structure is also maintained as a tetrameric conformation as shown by native gel and size exclusion chromatography. CONCLUSION: Our results suggest that the chromophore position in aeBlue is shifted from its native position rendering the pink color and the process to return it to its native blue conformation is temperature dependent.
Assuntos
Corantes/química , Proteínas Luminescentes/química , Pigmentos Biológicos/química , Proteínas/química , Anêmonas-do-Mar/química , Sequência de Aminoácidos , Animais , Clonagem Molecular , Cor , Corantes/metabolismo , Escherichia coli/metabolismo , Expressão Gênica , Concentração de Íons de Hidrogênio , Luz , Proteínas Luminescentes/metabolismo , Modelos Moleculares , Oxirredução , Pigmentos Biológicos/metabolismo , Conformação Proteica , Desnaturação Proteica , Proteínas/metabolismo , Espectrofotometria , TemperaturaRESUMO
An adaptive visual system is essential for organisms inhabiting new or changing light environments. The Panama Canal exhibits such variable environments owing to its anthropogenic origin and current human activities. Within the Panama Canal, Lake Gatun harbors several exotic fish species including the invasive peacock bass (Cichla monoculus), a predatory Amazonian cichlid. In this research, through spectral measurements and molecular and physiological experiments, we studied the visual system of C. monoculus and its adaptive capabilities. Our results suggest that (1) Lake Gatun is a highly variable environment, where light transmission changes throughout the canal waterway, and that (2) C. monoculus has several visual adaptations suited for this red-shifted light environment. Cichla monoculus filters short wavelengths (â¼400â nm) from the environment through its ocular media and tunes its visual sensitivities to the available light through opsin gene expression. More importantly, based on shifts in spectral sensitivities of photoreceptors alone, and on transcriptome analysis, C. monoculus exhibits extreme intraspecific variation in the use of vitamin A1/A2 chromophore in their photoreceptors. Fish living in turbid water had higher proportions of vitamin A2, shifting sensitivities to longer wavelengths, than fish living in clear water. Furthermore, we also found variation in retinal transcriptomes, where fish from turbid and clear waters exhibited differentially expressed genes that vary greatly in their function. We suggest that this phenotypic plasticity has been key in the invasion success of C. monoculus.
Assuntos
Ciclídeos/fisiologia , Luz , Visão Ocular , Percepção Visual , Animais , Meio Ambiente , Espécies Introduzidas , Lagos , Opsinas/metabolismo , PanamáRESUMO
The synthesis of hybrid pigments was made from combination of γ-Al2O3 and some organic chromophores such as carminic acid, alizarin, purpurin, curcumin, fluorescein and betacyanins. The γ-Al2O3 was obtained through sol-gel synthesis with 2-propanol and aluminium tri-sec-butoxide (ATB). This article presents some spectroscopic evidences related to the formation of aluminium complexes between coordinative unsaturated sites (CUS) of aluminium and some organic groups (carboxylic acid, quaternary ammonium and ß-keto enol) present in the chromophores structure. The physicochemical properties upcoming from a spectroscopic analysis point out that these materials can be applied in the design of new materials with potential uses in artworks and in the field of cultural heritage.
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BACKGROUND: With aging, the crystalline lens turns yellowish, which increases the absorption of wavelengths in the blue electromagnetic spectrum, reducing their photoreception in the retina. Since these wavelengths are the main stimulus in the regulation of the circadian rhythm, progressive reduction in their transmission is associated with chronic sleep disturbances and depression in elderly patients. Cataract extraction improves circadian photoreception at any age. However, lenses that block blue waves have 27% to 38% less melatonin suppression than lenses that block only ultraviolet (UV) rays. PURPOSE: To assess the depression symptoms in subjects who have had bilateral phacoemul-sification and intraocular lens (IOL) implants, one group with yellow chromophore IOLs and the other group with transparent IOLs were compared. SETTING: Association to Prevent Blindness in Mexico (APEC), Hospital "Dr Luis Sánchez Bulnes". DESIGN: This was an observational, cross-sectional, and single-center study. MATERIALS AND METHODS: Twenty-six subjects between 60 and 80 years of age, with a history of bilateral phacoemulsification and placement of the same type of IOL in both eyes from 4 to 12 months prior to the study, who attended the follow-up visits and agreed to participate in this study, and provided signed informed consent were included in the study. They were asked to answer the short version of the 15-item Geriatric Depression Scale. RESULTS: The average age of the study participants was 72.5±5.94 years. The group without chromophore included 46.1% (n=12) of the patients and the group with chromophore included 53.9% (n=14) of the patients (P=0.088). CONCLUSION: In the group of patients with IOLs that block the passage of blue light, the depression rate was 21.4%, a rate similar to that observed in the elderly population, whereas no patients in the group with transparent IOLs had depression.