RESUMO
Porins form trimers in the outer membrane and help transport nutrients and waste products across the bacterial cell membrane. Porin loops are suitable candidates as display systems due to their high immunogenicity and presentation at the bacterial cell surface. In this study, Salmonella typhi porins (OmpC and OmpF) engineered with the Kennedy peptide from gp41 of HIV were characterised. The chimeric OmpC carrying the Kennedy peptide in loop7 did not trimerise, whereas the chimeric OmpF with the epitope in loop5 formed trimers and also was recognised by the antibodies in the HIV patient serum. The results suggest that chimeric S. typhi OmpF may be taken further as a potential candidate to develop as an epitope display system. Proteins 2017; 85:657-664. © 2016 Wiley Periodicals, Inc.
Assuntos
Proteínas de Bactérias/química , Epitopos/química , Proteína gp41 do Envelope de HIV/química , Porinas/química , Salmonella typhi/genética , Sequência de Aminoácidos , Proteínas de Bactérias/genética , Proteínas de Bactérias/imunologia , Sítios de Ligação , Clonagem Molecular , Epitopos/genética , Epitopos/imunologia , Escherichia coli/genética , Escherichia coli/metabolismo , Expressão Gênica , HIV/genética , HIV/imunologia , Proteína gp41 do Envelope de HIV/genética , Proteína gp41 do Envelope de HIV/imunologia , Infecções por HIV/imunologia , Infecções por HIV/virologia , Humanos , Soros Imunes/química , Biblioteca de Peptídeos , Porinas/genética , Porinas/imunologia , Ligação Proteica , Conformação Proteica em Folha beta , Engenharia de Proteínas , Domínios e Motivos de Interação entre Proteínas , Multimerização Proteica , Proteínas Recombinantes de Fusão/química , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/imunologia , Salmonella typhi/metabolismo , Alinhamento de SequênciaRESUMO
L-Theanine is an amino acid derivative primarily found in tea. It has been reported to promote relaxation and have neuroprotective effects. The present study was designed to investigate the role of oxidative stress and the status of antioxidant system in the management of aluminum chloride (AlCl3) induced brain toxicity in various rat brain regions and further to elucidate the potential role of L-Theanine in alleviating such negative effects. Aluminium administration significantly decreased the level of reduced glutathione and the activities of superoxide dismutase, catalase, glutathione peroxidase, glutathione reductase, Na(+)/K(+) ATPase, Ca(2+) ATPase and Mg(2+) ATPase and increased the level of lipid peroxidation and the activities of alkaline phosphatase, acid phosphatase, alanine transaminase and aspartate transaminase in all the brain regions when compared with control rats. Pre-treatment with L-Theanine at a dose of 200 mg/kg b.w. significantly increased the antioxidant status and activities of membrane bound enzymes and also decreased the level of LPO and the activities of marker enzymes, when compared with aluminium induced rats. Aluminium induction also caused histopathological changes in the cerebral cortex, cerebellum and hippocampus of rat brain which was reverted by pretreatment with L-Theanine. The present study clearly indicates the potential of L-Theanine in counteracting the damage inflicted by aluminium on rat brain regions.
Assuntos
Compostos de Alumínio/toxicidade , Antioxidantes/uso terapêutico , Cerebelo/efeitos dos fármacos , Córtex Cerebral/efeitos dos fármacos , Cloretos/toxicidade , Glutamatos/uso terapêutico , Síndromes Neurotóxicas/prevenção & controle , Cloreto de Alumínio , Animais , Antioxidantes/administração & dosagem , Antioxidantes/metabolismo , Cerebelo/metabolismo , Cerebelo/patologia , Córtex Cerebral/metabolismo , Córtex Cerebral/patologia , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Glutamatos/administração & dosagem , Hipocampo/efeitos dos fármacos , Hipocampo/metabolismo , Hipocampo/patologia , Peroxidação de Lipídeos/efeitos dos fármacos , Masculino , Síndromes Neurotóxicas/etiologia , Síndromes Neurotóxicas/metabolismo , Síndromes Neurotóxicas/patologia , Estresse Oxidativo/efeitos dos fármacos , RatosRESUMO
The coat protein of cardamom mosaic virus (CdMV), a member of the genus Macluravirus, assembles into virus-like particles when expressed in an Escherichia coli expression system. The N and C-termini of the coat protein were engineered with the Kennedy peptide and the 2F5 and 4E10 epitopes of gp41 of HIV. The chimeric proteins reacted with sera from HIV positive persons and also stimulated secretion of cytokines by peripheral blood mononuclear cells from these persons. Thus, a system based on the coat protein of CdMV can be used to display HIV-1 antigens.
Assuntos
Proteínas do Capsídeo/imunologia , Citocinas/metabolismo , Portadores de Fármacos , Epitopos/imunologia , Anticorpos Anti-HIV/sangue , Proteína gp41 do Envelope de HIV/imunologia , Leucócitos Mononucleares/imunologia , Proteínas do Capsídeo/genética , Epitopos/genética , Proteína gp41 do Envelope de HIV/genética , Potyviridae/genética , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/imunologiaRESUMO
Bipartite geminiviruses possess two movement proteins (NSP and MP), which mediate the intra- and intercellular movement. In order to accomplish the transport process the movement proteins interact with viral nucleic acids in a sequence non-specific manner. To investigate the nucleic acid recognition properties of MP of MYMIV-Sb, the protein was expressed in Escherichia coli as a fusion protein with maltose-binding protein (MBP) and purified in native condition. Gel mobility shift assay was employed for analyzing the DNA recognition properties of purified MBP-MP fusion protein. The analyses demonstrated the sequence non-specific binding of MYMIV-Sb MP to both ds and ssDNA and its high affinity for ssDNA. MP of MYMIV-Sb did not show any specificity towards various forms of plasmid DNA but displayed size selection towards linear dsDNA.
Assuntos
Begomovirus/fisiologia , DNA Viral/metabolismo , Glycine max/virologia , Proteínas do Movimento Viral em Plantas/metabolismo , DNA de Cadeia Simples/metabolismo , Ensaio de Desvio de Mobilidade Eletroforética , Escherichia coli/genética , Expressão Gênica , Ligação Proteica , Proteínas Recombinantes de Fusão/biossíntese , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/isolamento & purificação , Proteínas Recombinantes de Fusão/metabolismoRESUMO
Yellow vein mosaic disease is the major limitation in the production of bhendi or okra (Abelmoschus esculentus), an important vegetable crop of India. This disease is caused by a complex consisting of the monopartite begomovirus Bhendi yellow vein mosaic virus (BYVMV, family: Geminiviridae) and a small satellite DNA beta component. BYVMV can systemically infect bhendi upon agroinoculation but produces only mild leaf curling in this host. DNA beta induces typical symptoms of bhendi yellow vein mosaic disease (BYVMD) when co-agroinoculated with the begomovirus to bhendi. The DNA beta component associated with BYVMD has a number of features in common with those reported for ageratum yellow vein disease and cotton leaf curl disease. BYVMV represents a new member of the emerging group of monopartite begomoviruses requiring a satellite component for symptom induction.