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1.
Sheng Wu Gong Cheng Xue Bao ; 36(5): 932-941, 2020 May 25.
Artigo em Chinês | MEDLINE | ID: mdl-32567276

RESUMO

Endo-ß-N-acetylglucosaminidase is used widely in the glycobiology studies and industries. In this study, a new endo-ß-N-acetylglucosaminidase, designated as Endo SA, was cloned from Streptomyces alfalfae ACCC 40021 and expressed in Escherichia coli BL21 (DE3). The purified recombinant Endo SA exhibited the maximum activity at 35 ºC and pH 6.0, good thermo/pH stability and high specific activity (1.0×106 U/mg). It displayed deglycosylation activity towards different protein substrates. These good properties make EndoSA a potential tool enzyme and industrial biocatalyst.


Assuntos
Manosil-Glicoproteína Endo-beta-N-Acetilglucosaminidase , Streptomyces , Clonagem Molecular , Estabilidade Enzimática , Escherichia coli/genética , Expressão Gênica , Manosil-Glicoproteína Endo-beta-N-Acetilglucosaminidase/genética , Manosil-Glicoproteína Endo-beta-N-Acetilglucosaminidase/metabolismo , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Streptomyces/enzimologia , Streptomyces/genética
2.
Bioresour Technol ; 313: 123692, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32570080

RESUMO

The effect of Streptomyces griseorubens JSD-1 inoculant on composting performance and bacterial community assembly during the swine manure and rice straw co-composting was studied by a high-throughput pyrosequencing technology. The JSD-1 inoculant contributed to a higher temperature (maximum 66.8 °C), a longer thermophilic phase (46 days), and a lower bacterial diversity in JSD-1 compost. The principle component analysis confirmed that JSD-1 inoculant significantly reshaped the microbial communities. The difference in genera significantly increased during both composting processes. The predominant biomarkers were members of Bacteroidetes in JSD-1 composting. The network analysis also showed different chief "connecting" genera in both composts. Moreover, JSD-1 inoculant increased the total nitrogen, phosphorus, and potassium content in composts. The redundancy analysis showed that the bacterial community was mainly influenced by temperature; additionally, the nutrient contents were positively correlated with temperature. These results demonstrated that JSD-1 inoculant drove the bacterial assembly to induce physicochemical property changes in co-composting.


Assuntos
Compostagem , Oryza , Streptomyces , Animais , Esterco , Solo , Suínos
3.
Plant Dis ; 104(7): 1986-1993, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32441579

RESUMO

Potato common scab is an important soilborne disease worldwide that can significantly reduce the quality and economic values of potato. The disease is caused by multiple species of Streptomyces, which are not well controlled due to lack of effective strategies. Streptomyces galilaeus has been recently identified as a dominant species causing potato common scab in Inner Mongolia, China. This study was focused on screening and characterizing antagonists for biological control against pathogenic S. galilaeus. Bacterial strain PBSH9 was isolated from a potato tuber. PBSH9 was identified as a Streptomyces sp. on the basis of morphological, physiological, and biochemical characteristics, as well as DNA sequence analysis. PBSH9 inhibited S. galilaeus with a diameter of inhibitory zone of 19.8 mm on agar plates. The extracellular filtrate of PBSH9 also inhibited S. galilaeus growth with a diameter of inhibition zone of 10.0 mm. Furthermore, PBSH9 promoted potato sprouting and emergence. Disease control was up to 81.88% in greenhouse trials, and from 47.64 to 73.97% in 3-year field trials. Among the tested inoculation methods, seed treatment was more effective than soil drenching for PBSH9 application. PBSH9 not only effectively controlled potato common scab but also increased potato growth. Thus, it can be a potential candidate for biocontrol agent.


Assuntos
Solanum tuberosum , Streptomyces , China , Doenças das Plantas
4.
Proc Natl Acad Sci U S A ; 117(19): 10265-10270, 2020 05 12.
Artigo em Inglês | MEDLINE | ID: mdl-32350138

RESUMO

Coformycin and pentostatin are structurally related N-nucleoside inhibitors of adenosine deaminase characterized by an unusual 1,3-diazepine nucleobase. Herein, the cof gene cluster responsible for coformycin biosynthesis is identified. Reconstitution of the coformycin biosynthetic pathway in vitro demonstrates that it overlaps significantly with the early stages of l-histidine biosynthesis. Committed entry into the coformycin pathway takes place via conversion of a shared branch point intermediate to 8-ketocoformycin-[Formula: see text]-monophosphate catalyzed by CofB, which is a homolog of succinylaminoimidazolecarboxamide ribotide (SAICAR) synthetase. This reaction appears to proceed via a Dieckmann cyclization and a retro-aldol elimination, releasing ammonia and D-erythronate-4-phosphate as coproducts. Completion of coformycin biosynthesis involves reduction and dephosphorylation of the CofB product, with the former reaction being catalyzed by the NADPH-dependent dehydrogenase CofA. CofB also shows activation by adenosine triphosphate (ATP) despite the reaction requiring neither a phosphorylated nor an adenylated intermediate. This may serve to help regulate metabolic partitioning between the l-histidine and coformycin pathways.


Assuntos
Adenosina Desaminase/química , Trifosfato de Adenosina/metabolismo , Proteínas de Bactérias/genética , Coformicina/biossíntese , Família Multigênica , Streptomyces/genética , Adenosina Desaminase/metabolismo , Monofosfato de Adenosina/metabolismo , Proteínas de Bactérias/química , Proteínas de Bactérias/metabolismo , Vias Biossintéticas , Fosforilação , Streptomyces/metabolismo
5.
PLoS One ; 15(5): e0232927, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32396566

RESUMO

Tetraene macrolides remain one of the most reliable fungicidal agents as resistance of fungal pathogens to these antibiotics is relatively rare. The modes of action and biosynthesis of polyene macrolides had been the focus of research over the past few years. However, few studies have been carried out on the overproduction of polyene macrolides. In the present study, cumulative drug-resistance mutation was used to obtain a quintuple mutant G5-59 with huge tetraene macrolide overproduction from the starting strain Streptomyces diastatochromogenes 1628. Through DNA sequence analysis, the mutation points in the genes of rsmG, rpsL and rpoB were identified. Additionally, the growth characteristic and expression level of tetrRI gene (belonging to the large ATP binding regulator of LuxR family) involved in the biosynthesis of tetraene macrolides were analyzed. As examined with 5L fermentor, the quintuple mutant G5-59 grew very well and the maximum productivity of tetramycin A, tetramycin P and tetrin B was as high as 1735, 2811 and 1500 mg/L, which was 8.7-, 16- and 25-fold higher than that of the wild-type strain 1628, respectively. The quintuple mutant G5-59 could be useful for further improvement of tetraene macrolides production at industrial level.


Assuntos
Proteínas de Bactérias/genética , Reatores Biológicos/microbiologia , Macrolídeos/metabolismo , Mutação , Streptomyces/crescimento & desenvolvimento , RNA Polimerases Dirigidas por DNA/genética , Farmacorresistência Bacteriana , Fermentação , Engenharia Metabólica , Metiltransferases/genética , Proteínas Ribossômicas/genética , Análise de Sequência de DNA , Streptomyces/genética , Streptomyces/metabolismo
6.
Int J Syst Evol Microbiol ; 70(5): 3226-3233, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32375929

RESUMO

A novel actinomycete, designated strain NEAU-C151T, was isolated from soil collected from Mount Song and characterized using a polyphasic approach. Analysis of the 16S rRNA gene sequence indicated that strain NEAU-C151T belongs to the genus Streptomyces and exhibited 97.5, 97.4 and 97.4 % similarities to Streptomyces lincolnensis NRRL 2936T, Streptomyces coacervatus AS-0823T, and Streptomyces longisporus ISP 5166T, respectively. The assignment of strain NEAU-C151T to the genus Streptomyces was confirmed by chemotaxonomic data: anteiso-C15 : 0, C16 : 0, iso-C16 : 0, C16 : 1 (ω7c) and anteiso-C17 : 0 as the major cellular fatty acids; whole-cell sugars contained ribose and glucose; phospholipid profile consisted of diphosphatidylglycerol (DPG), phosphatidylethanolamine (PE), unidentified phospholipid (PL), unidentified lipids (L) and phosphatidylinositol mannoside (PIM); the menaquinones were MK-9(H4), MK-9(H6), MK-10(H2) and MK-9(H8). However, multilocus sequence analysis based on five other house-keeping genes (atpD, gyrB, recA, rpoB, and trpB), DNA-DNA relatedness and phenotypic data showed that strain NEAU-C151T could be distinguished from its closest relatives. Consequently, strain NEAU-C151T represents a novel species of the genus Streptomyces, for which the name Streptomyces montanus sp. nov. is proposed. The type strain is NEAU-C151T (=CGMCC 4.7498T=DSM 107808T).


Assuntos
Filogenia , Microbiologia do Solo , Streptomyces/classificação , Actinobacteria/genética , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , Genes Bacterianos , Tipagem de Sequências Multilocus , Hibridização de Ácido Nucleico , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Streptomyces/isolamento & purificação , Vitamina K 2/análogos & derivados , Vitamina K 2/química
7.
Int J Syst Evol Microbiol ; 70(5): 3316-3322, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32375984

RESUMO

An endophytic actinomycete, strain 3MP-10T, isolated from the root of Mimosa pudica was taxonomically studied based upon polyphasic approaches. This strain formed spiral spore chains on aerial mycelia. ll-Diaminopimelic acid, glucose and ribose were found in the whole-cell hydrolysates. It belonged to the genus Streptomyces and was closely related to Streptomyces zhaozhouensis DSM 42101T (98.9 %) and Streptomyces sedi JCM 16909T (98.6 %) based on 16S rRNA gene sequence analysis results. The major menaquinones were MK-10(H8), MK-10(H6) and MK-9(H8). The predominant cellular fatty acids were iso-C16 : 0, anteiso-C15 : 0 and anteiso-C17 : 0. The detected phospholipids were diphosphatidylglycerol, phosphatidylinositol mannoside, phosphatidylinositol, phosphatidylethanolamine and phosphatidylglycerol. Strain 3MP-10T had a genome size of 7.2 Mb with a genome G+C content of 73.4 mol%. Results of in silico genome-based similarity analysis revealed ANIb values of 84.94 and 84.77 %, ANIm values of 88.01 and 87.92 %, and dDDH values of 29.9 and 29.6 % when compared with S. zhaozhouensis DSM 42101T and S. sedi JCM 16909T, respectively. Based on the polyphasic approach, digital DNA-DNA relatedness and average nucleotide identity, we propose that the novel actinomycete represents a novel species, Streptomyces mimosae, with type strain 3MP-10T (=JCM 33328T=TISTR 2646T).


Assuntos
Mimosa/microbiologia , Filogenia , Raízes de Plantas/microbiologia , Streptomyces/classificação , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácido Diaminopimélico/química , Ácidos Graxos/química , Hibridização de Ácido Nucleico , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Streptomyces/isolamento & purificação , Tailândia , Vitamina K 2/química
8.
Int J Syst Evol Microbiol ; 70(6): 3924-3929, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32441614

RESUMO

Phylogenetic analysis based on 16S rRNA gene sequences of the genus Streptomyces showed the presence of six distinguishable clusters, with 100 % sequence similarity values among strains in each cluster; thus they shared almost the same evolutionary distance. This result corroborated well with the outcome of core gene (orthologous gene clusters) based genome phylogeny analysis of 190 genomes including the Streptomyces species in those six clusters. These preeminent results led to an investigation of genome-based indices such as digital DNA-DNA hybridization (dDDH), average nucleotide identity (ANI) and average amino acid identity (AAI) for the strains in those six clusters. Certain strains recorded genomic indices well above the threshold values (70 %, 95-96 % and >95 % for dDDH, ANI and AAI, respectively) determined for species affiliation, suggesting only one type strain belongs to described species and the other(s) may need to be reduced in taxa to a later heterotypic synonym. To conclude, the results of comprehensive analyses based on phylogenetic and genomic indices suggest that the following six reclassifications are proposed: Streptomyces flavovariabilis as a later heterotypic synonym of Streptomyces variegatus; Streptomyces griseofuscus as a later heterotypic synonym of Streptomyces murinus; Streptomyces kasugaensis as a later heterotypic synonym of Streptomyces celluloflavus; Streptomyces luridiscabiei as a later heterotypic synonym of Streptomyces fulvissimus; Streptomyces pharetrae as a later heterotypic synonym of Streptomyces glaucescens; and Streptomyces stelliscabiei as a later heterotypic synonym of Streptomyces bottropensis.


Assuntos
Filogenia , Streptomyces/classificação , DNA Bacteriano/genética , Hibridização de Ácido Nucleico , RNA Ribossômico 16S/genética
9.
Int J Syst Evol Microbiol ; 70(5): 3076-3083, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32228806

RESUMO

Strain ATCC 31180T was isolated from soil collected in Hyde Park, Massachusetts (USA), and found to produce the polyether antibiotic lasalocid. The name 'Streptomyces lasaliensis' has been in common use since 1974, without a recognized taxonomic description. The most closely related type cultures determined by rRNA gene sequence similarity were Streptomyces longwoodensis DSM 41677T (100 %) and Streptomyces galbus DSM 40089T (100 %). OrthoANI values with S. longwoodensis and S. galbus were 95.50 and 94.41 %, respectively. Chemotaxonomic characteristics supported inclusion within the genus Streptomyces. The cell wall peptidoglycan contained ll-diaminopimelic acid, and the major whole-cell sugars were glucose and ribose. Polar lipids were phosphatidylethanolamine, diphosphatidylglycerol, phosphatidylinositol, phosphatidylglycerol, one unidentified lipid and one unidentified glycolipid. The major menaquinones detected were MK9(H4), MK9(H6) and MK9(H8). The major cellular fatty acids were anteiso-C15 : 0, anteiso-C17 : 0, iso-C16 : 0, iso-C15 : 0 and anteiso-C17 : 1. Its DNA had a G+C content of 72.6 %. Differentiation of ATCC 31180T from the closely related species was evident from digital DNA-DNA hybridization values of 61.80 and 56.90 % for S. longwoodensis and S. galbus respectively. Significant differences were seen in the polyphasic phenotypic analyses. ATCC 31180T produced lasalocid, grew from 10 to 45 °C, pH4-8 and in the presence of 0-10 % NaCl, 0.01 % NaN3 and 1 % phenol. Melanin was produced; H2S and indole were not. Nitrate was not reduced. Spore chains were retinaculum-apertum and spore surfaces were smooth. Spore colour, mycelia colour and soluble pigment production were medium-dependent. The proposed name is Streptomyces lasalocidi sp. nov.; the type strain being ATCC 31180T (=NRRL 3382T=DSM 46487T).


Assuntos
Antibacterianos/biossíntese , Lasalocida/biossíntese , Filogenia , Microbiologia do Solo , Streptomyces/classificação , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácido Diaminopimélico/análise , Ácido Diaminopimélico/química , Ácidos Graxos/química , Massachusetts , Hibridização de Ácido Nucleico , Peptidoglicano/química , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Streptomyces/isolamento & purificação , Vitamina K 2/análogos & derivados , Vitamina K 2/química
11.
Nat Commun ; 11(1): 1614, 2020 03 31.
Artigo em Inglês | MEDLINE | ID: mdl-32235841

RESUMO

The heterocycle 1,2,3-triazole is among the most versatile chemical scaffolds and has been widely used in diverse fields. However, how nature creates this nitrogen-rich ring system remains unknown. Here, we report the biosynthetic route to the triazole-bearing antimetabolite 8-azaguanine. We reveal that its triazole moiety can be assembled through an enzymatic and non-enzymatic cascade, in which nitric oxide is used as a building block. These results expand our knowledge of the physiological role of nitric oxide synthase in building natural products with a nitrogen-nitrogen bond, and should also inspire the development of synthetic biology approaches for triazole production.


Assuntos
Bactérias/metabolismo , Óxido Nítrico/metabolismo , Triazóis/metabolismo , Azaguanina/metabolismo , Bactérias/enzimologia , Bactérias/genética , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Produtos Biológicos , Vias Biossintéticas/genética , Genes Bacterianos/genética , Óxido Nítrico Sintase/metabolismo , Nitrogênio , Streptomyces/enzimologia , Streptomyces/genética , Streptomyces/metabolismo , Biologia Sintética
12.
Nat Rev Microbiol ; 18(6): 316-317, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32273596
13.
PLoS One ; 15(3): e0230531, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32191748

RESUMO

Among several studied strains, Streptomyces rochei IT20 and S. vinaceusdrappus SS14 showed a high level of inhibitory effect against Phytophthora capsici, the causal agent of pepper blight. The effect of two mentioned superior antagonists, as single or combination treatments, on suppression of stem and fruit blight diseases and reproductive growth promotion was investigated in pepper. To explore the induced plant defense reactions, ROS generation and transcriptional changes of selected genes in leaf and fruit tissues of the plant were evaluated. The plants exposed to the combination of two species responded differently in terms of H2O2 accumulation and expression ratio of GST gene compared to single treatments upon pathogen inoculation. Besides, the increment of shoot length, flowering, and fruit weight were observed in healthy plants compared to control. Likely, these changes depended on the coordinated relationships between PR1, ACCO genes and transcription factors WRKY40 enhanced after pathogen challenge. Our findings indicate that appropriate tissue of the host plant is required for inducing Streptomyces-based priming and relied on the up-regulation of SUS and differential regulation of ethylene-dependent genes.


Assuntos
Capsicum/microbiologia , Especificidade de Órgãos , Phytophthora/fisiologia , Streptomyces/fisiologia , Aminobutiratos/farmacologia , Capsicum/genética , Capsicum/crescimento & desenvolvimento , Frutas/genética , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Peróxido de Hidrogênio/metabolismo , Especificidade de Órgãos/genética , Doenças das Plantas/genética , Doenças das Plantas/microbiologia , Folhas de Planta/genética
14.
Int J Syst Evol Microbiol ; 70(4): 2750-2759, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32176603

RESUMO

A novel actinobacterial strain, designated 13K301T, was isolated from a soil sample collected from the Karakum Desert, Turkmenistan. The taxonomic position of strain 13K301T was revealed by using a polyphasic approach. On the basis of 16S rRNA gene sequence analysis, strain 13K301T belongs to the genus Streptomyces and had highest sequence similarity to 'Streptomyces qaidamensis' S10T (99.2 %), Streptomyces flavovariabilis NRRL B-16367T (98.9 %) and Streptomyces phaeoluteigriseus DSM 41896T (98.8 %), but the strain formed a distinct clade in the phylogenetic tree. The DNA-DNA relatedness and average nucleotide identity values as well as evolutionary distances based on multilocus (atpD, gyrB, recA, rpoB and trpB) sequences between strain 13K301T and closely related type strains were significantly lower than the recommended threshold values. The cell wall contained ll-diaminopimelic acid and the whole-cell hydrolysates were glucose and ribose. Diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol and phosphatidylinositol were determined as the predominant polar lipids. The major menaquinones were identified as MK-9(H8) and MK-9(H6). On the basis of these genotypic and phenotypic data, it is proposed that strain 13K301T should be classified as representative of a novel species of the genus Streptomyces, for which the name Streptomyces cahuitamycinicus sp. nov. is proposed. The type strain is 13K301T (=DSM 106873T=KCTC 49110T). In addition, the whole genome-based comparisons as well as the multilocus sequence analysis revealed that the type strains of Streptomyces galilaeus and Streptomyces bobili belong to a single species. It is, therefore, proposed that S. galilaeus be recognised as a heterotypic synonym of S. bobili for which an emended description is given.


Assuntos
Clima Desértico , Filogenia , Microbiologia do Solo , Streptomyces/classificação , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácido Diaminopimélico/química , Ácidos Graxos/química , Genes Bacterianos , Hibridização de Ácido Nucleico , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Streptomyces/isolamento & purificação , Turcomenistão , Vitamina K 2/análogos & derivados , Vitamina K 2/química
15.
Int J Syst Evol Microbiol ; 70(4): 2760-2765, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32195647

RESUMO

A novel actinobacterium, designated TRM68348T, was isolated from the silt collected from the Tailan River in Xinjiang Province, north-west China. The strain was aerobic and Gram-stain-positive. The aerial mycelium was densely straight or tortuous, with a few branches of hyphae and no spores. The whole-cell sugar pattern of strain TRM68348T consisted of ribose and glucose. The diagnostic diamino was ll-diaminopimelic acid. The polar lipids were diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylcholine, phosphatidylinositol, phosphatidylinositol mannose and an unidentified phospholipid. The predominant menaquinones were MK-9 (H10), MK-9 (H6) and MK-9 (H2). The major fatty acids (>5 %) were iso-C14 : 0, iso-C15 : 0, anteiso-C15 : 0, iso-C16 : 0, C16 : 0 and summed feature 6. The G+C content of the genomic DNA was 69.93 mol%. Phylogenetic analysis showed that strain TRM68348T shared 16S rRNA gene sequence similarity of 98.14 % to the closest described species Streptomyces capitiformicae 1H-SSA4T. Strain TRM68348T had a relatively low DNA-DNA relatedness value with S. capitiformicae 1H-SSA4T as determined by calculating the average nucleotide identity value (92.78 %). Strain TRM68348T could also be differentiated from S. capitiformicae 1H-SSA4T based on morphological and physiological characteristics. On the basis of the evidence from this polyphasic study, the strain is concluded to represent a novel species of the genus Streptomyces, for which the name Streptomyces tailanensis sp. nov. is proposed. The type strain is TRM68348T (=CCTCC AA 2018086T=KCTC 49274T).


Assuntos
Sedimentos Geológicos/microbiologia , Filogenia , Rios/microbiologia , Streptomyces/classificação , Técnicas de Tipagem Bacteriana , Composição de Bases , China , DNA Bacteriano/genética , Ácido Diaminopimélico/química , Ácidos Graxos/química , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Streptomyces/isolamento & purificação , Vitamina K 2/análogos & derivados , Vitamina K 2/química
16.
Microbes Environ ; 35(1)2020.
Artigo em Inglês | MEDLINE | ID: mdl-32101840

RESUMO

The genome of Streptomyces scabies, the predominant causal agent of potato common scab, encodes a potential cutinase, the protein Sub1, which was previously shown to be specifically induced in the presence of suberin. The sub1 gene was expressed in Escherichia coli and the recombinant protein Sub1 was purified and characterized. The enzyme was shown to be versatile because it hydrolyzes a number of natural and synthetic substrates. Sub1 hydrolyzed p-nitrophenyl esters, with the hydrolysis of those harboring short carbon chains being the most effective. The Vmax and Km values of Sub1 for p-nitrophenyl butyrate were 2.36 mol g-1 min-1 and 5.7 10-4 M, respectively. Sub1 hydrolyzed the recalcitrant polymers cutin and suberin because the release of fatty acids from these substrates was observed following the incubation of the enzyme with these polymers. Furthermore, the hydrolyzing activity of the esterase Sub1 on the synthetic polymer polyethylene terephthalate (PET) was demonstrated by the release of terephthalic acid (TA). Sub1 activity on PET was markedly enhanced by the addition of Triton and was shown to be stable at 37°C for at least 20 d.


Assuntos
Proteínas de Bactérias/metabolismo , Hidrolases de Éster Carboxílico/metabolismo , Doenças das Plantas/microbiologia , Polímeros/metabolismo , Streptomyces/enzimologia , Proteínas de Bactérias/genética , Proteínas de Bactérias/isolamento & purificação , Hidrolases de Éster Carboxílico/genética , Hidrolases de Éster Carboxílico/isolamento & purificação , Ácidos Graxos/metabolismo , Hidrólise , Ácidos Ftálicos/metabolismo , Proteínas Recombinantes/genética , Proteínas Recombinantes/isolamento & purificação , Proteínas Recombinantes/metabolismo , Solanum tuberosum/microbiologia , Streptomyces/genética
17.
J Agric Food Chem ; 68(10): 3184-3194, 2020 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-32105462

RESUMO

Enzymatic hydrolysis of xylan represents a promising way to produce xylooligosaccharide (XOS), which is a novel ingredient in functional food. However, the recalcitrance of xylan in natural lignocellulosic biomass entails effective and robust xylanases. In the present study, we reported the isolation of a thermophilic Streptomyces sp. B6 from mushroom compost producing high xylanase activity. Two xylanases of Streptomyces sp. B6 belonging to GH10 (XynST10) and GH11 (XynST11) families were thus identified and biochemically characterized to be robust enzymes with high alkaline- and thermostability. Direct hydrolysis of neutralized viscose fiber production waste using XynST10 and XynST11 showed that while XynST10 produced 23.22 g/L XOS with a degree of polymerization (DP) of 2-4 and 9.27 g/L xylose, XynST11 produced much less xylose (1.19 g/L) and a higher amounts of XOS with a DP = 2-4 (28.29 g/L). Thus, XynST11 holds great potential for the production of XOS from agricultural and industrial waste.


Assuntos
Proteínas de Bactérias/química , Endo-1,4-beta-Xilanases/química , Glucuronatos/química , Oligossacarídeos/química , Streptomyces/enzimologia , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Biocatálise , Endo-1,4-beta-Xilanases/genética , Endo-1,4-beta-Xilanases/metabolismo , Estabilidade Enzimática , Glucuronatos/metabolismo , Temperatura Alta , Concentração de Íons de Hidrogênio , Resíduos Industriais/análise , Oligossacarídeos/metabolismo , Streptomyces/química , Streptomyces/genética , Xilose/química , Xilose/metabolismo
18.
Sci Total Environ ; 713: 136708, 2020 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-32019044

RESUMO

Consumption of water containing high proportions of manganese could cause Parkinson's like symptoms and damage the central nervous systems. This study aims to investigate the potential of manganese removal through the development of microbial cell-immobilized biochar. The wood vinegar industry generates a large volume of carbonized wood waste (natural biochar) from the pyrolytic process. This is the first investigation utilizing this low value waste combined with biological treatment for water purification. Raw and hydrogen peroxide-modified biochars were used to immobilize an effective manganese-oxidizing bacterium, Streptomyces violarus strain SBP1 (SBP1). The results demonstrated that the modified biochar had a higher proportion of oxygen-containing functional groups leading to better manganese removal. Manganese adsorption by the modified biochar fitted pseudo-second-order and Langmuir models with the maximum adsorption capacity of 1.15 mg g-1. The modified biochar with SBP1 provided the highest removal efficiency at 78%. The advanced synchrotron analyses demonstrated that manganese removal by the biochar with SBP1 is due to the synergistic combination of manganese adsorption by biochars and biological oxidation by SBP1.


Assuntos
Streptomyces , Adsorção , Biotransformação , Carvão Vegetal , Manganês , Poluentes Químicos da Água
19.
Mol Cell ; 77(3): 443-445, 2020 02 06.
Artigo em Inglês | MEDLINE | ID: mdl-32032510

RESUMO

A recent paper by Gallagher et al. (2020) demonstrates that c-di-GMP controls spore formation in Streptomyces venezuelae through sequestering the sporulation sigma factor σWhiG and presents the crystal structure of a ternary complex between c-di-GMP, σWhiG, and its anti-sigma factor, RsiG.


Assuntos
Streptomyces , Proteínas de Bactérias , Diferenciação Celular , GMP Cíclico/análogos & derivados , Fator sigma
20.
Microbes Environ ; 35(1)2020.
Artigo em Inglês | MEDLINE | ID: mdl-31932540

RESUMO

Chitin amendment is an agricultural management strategy for controlling soil-borne plant disease. We previously reported an exponential decrease in chitin added to incubated upland soil. We herein investigated the transition of the bacterial community structure in chitin-degrading soil samples over time and the characteristics of chitinolytic bacteria in order to elucidate changes in the chitinolytic bacterial community structure during chitin degradation. The addition of chitin to soil immediately increased the population of bacteria in the genus Streptomyces, which is the main decomposer of chitin in soil environments. Lysobacter, Pseudoxanthomonas, Cellulosimicrobium, Streptosporangium, and Nonomuraea populations increased over time with decreases in that of Streptomyces. We isolated 104 strains of chitinolytic bacteria, among which six strains were classified as Lysobacter, from chitin-treated soils. These results suggested the involvement of Lysobacter as well as Streptomyces as chitin decomposers in the degradation of chitin added to soil. Lysobacter isolates required yeast extract or casamino acid for significant growth on minimal agar medium supplemented with glucose. Further nutritional analyses demonstrated that the six chitinolytic Lysobacter isolates required methionine (Met) to grow, but not cysteine or homocysteine, indicating Met auxotrophy. Met auxotrophy was also observed in two of the five type strains of Lysobacter spp. tested, and these Met auxotrophs used d-Met as well as l-Met. The addition of Met to incubated upland soil increased the population of Lysobacter. Met may be a factor increasing the population of Lysobacter in chitin-treated upland soil.


Assuntos
Bactérias/isolamento & purificação , Bactérias/metabolismo , Quitina/farmacologia , Metionina/metabolismo , Microbiota/efeitos dos fármacos , Microbiologia do Solo , Bactérias/classificação , Bactérias/genética , Quitina/análise , Quitina/metabolismo , Lysobacter/classificação , Lysobacter/genética , Lysobacter/isolamento & purificação , Lysobacter/metabolismo , Filogenia , RNA Ribossômico 16S/genética , Solo/química , Streptomyces/classificação , Streptomyces/genética , Streptomyces/isolamento & purificação , Streptomyces/metabolismo
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