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1.
Rev Bras Parasitol Vet ; 28(3): 451-457, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31390434

RESUMO

The msp4 gene of A. marginale is unicodon, stable and mostly homogeneous, being considered as a useful marker for phylogeographic characterization of this bacterium. The objective of this work was to analyze the phylogeography of A. marginale based on the msp4 gene in beef cattle from the Brazilian Pantanal, compared to those found in other regions worldwide. The blood samples investigated were collected from 400 animals (200 cows and 200 calves) reared in five extensive breeding farms in this region. The results indicated that of the evaluated samples, 56.75% (227/400) were positive for A. marginale based on the msp1ß gene by quantitatitve PCR (qPCR), while 8.37% (19/227) were positive for the msp4 gene in the conventional PCR. In the Network distance analysis, 14 sequences from the Brazilian Pantanal were grouped into a single group with those from Thailand, India, Spain, Colombia, Parana (Brazil), Mexico, Portugal, Argentina, China, Venezuela, Australia, Italy and Minas Gerais (Brazil). Among 68 sequences from Brazil and the world, 15 genotypes were present while genotype number one (#1) was the most distributed worldwide. Both Splitstree and network analyses showed that the A. marginale msp4 sequences detected in beef cattle from the Brazilian Pantanal showed low polymorphism, with the formation of one genogroup phylogenetically related to those found in ruminants from South and Central America, Europe, and Asia.


Assuntos
Anaplasma marginale/genética , Proteínas de Bactérias/genética , Bovinos/microbiologia , Proteínas de Membrana/genética , Filogeografia/métodos , Américas , Sequência de Aminoácidos , Anaplasma marginale/isolamento & purificação , Animais , Ásia , Brasil , DNA Bacteriano/genética , Europa (Continente) , Feminino , Genótipo , Masculino , Dados de Sequência Molecular , Reação em Cadeia da Polimerase
2.
Arch Virol ; 164(9): 2297-2307, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31267215

RESUMO

The influence of the high genetic variability of hepatitis B virus (HBV) on the sensitivity of serological assays has received little attention so far. A major source of variability is related to viral genotypes and subgenotypes. Their possible influence on diagnosis and prophylaxis is poorly known and has mostly been evaluated for genotypes A, B, C and D. Robust data showing the detection efficiency of HBsAg from genotype F is lacking. This study examined the effect of virus-like particles containing HBsAg from genotypes A and F (particularly, F1b and F4) produced in Pichia pastoris in relation to the anti-HBs antibodies used in the immunoassays for in vitro diagnosis and compared it with that exerted by the G145R S-escape mutant. The results showed that HBsAg detection rates for subgenotypes F1b and F4 differed significantly from those obtained for genotype A and that subgenotype F1b had a major impact on the sensitivity of the immunoassays tested. Prediction of the tertiary structure of subgenotypes F1b and F4 revealed changes inside and outside the major hydrophilic region (aa 101-160) of the HBsAg compared to genotype A and the G145R variant. A phosphorylation site (target for protein kinase C) produced by the G145R substitution might prevent recognition by anti-HBs antibodies. In conclusion, the use of different genotypes or variants for diagnosis could improve the rate of detection of HBV infection. The incorporation of a genotype-F-derived HBsAg vaccine in areas where this genotype is endemic should be evaluated, since this might also affect vaccination efficacy.


Assuntos
Antígenos de Superfície da Hepatite B/genética , Vírus da Hepatite B/isolamento & purificação , Hepatite B/virologia , Sequência de Aminoácidos , Hepatite B/diagnóstico , Antígenos de Superfície da Hepatite B/química , Antígenos de Superfície da Hepatite B/metabolismo , Vírus da Hepatite B/química , Vírus da Hepatite B/classificação , Vírus da Hepatite B/genética , Humanos , Dados de Sequência Molecular , Mutação , Filogenia , Conformação Proteica , Alinhamento de Sequência
3.
Arch Virol ; 164(9): 2371-2374, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31165927

RESUMO

A previously undescribed badnavirus was identified in plants of Polyscias fruticosa (Ming aralia) showing symptoms of mild mosaic and leaf senescence. Characteristic bacilliform virions of the Polyscias badnavirus averaging 30 × 120 nm in size were observed by transmission electron microscopy in partially purified leaf tissue extracts from symptomatic but not asymptomatic plants collected in the USA and Nigeria. The isolate from the USA was complete sequenced. The genome is 7592 bp in length and contains three open reading frames with an arrangement similar to that of other members of the genus Badnavirus. The largest open reading frame (ORF3) encodes a putative polyprotein, with predicted domains including zinc finger, aspartic protease, reverse transcriptase (RT) and RNase H, in that order. The USA and Nigeria isolates of the virus had a high level (98%) of nucleotide sequence identity in the RT+RNase H region. Within the genus Badnavirus, these viruses were most closely related to schefflera ringspot virus (SRV), sharing 63% identity at the nucleotide level. Based on the ICTV species demarcation criteria for the genus Badnavirus (more than 20% nucleotide sequence divergence in the RT+RNase H region), the Polyscias virus is proposed to be a new member of the genus, and the name polyscias mosaic virus (PoMV) is proposed. The complete genome sequence was deposited in the NCBI GenBank database under accession no. MH475918.


Assuntos
Araliaceae/virologia , Badnavirus/isolamento & purificação , Genoma Viral , Doenças das Plantas/virologia , Badnavirus/classificação , Badnavirus/genética , Sequência de Bases , Dados de Sequência Molecular , Nigéria , Fases de Leitura Aberta , Filogenia , Folhas de Planta/virologia , Sequenciamento Completo do Genoma
4.
Arch Virol ; 164(9): 2327-2332, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31177352

RESUMO

Two distinct genotypes responsible for rabbit hemorrhagic disease (RHD) are reported, GI.1 (RHDV) and GI.2 (RHDV2). Vaccines based on these two genotypes are only partially cross-protective. Hence, knowing which genotype is circulating is important for appropriate control measures. We have investigated 25 field samples isolated between 2015 and 2018 from rabbits with clinical signs of RHD. Only GI.2 (RHDV2) is currently circulating in Tunisia. All Tunisian samples were grouped together with typical genotypic and phenotypic mutations. Therefore, we recommend initiating an extensive preventive vaccination program based on GI.2 vaccines in addition to a regular monitoring of the circulating lagoviruses.


Assuntos
Infecções por Caliciviridae/veterinária , Vírus da Doença Hemorrágica de Coelhos/genética , Vírus da Doença Hemorrágica de Coelhos/isolamento & purificação , Filogenia , Coelhos/virologia , Sequência de Aminoácidos , Animais , Infecções por Caliciviridae/epidemiologia , Infecções por Caliciviridae/virologia , Genótipo , Vírus da Doença Hemorrágica de Coelhos/química , Vírus da Doença Hemorrágica de Coelhos/classificação , Dados de Sequência Molecular , Alinhamento de Sequência , Tunísia/epidemiologia , Proteínas Virais/química , Proteínas Virais/genética , Proteínas Virais/metabolismo
5.
Arch Virol ; 164(9): 2375-2378, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31183555

RESUMO

The complete genomic RNA sequence of a tentative new umbravirus from Patrinia scabiosaefolia, tentatively named "patrinia mild mottle virus" (PatMMoV), was determined. The genome of PatMMoV consists of 4,214 nucleotides and has a typical umbravirus genome organization with four open reading frames. BLAST searches showed that the complete nucleotide sequence of PatMMoV had the highest identity (72%; 50% query coverage) to Ixeridium yellow mottle-associated virus 2 (IxYMaV-2; an unclassified umbravirus). In addition, phylogenetic analysis and pairwise comparisons showed that PatMMoV and IxYMaV-2 were the most closely related and placed in the same clade within a group of umbraviruses. These results suggest that PatMMoV is a putative new member of the genus Umbravirus in the family Tombusviridae.


Assuntos
Genoma Viral , Patrinia/virologia , Doenças das Plantas/virologia , Tombusviridae/genética , Tombusviridae/isolamento & purificação , Sequência de Bases , Dados de Sequência Molecular , Fases de Leitura Aberta , Filogenia , Tombusviridae/classificação , Sequenciamento Completo do Genoma
6.
Arch Virol ; 164(9): 2285-2295, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31250104

RESUMO

Examination of lumpy skin disease virus (LSDV) isolates from different geographic regions and times revealed that assays developed in our laboratory for differentiating between virulent Israeli viruses and Neethling vaccine virus (NVV) are generally useful in most, if not all, endemic areas in which NVV-based vaccines are used. Recently it was revealed that the LSDV126 gene of field isolates contains a duplicated region of 27 bp (9 aa), while the vaccine viruses have only one copy. Phylogenetic analysis of a 532-bp segment carrying the LSDV126 gene and whole virus genome sequences revealed that LSDV isolates formed two groups: virulent and vaccine viruses. In this analysis, all of the capripox viruses that lack the ability to efficiently infect cattle were found to carry only one copy of the 27-bp fragment, suggesting that the LSDV126 gene plays an important role in the ability of capripox viruses to infect cattle. In silico analysis of potential antigenic sites in LSDV126 revealed that LSDV126 variants with only one copy of the repeat lack a potentially important antigenic epitope, supporting its possible significance in cattle infection. This study provides new information about the nature of the LSDV126 gene and its possible role in the life cycle of LSDV.


Assuntos
Doença Nodular Cutânea/virologia , Vírus da Doença Nodular Cutânea/imunologia , Proteínas Virais/imunologia , Sequência de Aminoácidos , Animais , Sequência de Bases , Bovinos , Mapeamento de Epitopos , Dosagem de Genes , Doença Nodular Cutânea/diagnóstico , Vírus da Doença Nodular Cutânea/química , Vírus da Doença Nodular Cutânea/genética , Dados de Sequência Molecular , Filogenia , Alinhamento de Sequência , Proteínas Virais/química , Proteínas Virais/genética
7.
J Agric Food Chem ; 67(26): 7466-7474, 2019 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-31184886

RESUMO

The ZMM28 protein encoded by the zmm28 gene is endogenous to maize. DP202216 maize was genetically modified to increase and extend expression of the zmm28 gene relative to native zmm28 gene expression, resulting in plants with enhanced grain yield potential. Evaluation of the history of safe use (HOSU) is one component of the safety assessment framework for a newly expressed protein in a GM crop. The deduced amino acid sequence of the introduced ZMM28 protein in DP202216 maize is identical to the ZMM28 protein in nonmodified conventional maize. The ZMM28 protein has also been found in selected varieties of sweet corn kernels, and closely related proteins are found in other commonly consumed food crops. Concentrations of the ZMM28 protein in event DP202216 maize, conventional maize, and sweet corn are reported. This information supports, in part, the evaluation of HOSU, which can be leveraged in the safety assessment of the ZMM28 protein. Additional studies will be considered in the food and feed safety assessment of the DP202216 maize event.


Assuntos
Proteínas de Plantas/química , Plantas Geneticamente Modificadas/química , Zea mays/química , Sequência de Aminoácidos , Qualidade de Produtos para o Consumidor , Inocuidade dos Alimentos , Alimentos Geneticamente Modificados , Humanos , Dados de Sequência Molecular , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/metabolismo , Alinhamento de Sequência , Zea mays/genética , Zea mays/metabolismo
8.
Zhonghua Yu Fang Yi Xue Za Zhi ; 53(4): 415-418, 2019 Apr 06.
Artigo em Chinês | MEDLINE | ID: mdl-30982279

RESUMO

To study the epidemiology and etiology characteristics of first imported Chikungunya fever case in Henan province, China, 2017. The patient was confirmed by Chikungunya virus (CHIKV) infected as CHIKV ribonucleotide was continuously detected in his serum specimens. BHK-21 cell line was used for virus isolation, the strain was named CHIKV/Henan001/2017. CHIKV/Henan001/2017 belonged to genotype ECSA. The highest ribonucleotide homology sequence of highly conserved region E1 with CHIKV/Henan001/2017 was hk02 strain (99.8%), who was an imported strain to Hong Kong, China, 2016. Epidemiological information and laboratory testing confirmed it was an imported Chikungunya fever case in Henan province, 2017. No secondary case has been reported.


Assuntos
Febre de Chikungunya/epidemiologia , Vírus Chikungunya/genética , Vírus Chikungunya/isolamento & purificação , RNA Viral/genética , Febre de Chikungunya/diagnóstico , Vírus Chikungunya/classificação , China/epidemiologia , Genótipo , Humanos , Epidemiologia Molecular , Dados de Sequência Molecular , Filogenia , Viagem , Proteínas Virais/genética
9.
Molecules ; 24(8)2019 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-31027295

RESUMO

In cells, thymidylate synthases provide the only de novo source of 2'-deoxythymidine-5'-monophosphate (dTMP), required for DNA synthesis. The activity of these enzymes is pivotal for cell survival and proliferation. Two main families of thymidylate synthases have been identified in bacteria, folate-dependent thymidylate synthase (TS) and flavin-dependent TS (FDTS). TS and FDTS are highly divergent enzymes, characterized by exclusive catalytic mechanisms, involving different sets of cofactors. TS and FDTS mechanisms of action have been recently revised, providing new perspectives for the development of antibacterial drugs targeting these enzymes. Nonetheless, some catalytic details still remain elusive. For bacterial TSs, half-site reactivity is still an open debate and the recent evidences are somehow controversial. Furthermore, different behaviors have been identified among bacterial TSs, compromising the definition of common mechanisms. Moreover, the redox reaction responsible for the regeneration of reduced flavin in FDTSs is not completely clarified. This review describes the recent advances in the structural and functional characterization of bacterial TSs and FDTSs and the current understanding of their mechanisms of action. Furthermore, the recent progresses in the development of inhibitors targeting TS and FDTS in human pathogenic bacteria are summarized.


Assuntos
Metiltransferases/metabolismo , Timidilato Sintase/metabolismo , Sequência de Aminoácidos , Flavinas/metabolismo , Humanos , Dados de Sequência Molecular , Estrutura Secundária de Proteína
10.
J Agric Food Chem ; 67(19): 5587-5595, 2019 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-31016980

RESUMO

Maltooligosyltrehalose synthase (MTSase) is a key enzyme in trehalose production. MTSase from Arthrobacter ramosus has poor thermostability, limiting its industrial use. In this study, mutant G415P was obtained by directed evolution and S361R/S444E was subsequently generated based on a structure analysis of the region around G415. The t1/2 of G415P and S361R/S444E at 60 °C increased by 3.0- and 3.2-fold, respectively, compared with the wild-type enzyme. A triple mutant (G415P/S361R/S444E) was obtained through a combination of the above mutants, and its t1/2 significantly increased by 19.7-fold. Kinetic and thermodynamic stability results showed that the T50 and Tm values of the triple mutant increased by 7.1 and 7.3 °C, respectively, compared with those of the wild-type enzyme. When the triple mutant was used in trehalose production, the yield reached 71.6%, higher than the 70.3% achieved with the wild-type. Thus, the mutant has a potential application for industrial trehalose production.


Assuntos
Arthrobacter/enzimologia , Proteínas de Bactérias/química , Proteínas de Bactérias/genética , Glucosiltransferases/química , Glucosiltransferases/genética , Sequência de Aminoácidos , Arthrobacter/química , Arthrobacter/genética , Proteínas de Bactérias/metabolismo , Evolução Molecular Direcionada , Estabilidade Enzimática , Glucosiltransferases/metabolismo , Temperatura Alta , Cinética , Modelos Moleculares , Dados de Sequência Molecular , Mutagênese Sítio-Dirigida , Alinhamento de Sequência , Especificidade por Substrato
11.
J Agric Food Chem ; 67(17): 4958-4966, 2019 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-30966750

RESUMO

The mud crab ( Scylla paramamosain) is widely consumed but can cause a severe food allergic reaction. To reduce allergenicity to arginine kinase (AK), site-directed mutagenesis was used to destroy disulfide bonds or mutate critical amino acids of conformational epitopes. Three hypoallergenic mutant AKs (mAK1, mAK2, and mAK3) were generated, with the immunoreactivity decreasing by 54.2, 40.1, and 71.4%, respectively. In comparison to recombinant AK (rAK), the structure of mAKs was clearly changed. Additionally, antisense peptides were designed on the basis of linear epitopes and pepsin-cutting sites of AK. Five peptide aptamers were screened by molecular docking and then analyzed by the immunoglobulin E inhibition enzyme-linked immunosorbent assay and human Laboratory of Allergic Diseases 2 mast cell degranulation assay. The peptide aptamers could significantly inhibit allergenicity of rAK and mAKs, and the inhibitory effect of peptide aptamer 3 was slightly better than the others. These results provide synergistic methods to reduce allergenicity to AK, which could be applied to other shellfish allergens.


Assuntos
Aptâmeros de Peptídeos/genética , Arginina Quinase/genética , Arginina Quinase/imunologia , Proteínas de Artrópodes/genética , Proteínas de Artrópodes/imunologia , Braquiúros/imunologia , Hipersensibilidade a Frutos do Mar/imunologia , Adolescente , Adulto , Alérgenos/química , Alérgenos/genética , Alérgenos/imunologia , Sequência de Aminoácidos , Animais , Aptâmeros de Peptídeos/imunologia , Arginina Quinase/química , Proteínas de Artrópodes/química , Braquiúros/enzimologia , Braquiúros/genética , Epitopos/química , Epitopos/genética , Epitopos/imunologia , Feminino , Humanos , Imunoglobulina E/imunologia , Masculino , Simulação de Acoplamento Molecular , Dados de Sequência Molecular , Mutagênese Sítio-Dirigida , Adulto Jovem
12.
J Agric Food Chem ; 67(16): 4425-4434, 2019 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-30945860

RESUMO

Grapholita molesta is a notorious fruit borer globally, causing severe damage to fruit production. To control the pest, one commonly used mean is pheromone-mediated management. As an important sex pheromone, Z-8-dodecenyl acetate (Z8-12: Ac), is often coformulated with other active ingredients to regulate the behavior of G. molesta. To uncover its interactions with G. molesta pheromone binding protein 2 (GmolPBP2) is used to help develop insect attractants. During 200 ns molecular dynamics simulations, two representative conformations of the GmolPBP2-Z8-12: Ac complex are selected. Conformation II at the time of 14-106 ns is dominantly maintained by the hydrophobic interactions and hydrogen bond. In Conformation I, which lasts from 106 to 200 ns, the hydrophobic interactions are enhanced while the hydrogen bond is quite weakened, due to the formation of a more sophisticated hydrophobic binding pocket and the enlargement of hydrogen bond distance. Taking the two conformations as a whole, the affinity between GmolPBP2 and Z8-12: Ac is crucially determined by three hot-spots including Phe11, Trp36, and Ile51. These results would provide a basis for the discovery, optimization, and design of leading compounds potentially active to attract G. molesta.


Assuntos
Proteínas de Transporte/química , Ácidos Graxos Monoinsaturados/química , Proteínas de Insetos/química , Mariposas/metabolismo , Feromônios/química , Sequência de Aminoácidos , Animais , Proteínas de Transporte/genética , Proteínas de Transporte/metabolismo , Ácidos Graxos Monoinsaturados/metabolismo , Feminino , Proteínas de Insetos/genética , Proteínas de Insetos/metabolismo , Cinética , Masculino , Dados de Sequência Molecular , Mariposas/química , Mariposas/genética , Feromônios/metabolismo , Ligação Proteica , Alinhamento de Sequência
13.
Pestic Biochem Physiol ; 156: 72-79, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31027583

RESUMO

Metalloenzyme SODs play important roles in insects dealing with environmental stress. Here, we cloned the Cu/ZnSOD (LdCZS) and MnSOD (LdMS) mRNA of Lymantria dispar by rapid amplification of cDNA ends (RACE). Afterwards their expression patterns were detected by quantitative real-time polymerase chain reaction (qPCR) after bioinformatic analysis. We found that both LdCZS and LdMS were widely detected in all gypsy moth larvae and all five tissues that we analyzed, and both of them were up-regulated after larvae were fed with avermectin of sublethal concentration and LC10. The LdCZS expression value are always higher than LdMS after treating with avermectin of sublethal concentrations. In addition, temporal expression profile in avermectin treated larvae showed that LdCZS expressed highest at 2nd hour, and LdMS expressed highest at 6th hour. The cuticulas transcribed LdCZS and LdMS significantly higher than heads, fat bodies, Malpighian tubes, and midguts after spraying avermectin of sublethal concentration. These results suggested that both Cu/ZnSOD and MnSOD are important antioxidant enzymes in L. dispar defensing against pesticide stress, and LdCZS always responded rapider and stronger than LdMS.


Assuntos
Ivermectina/análogos & derivados , Larva/metabolismo , Mariposas/metabolismo , Superóxido Dismutase/metabolismo , Sequência de Aminoácidos , Animais , Biologia Computacional , DNA Complementar/genética , Ivermectina/farmacologia , Larva/efeitos dos fármacos , Larva/genética , Dados de Sequência Molecular , Mariposas/efeitos dos fármacos , Mariposas/genética , Praguicidas/farmacologia , Reação em Cadeia da Polimerase , Superóxido Dismutase/química , Superóxido Dismutase/genética
14.
Pestic Biochem Physiol ; 156: 9-28, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31027586

RESUMO

4-Hydroxyphenylpyruvate dioxgenase (HPPD) enzymes from rat and from several plants contained only about a single inhibitor-binding active site per dimer which matched the content of iron in the purified Arabidopsis thaliana and Avena sativa enzymes. The dimeric HPPDs were about 10 fold more catalytically active than the tetrameric P. fluorescens enzyme with kcat/KmHPP values ranging from 0.8 to 2.5 s-1 µM-1. Most were also highly sensitive to herbicides with, for example, Ki values for mesotrione ranging from 25 to 100 pM. Curiously HPPDs from cool climate grasses were much less herbicide-sensitive. When likewise expressed in Nicotinia tabacum, Avena sativa HPPD, Ki value of 11 nM for mesotrione, conferred far greater tolerance to mesotrione (CallistoTM) than did any of the more sensitive HPPDs. Targeted mutagenesis of the Avena HPPD led to the discovery of 4 mutations imparting improved inherent tolerance, defined as the ratio of Ki to KmHPP, by about 16 fold without any loss of catalytic activity. The Nicotinia line with the highest expression of this quadruple mutant exhibited substantial resistance even up to a 3 kg/ha post-emergence application of mesotrione. The maximum observed expression level of heterologous plant HPPDs in tobacco was ca. 0.35% of the total soluble protein whereas the endogenous tobacco HPPD constituted only ca. 0.00075%. At such high expression even HPPDs with impaired catalytic activity could be effective. A quintuple mutant Avena sativa HPPD conferred substantial tolerance across a broad range of HPPD herbicide chemistries despite being only ca. 5 % as catalytically active as the wild type enzyme. Testing various wild type and mutant HPPDs in tobacco revealed that tolerance to field rates of herbicide generally requires about two order of magnitude increases in both inherent herbicide tolerance and expression relative to endogenous levels. This double hurdle may explain why target-site based resistance to HPPD-inhibiting herbicides has been slow to evolve in weeds.


Assuntos
4-Hidroxifenilpiruvato Dioxigenase/metabolismo , Produtos Agrícolas/efeitos dos fármacos , Produtos Agrícolas/enzimologia , Cicloexanonas/farmacologia , Herbicidas/farmacologia , 4-Hidroxifenilpiruvato Dioxigenase/antagonistas & inibidores , Sequência de Aminoácidos , Animais , Arabidopsis/genética , Arabidopsis/metabolismo , Dados de Sequência Molecular , Plantas Daninhas/efeitos dos fármacos , Plantas Daninhas/metabolismo , Ratos , Homologia de Sequência de Aminoácidos
15.
J Agric Food Chem ; 67(13): 3781-3788, 2019 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-30865469

RESUMO

In recent decades, there have been increasing reports of insect resistance in Bacillus thuringiensis (Bt) crops. Alternative use of Cry toxins, with high insecticidal activity and different mechanisms of action, may be an important strategy to manage this resistance. Cry9 protein, with high toxicity to the lepidopteran pests and no cross-resistance with commercial Cry1 proteins, is a valuable relevant resource. A novel insecticidal protein, MP1489, subsequently named as Cry9Cb1, with 88% amino acid sequence identity with Cry9Ca1, was identified from Bt strain SP663; it exhibited high insecticidal activity against Plutella xylostella, Ostrinia furnacalis, and Chilo suppressalis and no cross-resistance with Cry1Fa in Ostrinia furnacalis. Its minimal active fragments against Plutella xylostella and Ostrinia furnacalis were identified to be 72T-657V and 68D-655A, respectively; food-safety assessment showed no sequence homology with any known allergen and rapid degradation and inactivation by both heat and the gastrointestinal environment. Therefore, Cry9Cb1 is proposed to have a brilliant prospect as an insecticidal protein in agriculture.


Assuntos
Bacillus thuringiensis/química , Proteínas de Bactérias/toxicidade , Endotoxinas/toxicidade , Proteínas Hemolisinas/toxicidade , Sequência de Aminoácidos , Animais , Bacillus thuringiensis/genética , Bacillus thuringiensis/metabolismo , Proteínas de Bactérias/química , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Endotoxinas/genética , Endotoxinas/metabolismo , Proteínas Hemolisinas/genética , Proteínas Hemolisinas/metabolismo , Dados de Sequência Molecular , Mariposas/efeitos dos fármacos
16.
J Agric Food Chem ; 67(13): 3565-3574, 2019 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-30866622

RESUMO

Two OBP genes, BodoOBP1 and BodoOBP2, were cloned from Bradysia odoriphaga, a major agricultural pest of Chinese chives. The amino acid sequence alignment of both BodoOBPs showed high similarity. Fluorescence competitive binding assays revealed that both BodoOBPs have a moderate binding affinity to dipropyl trisulfide. Tissue expression profiles indicated that both BodoOBPs are antennae-specific and more abundant in the male antennae than in the female antennae. Developmental expression profile analysis indicated that expression levels of both BodoOBPs were higher in the male adult stage than in the other developmental stages. Both BodoOBPs also showed differential expression in pre- and postmating adults. RNAi assays indicated that ability of dsOBPs-treated males to detect females was significantly reduced compared to controls. Attraction of plant volatile dipropyl trisulfide to dsOBPs-treated adults was also significantly lower than in the control. Our findings indicate that both BodoOBPs are involved in host-seeking behavior and in detecting sex pheromones.


Assuntos
Dípteros/metabolismo , Proteínas de Insetos/genética , Proteínas de Insetos/metabolismo , Receptores Odorantes/genética , Receptores Odorantes/metabolismo , Sequência de Aminoácidos , Animais , Cebolinha-Francesa/parasitologia , Dípteros/química , Dípteros/genética , Dípteros/crescimento & desenvolvimento , Dissulfetos/química , Dissulfetos/metabolismo , Feminino , Proteínas de Insetos/química , Masculino , Dados de Sequência Molecular , Doenças das Plantas/parasitologia , Receptores Odorantes/química , Alinhamento de Sequência
17.
J Agric Food Chem ; 67(10): 2848-2855, 2019 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-30821967

RESUMO

Two versatile UDP-glucosyltransferases, UGT75L25 and UGT75X1, were isolated from Erigeron breviscapus. The enzymes display high sequence identity to flavonoid 7- O-glucosyltransferase from Malus species and cluster to the phylogenetic group L of plant glucosyltransferases, also involved in the formation of hydroxycinnamoyl glucose esters, which are used as bifunctional donors in the glucosylation or acylation of anthocyanins. The enzymes, functionally expressed in Escherichia coli, exhibit broad substrate specificity toward 21 structurally diverse types of phenolic acids, including (hydroxy)cinnamates, vanillic acid, 3-hydroxycoumarin, and 7-hydroxyflavonoids. The catalytic characteristics of UGT75L25 and UGT75X1 were exploited to generate the corresponding acyl-glucose-esters or glucosides with high efficiency. These findings demonstrate the significant potential of acyl-glucose-esters in the further enzymatic synthesis of bioactive anthocyanins.


Assuntos
Erigeron/enzimologia , Glucosiltransferases/metabolismo , Proteínas de Plantas/metabolismo , Sequência de Aminoácidos , Erigeron/química , Erigeron/genética , Ésteres/química , Ésteres/metabolismo , Glucose/química , Glucose/metabolismo , Glucosiltransferases/química , Glucosiltransferases/genética , Dados de Sequência Molecular , Filogenia , Proteínas de Plantas/química , Proteínas de Plantas/genética , Alinhamento de Sequência , Especificidade por Substrato
18.
Nat Commun ; 10(1): 924, 2019 02 25.
Artigo em Inglês | MEDLINE | ID: mdl-30804332

RESUMO

Peptides have gained so much attention in the last decade that they are now part of the main strategies, with small molecules and biologics, for developing new medicines. Despite substantial progress, the successful development of peptides as drugs still requires a number of limitations to be addressed, including short in vivo half-lives and poor membrane permeability. Here, we describe the use of oligourea foldamers as tool to improve the pharmaceutical properties of GLP-1, a 31 amino acid peptide hormone involved in metabolism and glycemic control. Our strategy consists in replacing four consecutive amino acids of GLP-1 by three consecutive ureido residues by capitalizing on the structural resemblance of oligourea and α-peptide helices. The efficacy of the approach is demonstrated with three GLP-1-oligourea hybrids showing prolonged activity in vivo. Our findings should enable the use of oligoureas in other peptides to improve their pharmaceutical properties and may provide new therapeutic applications.


Assuntos
Diabetes Mellitus/tratamento farmacológico , Peptídeo 1 Semelhante ao Glucagon/análogos & derivados , Peptídeo 1 Semelhante ao Glucagon/farmacocinética , Peptídeos/química , Peptídeos/farmacocinética , Sequência de Aminoácidos , Animais , Peptídeo 1 Semelhante ao Glucagon/sangue , Humanos , Cinética , Masculino , Camundongos Endogâmicos C57BL , Modelos Moleculares , Dados de Sequência Molecular , Peptídeos/sangue
19.
World J Microbiol Biotechnol ; 35(2): 34, 2019 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-30706219

RESUMO

In this present study novel endoxylanase producing Bacillus licheniformis DM5 isolated, identified based on 16S rDNA from Garampani hotspring, Assam, India and enzyme was purified. RNA secondary structure predicted the similarity of B. licheniformis DM5 with B. licheniformis ATCC14580. Highest production of xylanase from B. licheniformis DM5 was achieved in the TY medium with cell densities 12 g/l and extracellular protein concentration containing xylanase 400 mg/l. Partially purified extracellular xylanase displayed optimum pH 6.5 and temperature 50 °C. Thermostability of the xylanase at the elevated temperature showed stability between 50 and 60 °C retaining its 99% activity. Kinetic parameters of thermophilic xylanase revealed Km 1.5 ± 0.2 mg/ml, Vmax 2.7 ± 0.2 U/ml and and Kcat 1.8 ± 0.2 s-1 against beechwood xylan but ruled out any exo-acting activity against synthetic pNP-xylopyranoside substrate. Time dependent enzymatic hydrolysis of beechwood xylan and preprocessed agrowaste corncob exhibited the release of xylotriose and xylobiose oligosaccharide (XOS) significantly high. Xylobiose and xylotriose exhibited higher binding affinities with BIAXP transporter protein of probiotic bacteria explaining their easy uptake by the cells. Mixed oligosaccharides also exhibited better prebiotic activity by promoting growth of Bifidobacterium infantis and Lactobacillus delbrueckii. Mixed XOS when tested for their cytotoxicity on Hela cell lines in in vitro MTT assay displayed significant lowering of cell viability after 48 h and 24 h at 100 µg/ml to 60% and 50%, respectively. In contrast, cytotoxicity wasn't observed against normal cervical cell line (VK2/E6E7-ATCC-CRL-2616). Therefore, thermophilic endoxylanase from B. licheniformis DM5 could be attributed for the production of prebiotic and anti-inflammatory XOS from agrowaste.


Assuntos
Bacillus licheniformis/enzimologia , Proteínas de Bactérias/química , Proteínas de Bactérias/metabolismo , Endo-1,4-beta-Xilanases/química , Endo-1,4-beta-Xilanases/metabolismo , Glucuronatos/metabolismo , Oligossacarídeos/metabolismo , Bacillus licheniformis/química , Bacillus licheniformis/genética , Bacillus licheniformis/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/isolamento & purificação , Sequência de Bases , Endo-1,4-beta-Xilanases/genética , Endo-1,4-beta-Xilanases/isolamento & purificação , Estabilidade Enzimática , Glucuronatos/química , Temperatura Alta , Concentração de Íons de Hidrogênio , Hidrólise , Cinética , Dados de Sequência Molecular , Oligossacarídeos/química , Filogenia , Xilanos/química , Xilanos/metabolismo
20.
Arch Virol ; 164(4): 1193-1198, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30739201

RESUMO

Small-ruminant lentivirus (SRLV) infections are widespread in Poland, and circulation of subtypes A1, A12, A13, A16, A17, B1 and B2 has been documented. The aim of this study was to characterize the SRLV strains circulating in sheep and goats in mixed flocks in the Malopolska region, where the highest seroprevalence has been detected. Phylogenetic analysis revealed that most of the isolates from sheep belonged to subtype A13, suggesting that this subtype may be predominant in the Malopolska region. Furthermore, the existence of a new subtype, tentatively designated as A18, was described for the first time. This work extends the current knowledge on the distribution of SRLV subtypes in sheep and goats in Poland and provides further information on the genetic diversity of SRLV. The new data are important for both epidemiological studies and eradication programs and provide insight into the evolution of SRLV.


Assuntos
Doenças das Cabras/virologia , Infecções por Lentivirus/veterinária , Lentivirus/genética , Lentivirus/isolamento & purificação , Doenças dos Ovinos/virologia , Sequência de Aminoácidos , Animais , Produtos do Gene gag/química , Produtos do Gene gag/genética , Cabras , Lentivirus/química , Lentivirus/classificação , Infecções por Lentivirus/virologia , Dados de Sequência Molecular , Filogenia , Polônia , Alinhamento de Sequência , Ovinos
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