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[PMID]:28460054
[Au] Autor:Zhou N; Zhao S; Tian CY
[Ad] Endereço:State Key Laboratory of Desert and Oasis Ecology, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi, China.
[Ti] Título:Effect of halotolerant rhizobacteria isolated from halophytes on the growth of sugar beet (Beta vulgaris L.) under salt stress.
[So] Source:FEMS Microbiol Lett;364(11), 2017 Jun 15.
[Is] ISSN:1574-6968
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Utilization of rhizobacteria that have associated with plant roots in harsh environments could be a feasible strategy to deal with limits to agricultural production caused by soil salinity. Halophytes occur naturally in high-salt environments, and their roots may be associated with promising microbial candidates for promoting growth and salt tolerance in crops. This study aimed to isolate efficient halotolerant plant-growth-promoting rhizobacterial strains from halophytes and evaluate their activity and effects on sugar beet (Beta vulgaris L.) growth under salinity stress. A total of 23 isolates were initially screened for their ability to secrete 1-aminocyclopropane-1-carboxylate deaminase (ACD) as well as other plant-growth-promoting characteristics and subsequently identified by sequencing the 16S rRNA gene. Three isolates, identified as Micrococcus yunnanensis, Planococcus rifietoensis and Variovorax paradoxus, enhanced salt stress tolerance remarkably in sugar beet, resulting in greater seed germination and plant biomass, higher photosynthetic capacity and lower stress-induced ethylene production at different NaCl concentrations (50-125 mM). These results demonstrate that salinity-adapted, ACD-producing bacteria isolated from halophytes could promote sugar beet growth under saline stress conditions.
[Mh] Termos MeSH primário: Alphaproteobacteria/classificação
Beta vulgaris/microbiologia
Raízes de Plantas/microbiologia
Plantas Tolerantes a Sal/microbiologia
Estresse Fisiológico
[Mh] Termos MeSH secundário: Alphaproteobacteria/genética
Alphaproteobacteria/isolamento & purificação
Beta vulgaris/crescimento & desenvolvimento
Biomassa
Carbono-Carbono Liases/metabolismo
Etilenos/metabolismo
Micrococcus/isolamento & purificação
Micrococcus/metabolismo
Bactérias Planococcus/isolamento & purificação
Bactérias Planococcus/metabolismo
RNA Ribossômico 16S/genética
Salinidade
Solo/química
Microbiologia do Solo
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Ethylenes); 0 (RNA, Ribosomal, 16S); 0 (Soil); 91GW059KN7 (ethylene); EC 3.5.99.7 (1-aminocyclopropane-1-carboxylate deaminase); EC 4.1.- (Carbon-Carbon Lyases)
[Em] Mês de entrada:1801
[Cu] Atualização por classe:180108
[Lr] Data última revisão:
180108
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170502
[St] Status:MEDLINE
[do] DOI:10.1093/femsle/fnx091


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[PMID]:28743066
[Au] Autor:Kim JH; Park HJ; Hwang IK; Han JM; Kim DH; Oh CW; Lee JS; Kang JC
[Ad] Endereço:West Sea Fisheries Research Institute, National Institute of Fisheries Science, Incheon, Republic of Korea.
[Ti] Título:Toxic effects of juvenile sablefish, Anoplopoma fimbria by ammonia exposure at different water temperature.
[So] Source:Environ Toxicol Pharmacol;54:169-176, 2017 Sep.
[Is] ISSN:1872-7077
[Cp] País de publicação:Netherlands
[La] Idioma:eng
[Ab] Resumo:Juvenile sablefish, Anoplopoma fimbria (mean length 17.1±2.4cm, and mean weight 75.6±5.7g) were used to evaluate toxic effects on antioxidant systems, immune responses, and stress indicators by ammonia exposure (0, 0.25, 0.75, and 1.25mg/L) at different water temperature (12 and 17°C) in 1 and 2 months. In antioxidant responses, superoxide dismutase (SOD) and catalase (CAT) were significantly increased by ammonia exposure, whereas glutathione (GSH) was decreased. In immune responses, lysozyme and phagocytosis activity were significantly increased by ammonia exposure. In stress indicators, plasma glucose, heat shock protein 70 (HSP 70), and cortisol were significantly increased. At high water temperature (17°C), alterations by ammonia exposure were more distinctly. The results of this study indicated that ammonia exposure can induce toxic effects in the sablefish, and high water temperature can affect the ammonia exposure toxicity.
[Mh] Termos MeSH primário: Amônia/toxicidade
Perciformes
Poluentes Químicos da Água/toxicidade
[Mh] Termos MeSH secundário: Animais
Catalase/metabolismo
Proteínas de Peixes/metabolismo
Brânquias/efeitos dos fármacos
Brânquias/metabolismo
Glutationa/metabolismo
Proteínas de Choque Térmico HSP70/metabolismo
Hidrocortisona/sangue
Rim/efeitos dos fármacos
Rim/metabolismo
Fígado/efeitos dos fármacos
Fígado/metabolismo
Micrococcus
Muramidase/sangue
Muramidase/metabolismo
Perciformes/sangue
Perciformes/imunologia
Perciformes/metabolismo
Fagocitose
Superóxido Dismutase/metabolismo
Temperatura Ambiente
Água
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Fish Proteins); 0 (HSP70 Heat-Shock Proteins); 0 (Water Pollutants, Chemical); 059QF0KO0R (Water); 7664-41-7 (Ammonia); EC 1.11.1.6 (Catalase); EC 1.15.1.1 (Superoxide Dismutase); EC 3.2.1.17 (Muramidase); GAN16C9B8O (Glutathione); WI4X0X7BPJ (Hydrocortisone)
[Em] Mês de entrada:1711
[Cu] Atualização por classe:171130
[Lr] Data última revisão:
171130
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170726
[St] Status:MEDLINE


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[PMID]:28734213
[Au] Autor:Rojjanateeranaj P; Sangthong C; Prapagdee B
[Ad] Endereço:Laboratory of Environmental Biotechnology, Faculty of Environment and Resource Studies, Mahidol University, Salaya, Nakhonpathom 73170, Thailand.
[Ti] Título:Enhanced cadmium phytoremediation of Glycine max L. through bioaugmentation of cadmium-resistant bacteria assisted by biostimulation.
[So] Source:Chemosphere;185:764-771, 2017 Oct.
[Is] ISSN:1879-1298
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:This study examined the potential of three strains of cadmium-resistant bacteria, including Micrococcus sp., Pseudomonas sp. and Arthrobacter sp., to promote root elongation of Glycine max L. seedlings, soil cadmium solubility and cadmium phytoremediation in G. max L. planted in soil highly polluted with cadmium with and without nutrient biostimulation. Micrococcus sp. promoted root length in G. max L. seedlings under toxic cadmium conditions. Soil inoculation with Arthrobacter sp. increased the bioavailable fraction of soil cadmium, particularly in soil amended with a C:N ratio of 20:1. Pot culture experiments observed that the highest plant growth was in Micrococcus sp.-inoculated plants with nutrient biostimulation. Cadmium accumulation in the roots, stems and leaves of G. max L. was significantly enhanced by Arthrobacter sp. with nutrient biostimulation. A combined use of G. max L. and Arthrobacter sp. with nutrient biostimulation accelerated cadmium phytoremediation. In addition, cadmium was retained in roots more than in stems and leaves and G. max L. had the lowest translocation factor at all growth stages, suggesting that G. max L. is a phytostabilizing plant. We concluded that biostimulation-assisted bioaugmentation is an important strategy for improving cadmium phytoremediation efficiency.
[Mh] Termos MeSH primário: Biodegradação Ambiental
Cádmio/metabolismo
Microbiologia do Solo
Poluentes do Solo/metabolismo
Feijão de Soja/metabolismo
[Mh] Termos MeSH secundário: Arthrobacter
Cádmio/análise
Micrococcus
Desenvolvimento Vegetal
Raízes de Plantas/crescimento & desenvolvimento
Pseudomonas
Plântulas/química
Solo
Poluentes do Solo/análise
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Soil); 0 (Soil Pollutants); 00BH33GNGH (Cadmium)
[Em] Mês de entrada:1710
[Cu] Atualização por classe:171116
[Lr] Data última revisão:
171116
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170723
[St] Status:MEDLINE


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[PMID]:28708872
[Au] Autor:Chonmaitree T; Jennings K; Golovko G; Khanipov K; Pimenova M; Patel JA; McCormick DP; Loeffelholz MJ; Fofanov Y
[Ad] Endereço:Department of Pediatrics, University of Texas Medical Branch, Galveston, TX, United States of America.
[Ti] Título:Nasopharyngeal microbiota in infants and changes during viral upper respiratory tract infection and acute otitis media.
[So] Source:PLoS One;12(7):e0180630, 2017.
[Is] ISSN:1932-6203
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:BACKGROUND: Interferences between pathogenic bacteria and specific commensals are known. We determined the interactions between nasopharyngeal microbial pathogens and commensals during viral upper respiratory tract infection (URI) and acute otitis media (AOM) in infants. METHODS: We analyzed 971 specimens collected monthly and during URI and AOM episodes from 139 infants. The 16S rRNA V4 gene regions were sequenced on the Illumina MiSeq platform. RESULTS: Among the high abundant genus-level nasopharyngeal microbiota were Moraxella, Haemophilus, and Streptococcus (3 otopathogen genera), Corynebacterium, Dolosigranulum, Staphylococcus, Acinetobacter, Pseudomonas, and Bifidobacterium. Bacterial diversity was lower in culture-positive samples for Streptococcus pneumoniae, and Haemophilus influenzae, compared to cultured-negative samples. URI frequencies were positively associated with increasing trend in otopathogen colonization. AOM frequencies were associated with decreasing trend in Micrococcus colonization. During URI and AOM, there were increases in abundance of otopathogen genera and decreases in Pseudomonas, Myroides, Yersinia, and Sphingomonas. Otopathogen abundance was increased during symptomatic viral infection, but not during asymptomatic infection. The risk for AOM complicating URI was reduced by increased abundance of Staphylococcus and Sphingobium. CONCLUSION: Otopathogen genera played the key roles in URI and AOM occurrences. Staphylococcus counteracts otopathogens thus Staphylococcal colonization may be beneficial, rather than harmful. While Sphingobium may play a role in preventing AOM complicating URI, the commonly used probiotic Bifidobacterium did not play a significant role during URI or AOM. The role of less common commensals in counteracting the deleterious effects of otopathogens requires further studies.
[Mh] Termos MeSH primário: Microbiota
Nasofaringe/microbiologia
Otite Média/diagnóstico
Infecções Respiratórias/diagnóstico
Viroses/diagnóstico
[Mh] Termos MeSH secundário: Doença Aguda
Antibacterianos/farmacologia
Antibacterianos/uso terapêutico
Bactérias/classificação
Bactérias/isolamento & purificação
Feminino
Haemophilus influenzae/isolamento & purificação
Seres Humanos
Recém-Nascido
Estudos Longitudinais
Masculino
Microbiota/efeitos dos fármacos
Micrococcus/isolamento & purificação
Otite Média/complicações
Otite Média/tratamento farmacológico
Otite Média/microbiologia
Estudos Prospectivos
RNA Ribossômico 16S/química
RNA Ribossômico 16S/isolamento & purificação
RNA Ribossômico 16S/metabolismo
Infecções Respiratórias/complicações
Infecções Respiratórias/virologia
Fatores de Risco
Análise de Sequência de DNA
Streptococcus pneumoniae/isolamento & purificação
Viroses/complicações
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Anti-Bacterial Agents); 0 (RNA, Ribosomal, 16S)
[Em] Mês de entrada:1709
[Cu] Atualização por classe:170926
[Lr] Data última revisão:
170926
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170715
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pone.0180630


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[PMID]:28603981
[Au] Autor:Hsieh CH; Huang X; Amaya JA; Rutland CD; Keys CL; Groves JT; Austin RN; Makris TM
[Ad] Endereço:Department of Chemistry and Biochemistry, University of South Carolina , Columbia, South Carolina 29208, United States.
[Ti] Título:The Enigmatic P450 Decarboxylase OleT Is Capable of, but Evolved To Frustrate, Oxygen Rebound Chemistry.
[So] Source:Biochemistry;56(26):3347-3357, 2017 Jul 05.
[Is] ISSN:1520-4995
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:OleT is a cytochrome P450 enzyme that catalyzes the removal of carbon dioxide from variable chain length fatty acids to form 1-alkenes. In this work, we examine the binding and metabolic profile of OleT with shorter chain length (n ≤ 12) fatty acids that can form liquid transportation fuels. Transient kinetics and product analyses confirm that OleT capably activates hydrogen peroxide with shorter substrates to form the high-valent intermediate Compound I and largely performs C-C bond scission. However, the enzyme also produces fatty alcohol side products using the high-valent iron oxo chemistry commonly associated with insertion of oxygen into hydrocarbons. When presented with a short chain fatty acid that can initiate the formation of Compound I, OleT oxidizes the diagnostic probe molecules norcarane and methylcyclopropane in a manner that is reminiscent of reactions of many CYP hydroxylases with radical clock substrates. These data are consistent with a decarboxylation mechanism in which Compound I abstracts a substrate hydrogen atom in the initial step. Positioning of the incipient substrate radical is a crucial element in controlling the efficiency of activated OH rebound.
[Mh] Termos MeSH primário: Proteínas de Bactérias/metabolismo
Caproatos/metabolismo
Caprilatos/metabolismo
Sistema Enzimático do Citocromo P-450/metabolismo
Ácidos Decanoicos/metabolismo
Ácidos Láuricos/metabolismo
Micrococcus/enzimologia
Modelos Moleculares
[Mh] Termos MeSH secundário: Proteínas de Bactérias/química
Proteínas de Bactérias/genética
Biocatálise
Biocombustíveis/análise
Caprilatos/química
Carboxiliases/química
Carboxiliases/genética
Carboxiliases/metabolismo
Domínio Catalítico
Ciclopropanos/química
Ciclopropanos/metabolismo
Sistema Enzimático do Citocromo P-450/química
Sistema Enzimático do Citocromo P-450/genética
Ácidos Decanoicos/química
Descarboxilação
Guaiacol/metabolismo
Peróxido de Hidrogênio/química
Peróxido de Hidrogênio/metabolismo
Ácidos Láuricos/química
Conformação Molecular
Oxirredução
Especificidade por Substrato
Terpenos/química
Terpenos/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Bacterial Proteins); 0 (Biofuels); 0 (Caproates); 0 (Caprylates); 0 (Cyclopropanes); 0 (Decanoic Acids); 0 (Lauric Acids); 0 (Terpenes); 1F8SN134MX (hexanoic acid); 4G9EDB6V73 (decanoic acid); 594-11-6 (1-methylcyclopropane); 6JKA7MAH9C (Guaiacol); 9035-51-2 (Cytochrome P-450 Enzyme System); BBX060AN9V (Hydrogen Peroxide); EC 4.1.1.- (Carboxy-Lyases); OBL58JN025 (octanoic acid); ZGC3T0R48Q (norcarane)
[Em] Mês de entrada:1707
[Cu] Atualização por classe:171029
[Lr] Data última revisão:
171029
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170613
[St] Status:MEDLINE
[do] DOI:10.1021/acs.biochem.7b00338


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[PMID]:28414782
[Au] Autor:Arrigucci R; Pozzi G
[Ad] Endereço:Public Health Research Institute, Rutgers, The State University of New Jersey, Newark, NJ, United States of America.
[Ti] Título:Identification of the chain-dispersing peptidoglycan hydrolase LytB of Streptococcus gordonii.
[So] Source:PLoS One;12(4):e0176117, 2017.
[Is] ISSN:1932-6203
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Bacterial cell division ends with the separation of the daughter cells, a process that requires peptidoglycan hydrolases (PGHs). Bacteria lacking cell separating PGHs are impaired in cell separation with the formation of long chains or clusters. We identified a gene in Streptococcus gordonii encoding for a putative glucosaminidase (lytB). The lytB isogenic mutant grew in long bacterial chains and resulted in impaired biofilm formation. Purified recombinant LytB showed a murolytic activity on Micrococcus lysodeikticus cell suspension and was able to disperse the long chains of the mutant, restoring the wild type diplococci/short chain phenotype. LytB protein was localized only in culture supernatant cell fraction of S. gordonii, and co-cultures of wild type and lytB mutant showed a significant reduction of bacterial chain length, indicating that LytB is a secreted enzyme. Our results demonstrate that LytB is a secreted peptidoglycan hydrolase required for S. gordonii cell separation.
[Mh] Termos MeSH primário: Proteínas de Bactérias/genética
N-Acetil-Muramil-L-Alanina Amidase/genética
Peptidoglicano/genética
Streptococcus gordonii/genética
[Mh] Termos MeSH secundário: Biofilmes
Divisão Celular/genética
Técnicas de Cocultura/métodos
Micrococcus/genética
Mutação/genética
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Bacterial Proteins); 0 (Peptidoglycan); EC 3.5.1.- (LytB protein, Streptococcus); EC 3.5.1.28 (N-Acetylmuramoyl-L-alanine Amidase)
[Em] Mês de entrada:1704
[Cu] Atualização por classe:170505
[Lr] Data última revisão:
170505
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170418
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pone.0176117


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[PMID]:28238861
[Au] Autor:Jiang J; Zhou Z; Dong Y; Gao S; Sun H; Chen Z; Yang A; Su H
[Ad] Endereço:Liaoning Key Lab of Marine Fishery Molecular Biology, Liaoning Ocean and Fisheries Science Research Institute, Dalian, Liaoning 116023, PR China.
[Ti] Título:Comparative analysis of immunocompetence between females and males in the sea cucumber Apostichopus japonicus.
[So] Source:Fish Shellfish Immunol;63:438-443, 2017 Apr.
[Is] ISSN:1095-9947
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:In order to preliminarily understand the immune difference between females and males in the sea cucumber Apostichopus japonicus, the activities assay of superoxide dismutase (SOD), catalase (CAT), peroxidase (POD), phenoloxidase (PO), acid phosphatase (ACP) and alkaline phosphatase (ALP) with biochemical methods, the detection of PO isozymes with native-PAGE and catechol staining, and the test of antibacterial activities with bacterial growth curve determination method were performed in this study using cell-free coelomic fluid (CCF) and coelomocyte lysate supernatant (CLS) from females and males as the samples. The PO activities were not detected in the CLS and showed no significant difference between the CCF from females and males. However, totally five PO isozyme bands were detected in the CLS of females while only four were detected in the CLS of males after zymogram analysis. These results implied that the PO isozymes in the coelomocytes of viripotent A. japonicus were inactive under natural condition and may be activated by some certain treatments during native-PAGE, and PO might play different immune and physiological roles between females and males. In addition, the activities of SOD, CAT, POD and ALP in the CCF and the activities of CAT, POD, ACP and ALP in the CLS from males were all significantly higher than those from females. The results collectively suggested that in viripotent A. japonicus, the gender had a remarkable effect on the immunity, and the immunocompetence of males might have an advantage over that of females. Furthermore, the activities of all determined enzymes except PO and the number of detected PO isozymes showed higher values in CLS than in CCF, implying that in viripotent A. japonicus, the coelomocytes might take more immune responsibility in comparison with CCF.
[Mh] Termos MeSH primário: Imunocompetência
Micrococcus/fisiologia
Stichopus/imunologia
[Mh] Termos MeSH secundário: Animais
Feminino
Masculino
Fatores Sexuais
Stichopus/enzimologia
Stichopus/microbiologia
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Em] Mês de entrada:1705
[Cu] Atualização por classe:170501
[Lr] Data última revisão:
170501
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170228
[St] Status:MEDLINE


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[PMID]:28109904
[Au] Autor:Kirschman LJ; Quade AH; Zera AJ; Warne RW
[Ad] Endereço:Department of Zoology, Southern Illinois University, Carbondale, IL, USA. Electronic address: l.j.kirschman@siu.edu.
[Ti] Título:Immune function trade-offs in response to parasite threats.
[So] Source:J Insect Physiol;98:199-204, 2017 Apr.
[Is] ISSN:1879-1611
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Immune function is often involved in physiological trade-offs because of the energetic costs of maintaining constitutive immunity and mounting responses to infection. However, immune function is a collection of discrete immunity factors and animals should allocate towards factors that combat the parasite threat with the highest fitness cost. For example, animals on dispersal fronts of expanding population may be released from density-dependent diseases. The costs of immunity, however, and life history trade-offs in general, are often context dependent. Trade-offs are often most apparent under conditions of unusually limited resources or when animals are particularly stressed, because the stress response can shift priorities. In this study we tested how humoral and cellular immune factors vary between phenotypes of a wing dimorphic cricket and how physiological stress influences these immune factors. We measured constitutive lysozyme activity, a humoral immune factor, and encapsulation response, a cellular immune factor. We also stressed the crickets with a sham predator in a full factorial design. We found that immune strategy could be explained by the selective pressures encountered by each morph and that stress decreased encapsulation, but not lysozyme activity. These results suggest a possible trade-off between humoral and cellular immunity. Given limited resources and the expense of immune factors, parasite pressures could play a key factor in maintaining insect polyphenism via disruptive selection.
[Mh] Termos MeSH primário: Gryllidae/imunologia
Imunidade Celular
Imunidade Humoral
Micrococcus/fisiologia
Asas de Animais/anatomia & histologia
[Mh] Termos MeSH secundário: Animais
Feminino
Gryllidae/anatomia & histologia
Gryllidae/enzimologia
Gryllidae/microbiologia
Muramidase/metabolismo
Fenótipo
Estresse Fisiológico
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
EC 3.2.1.17 (Muramidase)
[Em] Mês de entrada:1707
[Cu] Atualização por classe:170714
[Lr] Data última revisão:
170714
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170123
[St] Status:MEDLINE


  9 / 3971 MEDLINE  
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[PMID]:27858137
[Au] Autor:Miao LL; Fan HX; Qu J; Liu Y; Liu ZP
[Ad] Endereço:State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, No. 1 West Beichen Road, Chaoyang District, Beijing, 100101, People's Republic of China.
[Ti] Título:Specific amino acids responsible for the cold adaptedness of Micrococcus antarcticus ß-glucosidase BglU.
[So] Source:Appl Microbiol Biotechnol;101(5):2033-2041, 2017 Mar.
[Is] ISSN:1432-0614
[Cp] País de publicação:Germany
[La] Idioma:eng
[Ab] Resumo:Psychrophilic enzymes display efficient activity at moderate or low temperatures (4-25 °C) and are therefore of great interest in biotechnological industries. We previously examined the crystal structure of BglU, a psychrophilic ß-glucosidase from the bacterium Micrococcus antarcticus, at 2.2 Å resolution. In structural comparison and sequence alignment with mesophilic (BglB) and thermophilic (GlyTn) counterpart enzymes, BglU showed much lower contents of Pro residue and of charged amino acids (particularly positively charged) on the accessible surface area. In the present study, we investigated the roles of specific amino acid residues in the cold adaptedness of BglU. Mutagenesis assays showed that the mutations G261R and Q448P increased optimal temperature (from 25 to 40-45 °C) at the expense of low-temperature activity, but had no notable effects on maximal activity or heat lability. Mutations A368P, T383P, and A389E significantly increased optimal temperature (from 25 to 35-40 °C) and maximal activity (~1.5-fold relative to BglU). Thermostability of A368P and A389E increased slightly at 30 °C. Mutations K163P, N228P, and H301A greatly reduced enzymatic activity-almost completely in the case of H301A. Low contents of Pro, Arg, and Glu are important factors contributing to BglU's psychrophilic properties. Our findings will be useful in structure-based engineering of psychrophilic enzymes and in production of mutants suitable for a variety of industrial processes (e.g., food production, sewage treatment) at cold or moderate temperatures.
[Mh] Termos MeSH primário: Adaptação Fisiológica/genética
Proteínas de Bactérias/genética
Micrococcus/enzimologia
Micrococcus/metabolismo
beta-Glucosidase/genética
beta-Glucosidase/metabolismo
[Mh] Termos MeSH secundário: Sequência de Aminoácidos
Aminoácidos/genética
Proteínas de Bactérias/metabolismo
Temperatura Baixa
Estabilidade Enzimática
Micrococcus/genética
Mutagênese Sítio-Dirigida
Conformação Proteica
Alinhamento de Sequência
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Amino Acids); 0 (Bacterial Proteins); EC 3.2.1.21 (beta-Glucosidase)
[Em] Mês de entrada:1702
[Cu] Atualização por classe:170227
[Lr] Data última revisão:
170227
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:161119
[St] Status:MEDLINE
[do] DOI:10.1007/s00253-016-7990-x


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[PMID]:27836723
[Au] Autor:Liu Y; Sun Y; Wang Q; Hou F; Liu X
[Ad] Endereço:College of Animal Science and Technology, Northwest A&F University, Shaanxi, Yangling 712100, China.
[Ti] Título:Identification and functional characterizations of serpin8, a potential prophenoloxidase-activating protease inhibitor in Pacific white shrimp, Litopenaeus vannamei.
[So] Source:Fish Shellfish Immunol;60:492-501, 2017 Jan.
[Is] ISSN:1095-9947
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Serpins have been characterized from varieties of organisms by their inhibitory roles on serine or cysteine proteases. However, research for the functional study of serpins in crustacean is relatively small. To fully clarify the immune characterizations of serpin, a novel serpin (named Lvserpin8) encoding 414 amino acids with a 19-amino acid signal peptide and a serpin domain was identified from the Pacific white shrimp Litopenaeus vannamei. Sequence analysis indicated that the genomic Lvserpin8 gene contains 5 exons and 4 introns. The P1 residues of the predicted scissile bond in the reactive center loop (RCL) region represented for Lysine (Lys), which is in accordance with Pmserpin8, Dmserpin27A, Ofserpin3, Bmserpin3 and Msserpin3. Quantitative results showed that high mRNA expression of Lvserpin8 was detected in hepatopancreas and testis. Notably, a significant increase of Lvserpin8 was appeared post injection of Vibrio anguillarum, and Micrococcus lysodeikticus. Moreover, Lvserpin8 was knocked down in vivo by double-stranded RNA (dsRNA) mediated RNA interference (RNAi). Suppression of Lvserpin8 led to a significant increase in the transcripts of LvPPAE2 (Prophenoloxidase-activating Enzyme 2) and cumulative mortality. What's more, recombinant Lvserpin8 protein (rLvserpin8) displayed inhibition roles on trypsin activity, and prophenoloxidase activation. Taken together, the results implied that Lvserpin8 may be involved in shrimp innate immunity via the inhibition of prophenoloxidase-activating proteases.
[Mh] Termos MeSH primário: Imunidade Inata
Penaeidae/genética
Penaeidae/imunologia
Serpinas/genética
Serpinas/metabolismo
[Mh] Termos MeSH secundário: Sequência de Aminoácidos
Animais
Proteínas de Artrópodes/química
Proteínas de Artrópodes/genética
Proteínas de Artrópodes/metabolismo
Sequência de Bases
Clonagem Molecular
DNA Complementar/genética
DNA Complementar/metabolismo
Micrococcus/fisiologia
Especificidade de Órgãos
Penaeidae/classificação
Penaeidae/microbiologia
Filogenia
RNA de Cadeia Dupla/genética
RNA de Cadeia Dupla/metabolismo
RNA Mensageiro/genética
RNA Mensageiro/metabolismo
Proteínas Recombinantes/genética
Proteínas Recombinantes/metabolismo
Alinhamento de Sequência
Serpinas/química
Serpinas/imunologia
Vibrio/fisiologia
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Arthropod Proteins); 0 (DNA, Complementary); 0 (RNA, Double-Stranded); 0 (RNA, Messenger); 0 (Recombinant Proteins); 0 (Serpins)
[Em] Mês de entrada:1703
[Cu] Atualização por classe:170327
[Lr] Data última revisão:
170327
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:161113
[St] Status:MEDLINE



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