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1.
Nucleic Acids Res ; 48(5): 2209-2219, 2020 03 18.
Artigo em Inglês | MEDLINE | ID: mdl-31943056

RESUMO

Ongoing large-scale genome sequencing projects are forecasting a data deluge that will almost certainly overwhelm current analytical capabilities of evolutionary genomics. In contrast to population genomics, there are no standardized methods in evolutionary genomics for extracting evolutionary and functional (e.g. gene-trait association) signal from genomic data. Here, we examine how current practices of multi-species comparative genomics perform in this aspect and point out that many genomic datasets are under-utilized due to the lack of powerful methodologies. As a result, many current analyses emphasize gene families for which some functional data is already available, resulting in a growing gap between functionally well-characterized genes/organisms and the universe of unknowns. This leaves unknown genes on the 'dark side' of genomes, a problem that will not be mitigated by sequencing more and more genomes, unless we develop tools to infer functional hypotheses for unknown genes in a systematic manner. We provide an inventory of recently developed methods capable of predicting gene-gene and gene-trait associations based on comparative data, then argue that realizing the full potential of whole genome datasets requires the integration of phylogenetic comparative methods into genomics, a rich but underutilized toolbox for looking into the past.


Assuntos
Biologia Computacional/métodos , Epistasia Genética , Genoma , Família Multigênica , Filogenia , Animais , Celulase/classificação , Celulase/genética , Celulase/metabolismo , Sistema Enzimático do Citocromo P-450/classificação , Sistema Enzimático do Citocromo P-450/genética , Sistema Enzimático do Citocromo P-450/metabolismo , Bases de Dados Genéticas , Conjuntos de Dados como Assunto , Dictyostelium/enzimologia , Dictyostelium/genética , Fungos/classificação , Fungos/enzimologia , Fungos/genética , Dosagem de Genes , Loci Gênicos , Sequenciamento de Nucleotídeos em Larga Escala/estatística & dados numéricos , Phascolarctidae/genética , Phascolarctidae/metabolismo , Plantas/classificação , Plantas/genética , Plantas/metabolismo
2.
Chemosphere ; 242: 125163, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31677518

RESUMO

The use of fungicides bears the risk of many undesirable outcomes that are manifested in, among other things, changes in the structure and activity of microorganisms. This study aimed at determining the effect of a Helicur 250 EW preparation, used to protect crops against fungal diseases, on the microbiological and biochemical activity of soil and on the development of Horderum vulgare L. The fungicide was sprayed on leaves of spring barley in the following doses (per active substance, i.e. tebuconazole, TEB): 0.046, 0.093, 0.139, 1.395, and 2.790 mg TEB plant-1. The following indices were analyzed in the study: index of microorganisms resistance (RS) to the effects of fungicide, microorganisms colony development index (CD), microorganisms ecophysiological diversity index (EP), genetic diversity of bacteria, enzymatic activity, and effect of the fungicide on spring barley development (IFH). The most susceptible to the effects of the fungicide turned out to be fungi. The metagenomic analysis demonstrated that the bacterial community differed in terms of structure and percentage contribution in the soil exposed to the fungicide from the control soil even at the Phylum level. However, Proteobacteria appeared to be the prevailing taxon in both soils. Bacillus arabhattai, B. soli, and B. simplex occurred exclusively in the control soil, whereas Ramlibacter tataounensis, Azospirillum palatum, and Kaistobacter terrae - exclusively in the soil contaminated with the fungicide. Helicur 250 EW suppressed activities of all soil enzymes except for arylsulfatase. In addition, it proved to be a strong inhibitor of spring barley growth and development.


Assuntos
Fungicidas Industriais/toxicidade , Hordeum/crescimento & desenvolvimento , Microbiota/efeitos dos fármacos , Microbiologia do Solo/normas , Poluentes do Solo/toxicidade , Triazóis/toxicidade , Bactérias/efeitos dos fármacos , Bactérias/enzimologia , Fungos/efeitos dos fármacos , Fungos/enzimologia , Fungicidas Industriais/análise , Metagenoma/efeitos dos fármacos , Microbiota/genética , Folhas de Planta/crescimento & desenvolvimento , Solo/química , Poluentes do Solo/análise , Triazóis/análise
3.
Enzyme Microb Technol ; 133: 109467, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31874689

RESUMO

The specific activity and enantioselectivity of immobilized cutinases from Aspergillus oryzae (AoC) and Humicola insolens (HiC) were compared with those of lipases from Thermomyces lanuginosus (TLL), Rhizomucor miehei (RML) and Lipase B from Candida antarctica (CALB) for menthol and its analogs that include isopulegol, trans-2-tert-butylcyclohexanol (2TBC), and dihydrocarveol (DHC). Common features of these alcohols are two bulky substituents: a cyclohexyl ring and an alkyl substituent. Dissimilarities are that the alkyl group reside at different positions or have dissimilar structures. The aim was to develop an understanding at a molecular level of similarities and differences in the catalytic behavior of the selected cutinases and lipases as a function of substrate structural elements. The experimental results reflect the (-)-enantioselectivity for AoC, HiC, TLL, and RML, while CALB is only active on DHC with (+)-enantioselectivity. In most cases, AoC has the highest activity while HiC is significantly more active than other enzymes on 2TBC. The E values of AoC, HiC, TLL, and RML for menthol are 27.8, 16.5, 155, and 125, respectively. HiC has a higher activity (>10-fold) on (-)-2TBC than AoC while they exhibit similar activities on menthol. Docking results reveal that the bulky group adjacent to the hydroxyl group determines the enantioselectivity of AoC, HiC, TLL, and RML. Amino acid residues that dominate the enantioselectivity of these enzymes are AoC's Phe195 aromatic ring; HiC's hydrophobic Leu 174 and Ile 169 groups; TLL's ring structures of Trp89, His258 and Tyr21; and Trp88 for RML. Results of this study highlight that cutinases can provide important advantages relative to lipases for enantioselective transformation, most notably with bulky and sterically hindered substrates.


Assuntos
Hidrolases de Éster Carboxílico/metabolismo , Enzimas Imobilizadas/metabolismo , Proteínas Fúngicas/metabolismo , Lipase/metabolismo , Mentol/análogos & derivados , Catálise , Fungos/enzimologia , Interações Hidrofóbicas e Hidrofílicas , Cinética , Simulação de Acoplamento Molecular
4.
J Enzyme Inhib Med Chem ; 35(1): 59-64, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31663383

RESUMO

A primary strategy to combat antimicrobial resistance is the identification of novel therapeutic targets and anti-infectives with alternative mechanisms of action. The inhibition of the metalloenzymes carbonic anhydrases (CAs, EC 4.2.1.1) from pathogens (bacteria, fungi, and protozoa) was shown to produce an impairment of the microorganism growth and virulence. As phosphonamidates have been recently validated as human α-CA inhibitors (CAIs) and no phosphorus-based zinc-binding group have been assessed to date against ß-class CAs, herein we report an inhibition study with this class of compounds against ß-CAs from pathogenic bacteria, fungi, and protozoa. Our data suggest that phosphonamidates are among the CAIs with the best selectivity for ß-class over human isozymes, making them interesting leads for the development of new anti-infectives.


Assuntos
Amidas/farmacologia , Anti-Infecciosos/farmacologia , Inibidores da Anidrase Carbônica/farmacologia , Anidrases Carbônicas/metabolismo , Compostos Organometálicos/farmacologia , Ácidos Fosfóricos/farmacologia , Amidas/química , Anti-Infecciosos/síntese química , Anti-Infecciosos/química , Bactérias/efeitos dos fármacos , Bactérias/enzimologia , Inibidores da Anidrase Carbônica/síntese química , Inibidores da Anidrase Carbônica/química , Relação Dose-Resposta a Droga , Fungos/efeitos dos fármacos , Fungos/enzimologia , Humanos , Leishmania donovani/efeitos dos fármacos , Leishmania donovani/enzimologia , Estrutura Molecular , Compostos Organometálicos/síntese química , Compostos Organometálicos/química , Ácidos Fosfóricos/química , Fósforo/química , Fósforo/farmacologia , Relação Estrutura-Atividade , Zinco/química , Zinco/farmacologia
5.
Int J Mol Sci ; 20(19)2019 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-31623309

RESUMO

Amylases are probably the best studied glycoside hydrolases and have a huge biotechnological value for industrial processes on starch. Multiple amylases from fungi and microbes are currently in use. Whereas bacterial amylases are well suited for many industrial processes due to their high stability, fungal amylases are recognized as safe and are preferred in the food industry, although they lack the pH tolerance and stability of their bacterial counterparts. Here, we describe three amylases, two of which have a broad pH spectrum extending to pH 8 and higher stability well suited for a broad set of industrial applications. These enzymes have the characteristic GH13 α-amylase fold with a central (ß/α)8-domain, an insertion domain with the canonical calcium binding site and a C-terminal ß-sandwich domain. The active site was identified based on the binding of the inhibitor acarbose in form of a transglycosylation product, in the amylases from Thamnidium elegans and Cordyceps farinosa. The three amylases have shortened loops flanking the nonreducing end of the substrate binding cleft, creating a more open crevice. Moreover, a potential novel binding site in the C-terminal domain of the Cordyceps enzyme was identified, which might be part of a starch interaction site. In addition, Cordyceps farinosa amylase presented a successful example of using the microseed matrix screening technique to significantly speed-up crystallization.


Assuntos
Amilases/química , Amilases/metabolismo , Fungos/enzimologia , Sítios de Ligação , Domínio Catalítico , Ativação Enzimática , Estabilidade Enzimática , Glucose/química , Glucose/metabolismo , Glicosilação , Concentração de Íons de Hidrogênio , Modelos Moleculares , Conformação Molecular , Ligação Proteica , Relação Estrutura-Atividade , alfa-Amilases/química , alfa-Amilases/metabolismo
6.
Artigo em Inglês | MEDLINE | ID: mdl-31564305

RESUMO

Non-heme iron enzymes catalyze a wide range of chemical transformations, serving as one of the key types of tailoring enzymes in the biosynthesis of natural products. Hydroxylation reaction is the most common type of reactions catalyzed by these enzymes and hydroxylation reactions have been extensively investigated mechanistically. However, the mechanistic details for other types of transformations remain largely unknown or unexplored. In this paper, we present some of the most recently discovered transformations, including endoperoxidation, orthoester formation, cyclopropanation, oxidative C-C and C-S bond formation reactions. In addition, many of them are multi-functional enzymes, which further complicate their mechanistic investigations. In this work, we summarize their biosynthetic pathways, with special emphasis on the mechanistic details available for these newly discovered enzymes.


Assuntos
Produtos Biológicos/metabolismo , Fungos/enzimologia , Ferroproteínas não Heme/metabolismo , Produtos Biológicos/química , Proteínas Fúngicas , Modelos Moleculares , Ferroproteínas não Heme/química , Conformação Proteica
7.
Enzyme Microb Technol ; 131: 109396, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31615679

RESUMO

Endophytic fungi provide benefits to host plants by producing a diverse class of secondary metabolites (natural products). Arrays of polyketide natural products are synthesized by specific classes of polyketide synthases (PKS I, II and III) in host organisms. In the present study, we attempt to screen and identify type III PKSs in culturable fungal endophytes isolated from the ethno medicinal plants including Arbus precatorius, Bacopa monnieri,Citrus aurantifolia and Datura metel to detect the genetic potential of endophytic fungi in producing bioactive compounds. A total of seventeen endophytic fungal strains belonging to eight genera were identified using fungal morphology and rDNA-ITS phylogenetic analyses. A CODEHOP-PCR based strategy was followed to design degenerate primers for the screening of type III PKS genes from fungal endophytes. We had successfully amplified partial PKS genes from eight endophytes. The amplified PKS sequences showed 60-99% identity to already characterized/putative PKS genes. From the partial sequence of FiPKS from Fusarium incarnatum BMER1, a full-length gene was amplified, cloned and characterized. FiPKScDNA was cloned and expressed in E. coli Lemo21 (DE3) and the purified protein was shown to produce pyrones and resorcinols using acyl-CoA thioesters as substrates. FiPKS showed the highest catalytic efficiency of 7.6 × 104 s-1 M-1 with stearoyl CoA as a starter unit. This study reports the identification and characterization of type III PKS from endophytes of medicinal plants by CODEHOP PCR.


Assuntos
Aciltransferases/genética , Endófitos/enzimologia , Fungos/enzimologia , Plantas Medicinais/microbiologia , Clonagem Molecular , Escherichia coli/genética , Escherichia coli/metabolismo , Fungos/classificação , Fungos/genética , Fungos/isolamento & purificação , Expressão Gênica , Cinética , Técnicas Microbiológicas , Filogenia , Pironas/metabolismo , Resorcinóis/metabolismo , Análise de Sequência de DNA , Homologia de Sequência
8.
World J Microbiol Biotechnol ; 35(9): 144, 2019 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-31493195

RESUMO

Chitinases are a group of hydrolytic enzymes that catalyze chitin, nd are synthesized by a wide variety of organisms. In nature, microbial chitinases are primarily responsible for chitin decomposition. Several chitinases have been reported and characterized, and they are garnering increasing attention for their uses in a wide range of applications. In the food industry, the direct fermentation of seafood, such as crab and shrimp shells, using chitinolytic microorganisms has contributed to increased nutritional benefits through the enhancement of chitin degradation into chitooligosaccharides. These compounds have been demonstrated to improve human health through their antitumor, antimicrobial, immunomodulatory, antioxidant, and anti-inflammatory properties. Moreover, chitinase and chitinous materials are used in the food industry for other purposes, such as the production of single-cell proteins, chitooligosaccharides, N-acetyl D-glucosamines, biocontrol, functional foods, and various medicines. The functional properties and hydrolyzed products of chitinase, however, depend upon its source and physicochemical characteristics. The present review strives to clarify these perspectives and critically discusses the advances and limitations of microbial chitinase in the further production of functional foods.


Assuntos
Biotecnologia , Quitinases/biossíntese , Alimento Funcional , Anti-Inflamatórios , Antineoplásicos , Antioxidantes , Antivirais , Bactérias/enzimologia , Agentes de Controle Biológico , Quitina/análogos & derivados , Quitina/metabolismo , Proteínas na Dieta , Fermentação , Indústria Alimentícia , Fungos/enzimologia , Glucosamina/análogos & derivados , Hidrólise , Fatores Imunológicos , Medicina , Alimentos Marinhos
9.
J Enzyme Inhib Med Chem ; 34(1): 1652-1659, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31530034

RESUMO

Eight genetically distinct carbonic anhydrase (EC 4.2.1.1) enzyme families (α-, ß-, γ- δ-, ζ-, η-, θ- and ι-CAs) were described to date. On the other hand, 16 mammalian α-CA isoforms are known to be involved in many diseases such as glaucoma, edema, epilepsy, obesity, hypoxic tumors, neuropathic pain, arthritis, neurodegeneration, etc. Although CA inhibitors were investigated for the management of a variety of such disorders, the activators just started to be investigated in detail for their in vivo effects. This review summarizes the activation profiles of α-, ß, γ-, δ-, ζ- and η- CAs from various organisms (animals, fungi, protozoan, bacteria and archaea) with the most investigated classes of activators, the amines and the amino acids.


Assuntos
Aminas/farmacologia , Aminoácidos/farmacologia , Inibidores da Anidrase Carbônica/farmacologia , Anidrases Carbônicas/metabolismo , Aminas/síntese química , Aminas/química , Aminoácidos/síntese química , Aminoácidos/química , Bactérias/enzimologia , Inibidores da Anidrase Carbônica/síntese química , Inibidores da Anidrase Carbônica/química , Entamoeba histolytica/enzimologia , Fungos/enzimologia , Isoenzimas/antagonistas & inibidores , Isoenzimas/metabolismo , Estrutura Molecular
10.
Yi Chuan ; 41(8): 736-745, 2019 Aug 20.
Artigo em Chinês | MEDLINE | ID: mdl-31447424

RESUMO

As one of plant cell wall components, pectin is the main anti-nutritional factor in livestock and poultry feeds and has an adverse effect on utilization efficiency of feed energy and nitrogen. Pectinases, which are widely found in microorganisms such as bacteria, yeast and filamentous fungi in nature,can improve feed efficiency by relieving the anti-nutritional effect of pectin through promoting the hydrolysis reaction of feed pectin. To explore the feasibility of expressing microbial-derived pectinase genes in pig cells, we introduced microbial-derived pectinase genes pg5a, pgI, pga3A, and pgaA into porcine PK 15 cells by lipofection for heterogenous expression. Enzymatic activities of the pectinases encoded by these genes were analyzed using the 3,5 dinitrosalicylic acid (DNS) method. Results showed that all four pectinase genes were able to be transcribed into mRNAs in porcine PK 15 cells, but only pg5a and pgI were adapted to the porcine cell expression system. Among them, the maximum activity of pectinase PG5A was 0.95 U/mL, the optimum pH was pH 4.0, and the enzymatic activity was maintained above 46% in the range of pH 4.6 to 6.0. Pectinase PGI obtained the highest enzymatic activity at pH 5.0, which was 0.30 U/mL, and maintained more than 35% of the activity in the range of pH 4.0 to 6.0. The results of digestive protease tolerance test showed that PG5A and PGI were highly resistant to pepsin and trypsin. After treatment with 1 mg/mL pig pepsin for two hours, the residual enzymatic activities of PG5A and PGI were 76% and 71%, respectively. And after two hours treatment with 1 mg/mL of pig trypsin, the remaining enzymatic activities of PG5A and PGI were 44% and 93%, respectively. In summary, pectinase PG5A and PGI can be effectively expressed in pig cells, and have strong tolerance to pig intestinal pH environment and digestive proteases. Therefore, both pg5a and pgI can be used as candidate genes for production of transgenic pigs.


Assuntos
Bactérias/enzimologia , Fungos/enzimologia , Poligalacturonase/biossíntese , Animais , Células Cultivadas , Pectinas , Poligalacturonase/genética , Suínos
11.
Appl Microbiol Biotechnol ; 103(19): 7891-7902, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31401753

RESUMO

Functional carbohydrates are ideal substitutes for table sugar and make up a large share of the worldwide functional food market because of their numerous physiological benefits. Growing attention has been focused on levan, a ß-(2,6) fructan that possesses more favorable physicochemical properties, such as lower intrinsic viscosity and greater colloidal stability, than ß-(2,1) inulin. Levan can be used not only as a functional carbohydrate but also as feedstock for the production of levan-type fructooligosaccharides (L-FOSs). Three types of levan-degrading enzymes (LDEs), including levanase (EC 3.2.1.65), ß-(2,6)-fructan 6-levanbiohydrolase (LF2ase, EC 3.2.1.64), and levan fructotransferase (LFTase, EC 4.2.2.16), play significant roles in the biological production of L-FOSs. These three enzymes convert levan into different L-FOSs, levanbiose, and difructose anhydride IV (DFA IV), respectively. The prebiotic properties of both L-FOSs and DFA IV have been confirmed in recent years. Although levanase, LF2ase, and LFTase belong to the same O-glycoside hydrolase 32 family (GH32), their catalytic properties and product spectra differ significantly. In this paper, recent studies on these LDEs are reviewed, including those investigating microbial source and catalytic properties. Additionally, comparisons of LDEs, including those of their differing cleavage behavior and applications for different L-FOSs, are presented in detail.


Assuntos
Bactérias/enzimologia , Frutanos/metabolismo , Fungos/enzimologia , Glicosídeo Hidrolases/metabolismo , Hexosiltransferases/metabolismo , Oligossacarídeos/metabolismo , Biotransformação
12.
Appl Microbiol Biotechnol ; 103(17): 6885-6902, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31309267

RESUMO

The secretome, the complement of extracellular proteins, is a reflection of the interaction of an organism with its host or substrate, thus a determining factor for the organism's fitness and competitiveness. Hence, the secretome impacts speciation and organismal evolution. The zoosporic Chytridiomycota, Blastocladiomycota, Neocallimastigomycota, and Cryptomycota represent the earliest diverging lineages of the Fungal Kingdom. The review describes the enzyme compositions of these zoosporic fungi, underscoring the enzymes involved in biomass degradation. The review connects the lifestyle and substrate affinities of the zoosporic fungi to the secretome composition by examining both classical phenotypic investigations and molecular/genomic-based studies. The carbohydrate-active enzyme profiles of 19 genome-sequenced species are summarized. Emphasis is given to recent advances in understanding the functional role of rumen fungi, the basis for the devastating chytridiomycosis, and the structure of fungal cellulosome. The approach taken by the review enables comparison of the secretome enzyme composition of anaerobic versus aerobic early-diverging fungi and comparison of enzyme portfolio of specialized parasites, pathogens, and saprotrophs. Early-diverging fungi digest most major types of biopolymers: cellulose, hemicellulose, pectin, chitin, and keratin. It is thus to be expected that early-diverging fungi in its entirety represents a rich and diverse pool of secreted, metabolic enzymes. The review presents the methods used for enzyme discovery, the diversity of enzymes found, the status and outlook for recombinant production, and the potential for applications. Comparative studies on the composition of secretome enzymes of early-diverging fungi would contribute to unraveling the basal lineages of fungi.


Assuntos
Celulossomas/enzimologia , Proteínas Fúngicas/metabolismo , Fungos/classificação , Fungos/enzimologia , Animais , Evolução Biológica , Biopolímeros/metabolismo , Celulossomas/genética , Celulossomas/metabolismo , Proteínas Fúngicas/genética , Fungos/genética , Fungos/metabolismo , Genoma Fúngico/genética , Filogenia , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Rúmen/microbiologia
13.
J Sci Food Agric ; 99(14): 6522-6534, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31321764

RESUMO

BACKGROUND: Dajiang is fermented based on the metabolism of microbial communities in bean sauce mash, a traditional fermented soybean product in China. The current study first investigated the metaproteome of bean sauce mash. This was followed by an analysis of its biological functions and its microbial community to reveal information about strains and about the expressed proteins to better understand the roles of the microbiota in bean sauce mash. RESULTS: The metaproteomic results demonstrated that a total of 1415 microbial protein clusters were expressed mainly by members of the Penicillium and Rhizopus genera and were classified into 100 cellular components, 238 biological processes, and 220 molecular function categories by gene ontology (GO) annotation. Enzymes associated with glycolysis metabolic pathways were also identified. These can provide the energy required for microbial fermentation. Illumina MiSeq sequencing technology results showed that the microorganism communities of bean sauce mash exhibited a high level of diversity. Microbiological analysis demonstrated that the Penicillium, Mucor, Fusarium, Aspergillus, and Rhizopus fungi, and Lactobacillus, Enterococcus, Fructobacillus, Staphylococcus, Carnobacterium genera were predominant 22 samples. CONCLUSION: The profiles and insights in the current study are important for research on bean sauce mash and related products in terms of their food microbial ecology. The information obtained from this study will help the development of stable sufu starter cultures with unique sensory qualities. © 2019 Society of Chemical Industry.


Assuntos
Bactérias/enzimologia , Fungos/enzimologia , Microbiota , Soja/microbiologia , Bactérias/classificação , Bactérias/genética , Bactérias/isolamento & purificação , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , China , Fermentação , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Fungos/classificação , Fungos/genética , Fungos/isolamento & purificação , Soja/metabolismo
14.
J Biosci ; 44(2)2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31180060

RESUMO

Pyruvate carboxylase (Pyc) catalyzes formation of oxaloacetic acid from pyruvic acid by fixing one mole of CO2. Many evidences have confirmed that biosynthesis of some different kinds of organic acids and intracellular and extracellular lipids is driven by Pyc and over-expression of the PYC gene in the industrial microorganisms can promote production of the different kinds of organic acids and intracellular and extracellular lipids. Therefore, the Pyc from different sources is regarded as a key enzyme in microbial biotechnology and is an important target for metabolic engineering of the industrial microbial strains. However, very little is known about the native Pycs and their functions and regulation in the industrial microorganisms.


Assuntos
Proteínas de Bactérias/genética , Ácidos Dicarboxílicos/metabolismo , Proteínas Fúngicas/genética , Regulação Bacteriana da Expressão Gênica , Lipídeos/biossíntese , Piruvato Carboxilase/genética , Bactérias/enzimologia , Bactérias/genética , Proteínas de Bactérias/metabolismo , Dióxido de Carbono/metabolismo , Proteínas Fúngicas/metabolismo , Fungos/enzimologia , Fungos/genética , Expressão Gênica , Humanos , Microbiologia Industrial , Engenharia Metabólica/métodos , Piruvato Carboxilase/metabolismo
15.
Braz J Microbiol ; 50(3): 633-648, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31175657

RESUMO

Recalcitrant characteristics and insolubility in water make the disposal of synthetic polymers a great environmental problem to be faced by modern society. Strategies towards the recycling of post-consumer polymers, like poly (ethylene terephthalate, PET) degradation/depolymerization have been studied but still need improvement. To contribute with this purpose, 100 fungal strains from hydrocarbon-associated environments were screened for lipase and esterase activities by plate assays and high-throughput screening (HTS), using short- and long-chain fluorogenic probes. Nine isolates were selected for their outstanding hydrolytic activity, comprising the genera Microsphaeropsis, Mucor, Trichoderma, Westerdykella, and Pycnidiophora. Two strains of Microsphaeropsis arundinis were able to convert 2-3% of PET nanoparticle into terephthalic acid, and when cultured with two kinds of commercial PET bottle fragments, they also promoted weight loss, surface and chemical changes, increased lipase and esterase activities, and led to PET depolymerization with release of terephthalic acid at concentrations above 20.0 ppm and other oligomers over 0.6 ppm. The results corroborate that hydrocarbon-associated areas are important source of microorganisms for application in environmental technologies, and the sources investigated revealed important strains with potential for PET depolymerization.


Assuntos
Fungos/metabolismo , Polietilenotereftalatos/metabolismo , Biodegradação Ambiental , Esterases/metabolismo , Proteínas Fúngicas/metabolismo , Fungos/enzimologia , Hidrocarbonetos/química , Hidrocarbonetos/metabolismo , Lipase/metabolismo , Polietilenotereftalatos/química , Polimerização
16.
Int J Mol Sci ; 20(12)2019 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-31234541

RESUMO

Omega-3 long chain polyunsaturated fatty acids (ω3 LC-PUFAs) such as eicosapentaenoic acid (EPA; 20:5ω3) and docosahexaenoic acid (DHA; 22:6ω3) are important fatty acids for human health. These ω3 LC-PUFAs are produced from their ω3 precursors by a set of desaturases and elongases involved in the biosynthesis pathway and are also converted from ω6 LC-PUFA by omega-3 desaturases (ω3Ds). Here, we have investigated eight ω3-desaturases obtained from a cyanobacterium, plants, fungi and a lower animal species for their activities and compared their specificities for various C18, C20 and C22 ω6 PUFA substrates by transiently expressing them in Nicotiana benthamiana leaves. Our results showed hitherto unreported activity of many of the ω3Ds on ω6 LC-PUFA substrates leading to their conversion to ω3 LC-PUFAs. This discovery could be important in the engineering of EPA and DHA in heterologous hosts.


Assuntos
Ácidos Graxos Dessaturases/metabolismo , Ácidos Graxos Ômega-3/metabolismo , Animais , Cianobactérias/enzimologia , Fungos/enzimologia , Plantas/enzimologia , Plantas Geneticamente Modificadas , Especificidade por Substrato , Tabaco/genética
17.
Appl Microbiol Biotechnol ; 103(14): 5517-5532, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31129742

RESUMO

The secretion of proteases by certain species of yeast and filamentous fungi is of importance not only for their biological function and survival, but also for their biotechnological application to various processes in the food, beverage, and bioprocessing industries. A key step towards understanding the role that these organisms play in their environment, and how their protease-secreting ability may be optimally utilised through industrial applications, involves an evaluation of those factors which influence protease production. The objective of this review is to provide an overview of the findings from investigations directed at elucidating the regulatory mechanisms underlying extracellular protease secretion in yeast and filamentous fungi, and the environmental stimuli that elicit these responses. The influence of nitrogen-, carbon-, and sulphur-containing compounds, as well as proteins, temperature, and pH, on extracellular protease regulation, which is frequently exerted at the transcriptional level, is discussed in particular depth. Protease-secreting organisms of biotechnological interest are also presented in this context, in an effort to explore the areas of industrial significance that could possibly benefit from such knowledge. In this way, the establishment of a platform of existing knowledge regarding fungal protease regulation is attempted, with the particular goal of aiding in the practical application of these organisms to processes that require secretion of this enzyme.


Assuntos
Biotecnologia/métodos , Fungos/enzimologia , Fungos/genética , Regulação Fúngica da Expressão Gênica , Peptídeo Hidrolases/genética , Carbono/metabolismo , Proteínas Fúngicas/genética , Concentração de Íons de Hidrogênio , Nitrogênio/metabolismo , Temperatura , Leveduras/enzimologia , Leveduras/genética
18.
Top Curr Chem (Cham) ; 377(3): 17, 2019 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-31134390

RESUMO

In this article, the utilization of fungi for the degradation of xenobiotic organic compounds (XOCs) from different wastewater and aqueous solutions has been reviewed. The myco-remediation (myco-enzymes, myco-degradation, and myco-sorption) process is widely used to remove XOCs, which are not easily biodegradable. The removal of XOCs from textile wastewaters through chemical and physical processes has been addressed by many researchers. Currently, the application of oxidative enzymes [manganese peroxidase (MnP), lignin peroxidase (LiP), and laccase] and myco-adsorption is becoming more common for the removal of XOCs from wastewater. Although the advanced oxidation process (AOPs) is a preferred technology for removing XOCs, its use is restricted due to its relatively high cost, which led to research studies on non-traditional and low-cost technology. The current review aimed to organize the scattered available information on the potential of myco-remediation for XOC removal. Moreover, the utilization of agricultural wastes as a production substrate for oxidative enzymes has been reported by many authors. Agricultural waste materials are highly inducible for oxidative enzyme production by fungi and are cost-effective in comparison to commercial substances. It is evident from the literature survey of 80 recently published papers that myco-enzymes have demonstrated outstanding XOC removal capabilities. Fungal laccase enzyme is the first step to degrade the lignin and then to get the carbon source form the cellulose by cellulose enzyme.


Assuntos
Biodegradação Ambiental , Compostos Orgânicos/metabolismo , Xenobióticos/metabolismo , Adsorção , Fungos/enzimologia , Oxirredutases/metabolismo , Eliminação de Resíduos Líquidos
19.
Adv Exp Med Biol ; 1142: 115-129, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31102244

RESUMO

Lytic polysaccharide monooxygenases (LPMOs) are copper-dependent enzymes that catalyze the cleavage of 1,4-glycosidic bonds various plant cell wall polysaccharides and chitin. In contrast to glycoside hydrolases, LPMOs are active on the crystalline regions of polysaccharides and thus synergize with hydrolytic enzymes. This synergism leads to an overall increase in the biomass-degradation activity of enzyme mixtures. Chitin-active LPMOs were discovered in 2010 and are currently classified in families AA10, AA11, and AA15 of the Carbohydrate-Active enZYmes database, which include LPMOs from bacteria, fungi, insects, and viruses. LPMOs have become important enzymes both industrially and scientifically and, in this chapter, we provide a brief introduction to chitin-active LPMOs including a summary of the 20+ chitin-active LPMOs that have been characterized so far. Then, we describe their structural features, catalytic mechanism, and appended carbohydrate modules. Finally, we show how chitin-active LPMOs can be used to perform chemo-enzymatic modification of chitin substrates.


Assuntos
Quitina/química , Oxigenases de Função Mista , Animais , Bactérias/enzimologia , Parede Celular , Fungos/enzimologia , Glicosídeo Hidrolases , Insetos/enzimologia , Vírus/enzimologia
20.
World J Microbiol Biotechnol ; 35(5): 70, 2019 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-31011828

RESUMO

Cyanide is a nitrile which is used extensively in many industries like jewelry, mining, electroplating, plastics, dyes, paints, pharmaceuticals, food processing, and coal coking. Cyanides pose a serious health hazard due to their high affinity towards metals and cause malfunction of cellular respiration by inhibition of cytochrome c oxidase. This inhibition ultimately leads to histotoxic hypoxia, increased acidosis, reduced the functioning of the central nervous system and myocardial activity. Different physicochemical processes including oxidation by hydrogen peroxide, alkaline chlorination, and ozonization have been used to reduce cyanide waste from the environment. Microbial cyanide degradation which is considered as one the most successful techniques is used to take place through different biochemical/metabolic pathways involving reductive, oxidative, hydrolytic or substitution/transfer reactions. Groups of enzymes involved in microbial degradation are cyanidase, cyanide hydratase, formamidase, nitrilase, nitrile hydratase, cyanide dioxygenase, cyanide monooxygenase, cyanase and nitrogenase. In the future, more advancement of omics technologies and protein engineering will help us to recoup the environment from cyanide effluent. In this review, we have discussed the origin and environmental distribution of cyanide waste along with different bioremediation pathways and enzymes involved therein.


Assuntos
Bactérias/enzimologia , Cianetos/metabolismo , Fungos/enzimologia , Resíduos Industriais/análise , Plantas/enzimologia , Amidoidrolases , Aminoidrolases , Bactérias/classificação , Bactérias/metabolismo , Biodegradação Ambiental , Carbono-Nitrogênio Liases , Cianetos/toxicidade , Fungos/metabolismo , Hidroliases , Hidrolases , Microbiologia Industrial , Nitrogenase , Oxirredução , Plantas/classificação , Plantas/metabolismo , Sulfurtransferases , Tiossulfato Sulfurtransferase
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