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1.
J Zhejiang Univ Sci B ; 25(4): 293-306, 2024 Apr 15.
Artículo en Inglés, Chino | MEDLINE | ID: mdl-38584092

RESUMEN

The oyster mushroom (Pleurotus spp.) is one of the most widely cultivated mushroom species globally. The present study investigated the effect of synbiotics on the growth and quality of Pleurotus ostreatus and Pleurotus pulmonarius. Different synbiotics formulations were applied by spraying mushroom samples daily and measuring their growth parameters, yield, biological efficiency, proximate composition, mineral content, total phenolic content (TPC), and diphenyl-1-picryl-hydrazyl (DPPH) radical scavenging activity. Results demonstrated that the most significant yield of oyster mushrooms was harvested from synbiotics sprayed with inulin and Lactobacillus casei (56.92 g). Likewise, the highest biological efficiency obtained with a similar synbiotic was 12.65%. Combining inulin and L. casei was the most effective method of improving the mushrooms' growth performance and nutrient content in both samples. Furthermore, synbiotics that combined inulin and L. casei resulted in the highest TPC (20.550 mg gallic acid equivalent (GAE)/g dry extract (DE)) in white oyster mushrooms (P. ostreatus). In comparison, in grey mushroom (P. pulmonarius) the highest TPC was yielded by L. casei (1.098 mg GAE/g DE) followed by inulin and L. casei (1.079 mg GAE/g DE). The DPPH results indicated that the oyster mushroom could be an efficient antioxidant. The results revealed that applying synbiotics improved the mushrooms' quality by increasing their antioxidant capacity with higher amounts of phenolic compounds and offering better health benefits with the increased levels of mineral elements. Together, these studies demonstrated the potential of using synbiotics as a biofertilizer, which is helpful for mushroom cultivation; therefore, it might solve the challenge of inconsistent quality mushroom growers face.


Asunto(s)
Pleurotus , Simbióticos , Pleurotus/química , Antioxidantes , Inulina , Fenoles , Ácido Gálico , Minerales
2.
Mol Biotechnol ; 2024 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-38507018

RESUMEN

The world of pharmaceutical research has been increasingly turning its gaze toward the treasure trove of natural products in search of novel drugs and therapeutic agents. Amidst the vast array of medicinal plants that dot our planet, the Asclepiadaceae family unexplored species have piqued the interest of researchers. Both medicinal plants are indigenous to specific regions and have been integral to traditional medicine systems for centuries. This systematic review aims to provide a comprehensive summary of the current knowledge regarding the phytochemical profile of these plants and their potential implications in the pharmaceutical industry. These plants are rich in phytochemical constituents such as alkaloids, flavonoids, terpenoids, phenolic compounds, glycosides, and saponins. These constituents have been found to exhibit a range of pharmacological activities. They have antimicrobial properties, providing a defense against various microorganisms. They also show anti-inflammatory properties, helping to reduce inflammation in the body. In addition, these plants have antioxidant properties, which help protect cells from damage by harmful free radicals. They have shown anticancer activity, offering potential for cancer treatment. Their neuroprotective properties could be beneficial in treating neurological disorders. The analgesic properties of these plants could be harnessed for pain relief. Furthermore, they have antidiabetic properties, offering potential for diabetes management. The hope is that this review will stimulate further research into these fascinating plants and contribute to discovering new drugs from natural herbs.

3.
Vet Res Commun ; 48(1): 29-37, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37840088

RESUMEN

An edible bird nest is a product of the solidified saliva secretion from a few different swiftlet's species, during the breeding season. But the high impurities in A. maximus and C. esculent nests make them less ideal to be consumed. Eggshells and guano are the major contaminants contributing to the nitrite and nitrates contents. However, recent studies have shown significant medicinal and cosmetic applications of edible bird nest like anti-viral, anti-inflammatory, enhancing bone strength, and anti-aging. Thus, the high demand for edible bird nest in the global market to explore its potential application has improved from swiftlet farming activities to the cleaning process. Recent studies have shown the use of immobilized enzymes like keratinase for the removal of contaminants. The current review discusses the importance of Swiftlet bird nest, its application, and commercialization.


Asunto(s)
Aves , Nitritos , Animales , Nitratos
4.
Int J Biol Macromol ; 253(Pt 2): 126492, 2023 Dec 31.
Artículo en Inglés | MEDLINE | ID: mdl-37634772

RESUMEN

The unscientific disposal of the most abundant crustacean wastes, especially those derived from marine sources, affects both the economy and the environment. Strategic waste collection and management is the need of the hour. Sustainable valorization approaches have played a crucial role in solving those issues as well as generating wealth from waste. The shellfishery wastes are rich in valuable bioactive compounds such as chitin, chitosan, minerals, carotenoids, lipids, and other amino acid derivatives. These value-added components possessed pleiotropic applications in different sectors viz., food, nutraceutical, cosmeceutical, agro-industrial, healthcare, and pharmaceutical sectors. The manuscript covers the recent status, scope of shellfishery management, and different bioactive compounds obtained from crustacean wastes. In addition, both sustainable and conventional routes of valorization approaches were discussed with their merits and demerits along with their combinations. The utilization of nano and microtechnology was also included in the discussion, as they have become prominent research areas in recent years. More importantly, the future perspectives of crustacean waste management and other potential valorization approaches that can be implemented on a large scale.


Asunto(s)
Quitosano , Administración de Residuos , Animales , Quitina/química , Crustáceos/metabolismo , Alimentos Marinos
5.
Mol Biotechnol ; 65(6): 833-848, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-36544065

RESUMEN

In plant development, flowering is the most widely studied process. Floral forms show large diversity in different species due to simple variations in basic architecture. To determine the floral gene expression during the past decade, MADS-box genes have identified as key regulators in both reproductive and vegetative plant development. Traditional genetics and functional genomics tools are now available to elucidate the expression and function of this complex gene family on a much larger scale. Moreover, comparative analysis of the MADS-box genes in diverse flowering and non-flowering plants, boosted by various molecular technologies such as ChIP and next-generation DNA sequencing, contributes to our understanding of how this important gene family has expanded during the evolution of land plants. Likewise, the big data analysis revealed combined activity of transcriptional regulators and floral organ identity factors regulate the flower developmental programs. Thus, with the help of cutting-edge technologies like RNA-Sequencing, sex determination is now better understood in few non-model plants Therefore, the recent advances in next-generation sequencing (NGS) should enable researchers to identify the full range of floral gene functions, which will significantly help to understand plant development and evolution. This review summarizes the floral homeotic genes in model and non-model species to understand the flower development genes and dioecy evolution.


Asunto(s)
Proteínas de Dominio MADS , Plantas , Proteínas de Dominio MADS/genética , Proteínas de Dominio MADS/metabolismo , Plantas/genética , Plantas/metabolismo , Desarrollo de la Planta , Fenotipo , Secuenciación de Nucleótidos de Alto Rendimiento , Flores , Regulación de la Expresión Génica de las Plantas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Filogenia
6.
Comb Chem High Throughput Screen ; 26(11): 1945-1959, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36366840

RESUMEN

SARS-CoV-2 is a disease that endangers both human life and the economy. There was an 11- month period of relative evolutionary standstill following the appearance of SARS-CoV-2 in late 2019. However, the emergence of clusters of mutations known as' variants of concern 'with variable viral properties such as transmissibility and antigenicity defined the evolution of SARS-CoV-2. Several efforts have been made in recent months to understand the atomic level properties of SARS-CoV-2. A review of the literature on SARS-CoV-2 mutations is offered in this paper. The critical activities performed by different domains of the SARS-CoV-2 genome throughout the virus's entry into the host and overall viral life cycle are discussed in detail. These structural traits may potentially pave the way for the development of a vaccine and medication to combat the SARS-CoV-2 sickness.


Asunto(s)
COVID-19 , Humanos , COVID-19/prevención & control , SARS-CoV-2/genética , Desarrollo de Vacunas , Mutación , Fenotipo
7.
Malays J Med Sci ; 29(2): 55-68, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35528808

RESUMEN

Background: Diarrhoeagenic verotoxin producing non-O157 Escherichia coli (VTEC) are associated with endemic infantile diarrhoea-causing morbidity and mortality worldwide. VTEC can also cause severe illness and has an impact on outbreaks, especially in developing countries. This study aims to investigate the prevalence and characterisation of VTEC and their association in causing infectious diarrhoea among Malaysian children. Methods: Standard microbiological techniques identified a total of 137 non-repeated, clinically significant E. coli isolates. Serological assays discerned non-O157 E. coli serogroup, subjected to virulence screen (VT1 and VT2) by a polymerase chain reaction (PCR). Results: Different PCR sets characterised the 49 clinical isolates of sorbitol positive non-O157 E. coli. Twenty-nine isolates harboured verotoxin genes associated with diarrhoea among children (≤ 5 years old). Among the 29 (59.18%) strains of verotoxin producing E. coli, genotypes VT1 and VT2 were detected in 21 (42.85%) and 5 (10.20%) isolates respectively, while both VT1 and VT2 genes were confirmed in 3 (6.12%) isolates. Conclusion: This study evaluates on the prevalence, serological characteristics and antimicrobial susceptibility patterns of VTEC diarrhoea affected children (≤ 5 years old). Besides, the prevalence of verotoxin gene was determined as a root cause of diarrhoea among Malaysian children.

8.
Int J Food Microbiol ; 373: 109714, 2022 Jul 16.
Artículo en Inglés | MEDLINE | ID: mdl-35567891

RESUMEN

One of the most significant and difficult jobs in food sustainability, is to make use of waste in the vegetable and fruit processing sectors. The discarded fruits along with their waste materials, is anticipated to have potential use for further industrial purposes via extraction of functional ingredients, extraction of bioactive components, fermentation. As a result of its abundant availability, simplicity and safe handling, and biodegradability, pineapple waste is now the subject of extensive research. It is regarded as a resource for economic development. This vast agro-industrial waste is being investigated as a low-cost raw material to produce a variety of high-value-added goods. Researchers have concentrated on the exploitation of pineapple waste, particularly for the extraction of prebiotic oligosaccharides as well as bromelain enzyme, and as a low-cost source of fibre, biogas, organic acids, phenolic antioxidants, and ethanol. Thus, this review emphasizes on pineapple waste valorisation approaches, extraction of bioactive and functional ingredients together with the advantages of pineapple waste to be used in many areas. From the socioeconomic perspective, pineapple waste can be a new raw material source to the industries and may potentially replace the current expensive and non-renewable sources. This review summarizes various approaches used for pineapple waste processing along with several important value-added products gained which could contribute towards healthy food and a sustainable environment.


Asunto(s)
Ananas , Antioxidantes , Biotecnología , Frutas , Residuos
9.
Curr Microbiol ; 79(5): 151, 2022 Apr 09.
Artículo en Inglés | MEDLINE | ID: mdl-35397007

RESUMEN

Aquilaria malaccensis, the resinous agarwood, is highly valued in the perfumery and medicinal industry. The formation of fragrant agarwood resin inconsistently by various fungi is still not clearly understood. The current study investigated the agarwood quality and fungal diversity in artificially inoculated and naturally infected A. malaccensis. The chemical analysis of volatile compounds of agarwood was performed using the Solid Phase Micro Extraction (SPME) method, and the identification of fungi was made through a morphological observation using a light microscope. Gas chromatography analysis revealed the presence of essential compounds related to high-quality agarwood, such as 4-phenyl-2-butanone, ß-selinene, α-bulnesene, and agarospirol in both artificially inoculated and naturally infected agarwood but with some differences in the abundance. Further studies on the fungi associated with agarwood volatile compounds formation showed a total of ten fungal group isolates, which were identified based on morphological and molecular studies. The study revealed that agarwood from both artificial and natural sources were naturally infected with Fusarium, Botryosphaeria, Aspergillus, Schizophyllum, Phanerochaete, Lasiodiplodia, Polyporales, and Ceriporia species. This study has offered a potential opportunity to research further the promising development of fungal strains for artificial inducement of high-quality agarwood formation from A. malaccensis trees.


Asunto(s)
Ascomicetos , Fusarium , Polyporales , Thymelaeaceae , Odorantes , Thymelaeaceae/microbiología
10.
Mini Rev Med Chem ; 22(22): 2813-2819, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35319363

RESUMEN

Due to their difficulty in pathogenesis, nervous system disease (NSD) therapies have long been challenging problems for researchers. With the rise in the ageing population, the quest for successful NSD therapies has become a hot topic. Polysaccharides demonstrated numerous biological effects in anti-oxidation, anti-inflammation, and immune regulation. In recent years, several studies have been conducted in light of the connection between the properties of polysaccharides and the pathogenesis of neurological conditions. In this review, we aim to discuss the most recent reports on the beneficial properties and mechanisms of polysaccharides for nervous system-related diseases.


Asunto(s)
Enfermedades del Sistema Nervioso , Humanos , Enfermedades del Sistema Nervioso/tratamiento farmacológico , Enfermedades del Sistema Nervioso/patología , Envejecimiento , Polisacáridos/farmacología , Polisacáridos/uso terapéutico
11.
Curr Mol Pharmacol ; 15(6): 803-814, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35023463

RESUMEN

COVID-19, which is speedily distributed across the world and presents a significant challenge to public health, is caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Following MERS coronavirus (MERS-CoV) and SARS, this is the third severe coronavirus outbreak in less than 20 years. To date, there are no exact agents and vaccines available for the treatment of COVID-19 that are clinically successful. Antimicrobial medications are effective in controlling infectious diseases. However, the extensive use of antibiotics makes microbes more resistant to drugs and demands novel bioactive agents' development. Polysaccharides are currently commonly used in the biomedical and pharmaceutical industries for their remarkable applications. Polysaccharides appear to have a wide range of anti-virus (anti-coronavirus) and antimicrobial applications. Polysaccharides are able to induce bacterial cell membrane disruption as they demonstrate potency in binding onto the surfaces of microbial cells. Here, the antiviral mechanisms of such polysaccharides and their success in the application of antiviral infections are reviewed. Additionally, this report provides a summary of current advancements of well-recognized polysaccharides as antimicrobial and anti-biofilm agents.


Asunto(s)
Tratamiento Farmacológico de COVID-19 , Virus , Antivirales/farmacología , Antivirales/uso terapéutico , Humanos , Polisacáridos/farmacología , Polisacáridos/uso terapéutico , SARS-CoV-2
12.
Bioorg Chem ; 104: 104277, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-32971414

RESUMEN

A series of aminated- (1-9) and sulfonamide-containing diarylpentadienones (10-18) were synthesized, structurally characterized, and evaluated for their in vitro anti-diabetic potential on α-glucosidase and DPP-4 enzymes. It was found that all the new molecules were non-associated PAINS compounds. The sulfonamide-containing series (compounds 10-18) selectively inhibited α-glucosidase over DPP-4, in which compound 18 demonstrated the highest activity with an IC50 value of 5.69 ± 0.5 µM through a competitive inhibition mechanism. Structure-activity relationship (SAR) studies concluded that the introduction of the trifluoromethylbenzene sulfonamide moiety was essential for the suppression of α-glucosidase. The most active compound 18, was then further tested for in vivo toxicities using the zebrafish animal model, with no toxic effects detected in the normal embryonic development, blood vessel formation, and apoptosis of zebrafish. Docking simulation studies were also carried out to better understand the binding interactions of compound 18 towards the homology modeled α -glucosidase and the human lysosomal α -glucosidase enzymes. The overall results suggest that the new sulfonamide-containing diarylpentadienones, compound 18, could be a promising candidate in the search for a new α-glucosidase inhibitor, and can serve as a basis for further studies involving hit-to-lead optimization, in vivo efficacy and safety assessment in an animal model and mechanism of action for the treatment of T2DM patients.


Asunto(s)
Alcadienos/farmacología , Desarrollo de Medicamentos , Inhibidores de Glicósido Hidrolasas/farmacología , Simulación del Acoplamiento Molecular , alfa-Glucosidasas/metabolismo , Alcadienos/síntesis química , Alcadienos/química , Animales , Relación Dosis-Respuesta a Droga , Inhibidores de Glicósido Hidrolasas/síntesis química , Inhibidores de Glicósido Hidrolasas/química , Humanos , Estructura Molecular , Relación Estructura-Actividad , Sulfonamidas/química , Sulfonamidas/farmacología , Pez Cebra/embriología
13.
J Mol Model ; 26(6): 142, 2020 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-32417971

RESUMEN

Fruit bromelain is a cysteine protease accumulated in pineapple fruits. This proteolytic enzyme has received high demand for industrial and therapeutic applications. In this study, fruit bromelain sequences QIM61759, QIM61760 and QIM61761 were retrieved from the National Center for Biotechnology Information (NCBI) Genbank Database. The tertiary structure of fruit bromelain QIM61759, QIM61760 and QIM61761 was generated by using MODELLER. The result revealed that the local stereochemical quality of the generated models was improved by using multiple templates during modelling process. Moreover, by comparing with the available papain model, structural analysis provides an insight on how pro-peptide functions as a scaffold in fruit bromelain folding and contributing to inactivation of mature protein. The structural analysis also disclosed the similarities and differences between these models. Lastly, thermal stability of fruit bromelain was studied. Molecular dynamics simulation of fruit bromelain structures at several selected temperatures demonstrated how fruit bromelain responds to elevation of temperature.


Asunto(s)
Ananas/enzimología , Bromelaínas/metabolismo , Simulación de Dinámica Molecular , Bromelaínas/química , Estabilidad de Enzimas , Calor , Conformación Proteica
14.
Food Chem ; 266: 183-191, 2018 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-30381175

RESUMEN

Cysteine proteases in pineapple (Ananas comosus) plants are phytotherapeutical agents that demonstrate anti-edematous, anti-inflammatory, anti-thrombotic and fibrinolytic activities. Bromelain has been identified as an active component and as a major protease of A. comosus. Bromelain has gained wide acceptance and compliance as a phytotherapeutical drug. The proteolytic fraction of pineapple stem is termed stem bromelain, while the one presents in the fruit is known as fruit bromelain. The amino acid sequence and domain analysis of the fruit and stem bromelains demonstrated several differences and similarities of these cysteine protease family members. In addition, analysis of the modelled fruit (BAA21848) and stem (CAA08861) bromelains revealed the presence of unique properties of the predicted structures. Sequence analysis and structural prediction of stem and fruit bromelains of A. comosus along with the comparison of both structures provides a new insight on their distinct properties for industrial application.


Asunto(s)
Ananas/enzimología , Bromelaínas/química , Modelos Moleculares , Secuencia de Aminoácidos , Bromelaínas/metabolismo , Conformación Proteica , Análisis de Secuencia de Proteína
15.
Food Chem ; 265: 253-259, 2018 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-29884381

RESUMEN

Eleven compounds were identified during profiling of polyphenols by UPLC-QTOF/MS. In abundance was quercetin-3-O-α-l-arabinofuranoside in M. malabathricum ethanolic leaves extract while 6-hydroxykaempferol-3-O-glucoside was present in the leaves extract of M. decenfidum (its rare variety). TPC and TFC were significantly higher in M. decemfidum extract than M. malabathricum extract. During DPPH, FRAF and ß-carotene bleaching assays, M. decemfidum extract exhibited greater antioxidant activity compared to M. malabathricum extract. Effect of M. malabathricum and M. decemfidum extracts on viability of MDA-MB-231 cell at concentrations 6.25-100 µg/mL were evaluated for 24, 48 and 72 h. After 48 and 72 h treatment, M. malabathricum and M. decemfidum leaves extracts exhibited significant activity in inhibiting MDA-MB-231 cancer cell line with M. malabathricum extract being more cytotoxic. M. malabathricum and M. imbricatum serves as potential daily dietary source of natural phenolics and to improve chemotherapeutic effectiveness.


Asunto(s)
Antioxidantes/química , Cromatografía Líquida de Alta Presión , Melastomataceae/química , Fenoles/análisis , Espectrometría de Masa por Ionización de Electrospray , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/patología , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Femenino , Humanos , Melastomataceae/metabolismo , Fenoles/farmacología , Extractos Vegetales/química , Extractos Vegetales/farmacología , Hojas de la Planta/química , Hojas de la Planta/metabolismo
16.
J Sci Food Agric ; 97(5): 1386-1395, 2017 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-27790704

RESUMEN

Bromelain is a mixture of proteolytic enzymes found in pineapple (Ananas comosus) plants. It can be found in several parts of the pineapple plant, including the stem, fruit, leaves and peel. High demand for bromelain has resulted in gradual increases in bromelain production. These increases have led to the need for a bromelain production strategy that yields more purified bromelain at a lower cost and with fewer production steps. Previously, bromelain was purified by conventional centrifugation, ultrafiltration and lyophilisation. Recently, the development of more modern purification techniques such as gel filtration, ion exchange chromatography, affinity chromatography, aqueous two-phase extraction and reverse micelle chromatography has resulted in increased industrial bromelain production worldwide. In addition, recombinant DNA technology has emerged as an alternative strategy for producing large amounts of ultrapure bromelain. An up-to-date compilation of data regarding the commercialisation of bromelain in the clinical, pharmaceutical and industrial fields is provided in this review. © 2016 Society of Chemical Industry.


Asunto(s)
Bromelaínas/aislamiento & purificación , Tecnología de Alimentos/métodos , Ananas/química , Ananas/enzimología , Biotecnología/métodos , Bromelaínas/química , ADN Recombinante
17.
Gene ; 545(2): 253-61, 2014 Jul 25.
Artículo en Inglés | MEDLINE | ID: mdl-24811681

RESUMEN

Bacillus lehensis G1 is a Gram-positive, moderately alkalitolerant bacterium isolated from soil samples. B. lehensis produces cyclodextrin glucanotransferase (CGTase), an enzyme that has enabled the extensive use of cyclodextrin in foodstuffs, chemicals, and pharmaceuticals. The genome sequence of B. lehensis G1 consists of a single circular 3.99 Mb chromosome containing 4017 protein-coding sequences (CDSs), of which 2818 (70.15%) have assigned biological roles, 936 (23.30%) have conserved domains with unknown functions, and 263 (6.55%) have no match with any protein database. Bacillus clausii KSM-K16 was established as the closest relative to B. lehensis G1 based on gene content similarity and 16S rRNA phylogenetic analysis. A total of 2820 proteins from B. lehensis G1 were found to have orthologues in B. clausii, including sodium-proton antiporters, transport proteins, and proteins involved in ATP synthesis. A comparative analysis of these proteins and those in B. clausii and other alkaliphilic Bacillus species was carried out to investigate their contributions towards the alkalitolerance of the microorganism. The similarities and differences in alkalitolerance-related genes among alkalitolerant/alkaliphilic Bacillus species highlight the complex mechanism of pH homeostasis. The B. lehensis G1 genome was also mined for proteins and enzymes with potential viability for industrial and commercial purposes.


Asunto(s)
Bacillus/genética , Genoma Bacteriano , Genómica , Microbiología del Suelo , Transportadoras de Casetes de Unión a ATP/genética , Transportadoras de Casetes de Unión a ATP/metabolismo , Adaptación Biológica/genética , Secuencia de Aminoácidos , Antiportadores/genética , Antiportadores/metabolismo , Bacillus/crecimiento & desarrollo , Bacillus/metabolismo , Composición de Base , Pared Celular/química , Pared Celular/metabolismo , Complejo IV de Transporte de Electrones/química , Complejo IV de Transporte de Electrones/genética , Complejo IV de Transporte de Electrones/metabolismo , Tamaño del Genoma , Concentración de Iones de Hidrógeno , Datos de Secuencia Molecular , Sistemas de Lectura Abierta , Alineación de Secuencia , Suelo/química
18.
J Comput Aided Mol Des ; 28(6): 685-98, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24849507

RESUMEN

The structure of a novel psychrophilic ß-mannanase enzyme from Glaciozyma antarctica PI12 yeast has been modelled and analysed in detail. To our knowledge, this is the first attempt to model a psychrophilic ß-mannanase from yeast. To this end, a 3D structure of the enzyme was first predicted using a threading method because of the low sequence identity (<30%) using MODELLER9v12 and simulated using GROMACS at varying low temperatures for structure refinement. Comparisons with mesophilic and thermophilic mannanases revealed that the psychrophilic mannanase contains longer loops and shorter helices, increases in the number of aromatic and hydrophobic residues, reductions in the number of hydrogen bonds and salt bridges and numerous amino acid substitutions on the surface that increased the flexibility and its efficiency for catalytic reactions at low temperatures.


Asunto(s)
Basidiomycota/enzimología , beta-Manosidasa/química , Aclimatación , Secuencia de Aminoácidos , Basidiomycota/química , Basidiomycota/fisiología , Frío , Simulación de Dinámica Molecular , Datos de Secuencia Molecular , Conformación Proteica , Alineación de Secuencia , beta-Manosidasa/metabolismo
19.
J Mol Model ; 19(8): 3369-83, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23686283

RESUMEN

A novel α-amylase was isolated successfully from Glaciozyma antarctica PI12 using DNA walking and reverse transcription-polymerase chain reaction (RT-PCR) methods. The structure of this psychrophilic α-amylase (AmyPI12) from G. antarctica PI12 has yet to be studied in detail. A 3D model of AmyPI12 was built using a homology modelling approach to search for a suitable template and to generate an optimum target-template alignment, followed by model building using MODELLER9.9. Analysis of the AmyPI12 model revealed the presence of binding sites for a conserved calcium ion (CaI), non-conserved calcium ions (CaII and CaIII) and a sodium ion (Na). Compared with its template-the thermostable α-amylase from Bacillus stearothermophilus (BSTA)-the binding of CaII, CaIII and Na ions in AmyPI12 was observed to be looser, which suggests that the low stability of AmyPI12 allows the protein to work at different temperature scales. The AmyPI12 amino acid sequence and model were compared with thermophilic α-amylases from Bacillus species that provided the highest structural similarities with AmyPI12. These comparative studies will enable identification of possible determinants of cold adaptation.


Asunto(s)
Adaptación Fisiológica , Proteínas Bacterianas/química , Basidiomycota/química , Proteínas Fúngicas/química , Geobacillus stearothermophilus/química , alfa-Amilasas/química , Secuencia de Aminoácidos , Regiones Antárticas , Proteínas Bacterianas/clasificación , Proteínas Bacterianas/genética , Basidiomycota/enzimología , Basidiomycota/genética , Calcio/química , Cationes , Frío , Proteínas Fúngicas/clasificación , Proteínas Fúngicas/genética , Geobacillus stearothermophilus/enzimología , Geobacillus stearothermophilus/genética , Calor , Modelos Moleculares , Datos de Secuencia Molecular , Filogenia , Unión Proteica , Estructura Terciaria de Proteína , Alineación de Secuencia , Sodio/química , Homología Estructural de Proteína , alfa-Amilasas/clasificación , alfa-Amilasas/genética
20.
J Comput Aided Mol Des ; 26(8): 947-61, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22710891

RESUMEN

The structure of psychrophilic chitinase (CHI II) from Glaciozyma antarctica PI12 has yet to be studied in detail. Due to its low sequence identity (<30 %), the structural prediction of CHI II is a challenge. A 3D model of CHI II was built by first using a threading approach to search for a suitable template and to generate an optimum target-template alignment, followed by model building using MODELLER9v7. Analysis of the catalytic insertion domain structure in CHI II revealed an increase in the number of aromatic residues and longer loops compared to mesophilic and thermophilic chitinases. A molecular dynamics simulation was used to examine the stability of the CHI II structure at 273, 288 and 300 K. Structural analysis of the substrate-binding cleft revealed a few exposed aromatic residues. Substitutions of certain amino acids in the surface and loop regions of CHI II conferred an increased flexibility to the enzyme, allowing for an adaptation to cold temperatures. A substrate binding comparison of CHI II with the mesophilic chitinase from Coccidioides immitis, 1D2K, suggested that the psychrophilic adaptation and catalytic activity at low temperatures were achieved through a reduction in the number of salt bridges, fewer hydrogen bonds and an increase in the exposure of the hydrophobic side chains to the solvent.


Asunto(s)
Adaptación Fisiológica , Basidiomycota/enzimología , Quitinasas/química , Simulación de Dinámica Molecular , Secuencia de Aminoácidos , Dominio Catalítico , Frío , Enlace de Hidrógeno , Conformación Molecular , Datos de Secuencia Molecular
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