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1.
Biochemistry (Mosc) ; 80(2): 180-201, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25756533

RESUMO

It was shown previously that, as differentiated from canonical proteases, abzymes against myelin basic protein (MBP) from blood of patients with multiple sclerosis and systemic lupus erythematosus effectively cleaved only MBP, while antibodies (ABs) against integrase (IN) from blood of HIV-infected patients specifically hydrolyzed only IN. In this work, all sites of effective hydrolysis by anti-IN antibodies (IgG and IgM) of 25-mer oligopeptide (OP25) corresponding to MBP were identified using reversed-phase and thin-layer chromatographies and MALDI mass spectrometry. It was found that amino acid sequences of OP25 and other oligopeptides hydrolyzed by anti-MBP abzymes were partially homologous to some fragments of the full sequence of IN. Sequences of IN oligopeptides cleavable by anti-IN abzymes were homologous to some fragments of MBP, but anti-MBP abzymes could not effectively hydrolyze OPs corresponding to IN. The common features of the cleavage sites of OP25 and other oligopeptides hydrolyzed by anti-MBP and anti-IN abzymes were revealed. The literature data on hydrolysis of specific and nonspecific proteins and oligopeptides by abzymes against different protein antigens were analyzed. Overall, the literature data suggest that short OPs, including OP25, mainly interact with light chains of polyclonal ABs, which had lower affinity and specificity to the substrate than intact ABs. However, it seems that anti-IN ABs are the only one example of abzymes capable of hydrolyzing various oligopeptides with high efficiency (within some hours but not days). Possible reasons for the efficient hydrolysis of foreign oligopeptides by anti-IN abzymes from HIV-infected patients are discussed.


Assuntos
Anticorpos Catalíticos/metabolismo , Infecções por HIV/imunologia , Integrases/imunologia , Oligopeptídeos/metabolismo , Proteólise , Proteínas Virais/imunologia , Adolescente , Adulto , Anticorpos Catalíticos/imunologia , Cromatografia em Camada Fina , Feminino , Humanos , Imunoglobulina G/imunologia , Imunoglobulina M/imunologia , Integrases/metabolismo , Masculino , Proteínas Virais/metabolismo , Adulto Jovem
2.
Klin Lab Diagn ; 59(8): 22-5, 2014 Aug.
Artigo em Russo | MEDLINE | ID: mdl-25552048

RESUMO

The helminths Opisthorchis felineus, Opisthorchis viverrini, Clonorchis sinensis, Metorchis bilis are the agents of opisthorchiasis. The actual diagnostic of parasitic diseases based on microscope analysis of samples of human feces to detect presence of ova of parasites suffers of many shortcomings, in particular low sensitivity especially at earlier stages. The purpose of this study was to compare results of detection of parasites using both classical technique and technique of specific differentiation based on extraction of nucleic acids from samples of human feces and implementation of reaction of amplification of the chosen fragment of DNA with detection of products of polymerase chain reaction in the real time. The study detected 150 out of 165 positive samples and also 6 out of 37 negative samples both validated by coproovoscopy.


Assuntos
Clonorchis sinensis/isolamento & purificação , DNA Mitocondrial/isolamento & purificação , Opistorquíase/diagnóstico , Opisthorchis/isolamento & purificação , Kit de Reagentes para Diagnóstico , Adulto , Idoso , Animais , Criança , Clonorchis sinensis/genética , Clonorchis sinensis/patogenicidade , DNA Mitocondrial/genética , Fezes/parasitologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Opistorquíase/genética , Opistorquíase/parasitologia , Opisthorchis/genética , Opisthorchis/patogenicidade
3.
Mol Biol (Mosk) ; 40(5): 857-64, 2006.
Artigo em Russo | MEDLINE | ID: mdl-17086987

RESUMO

DNAase activity of 110 samples of IgG from the blood of AIDS patients was analyzed. It was shown that the relative activity of preparations varies very much from patient to patient, but 96% preparations show detectable level of DNAase activity. Several rigid criteria were applied and it was shown that DNAase activity is an intrinsic property of antibodies from AIDS patients. It was shown that catalytic activity could posses not only intact IgG, but also separated light chains of polyclonal antibodies. The abzymes catalyze DNA hydrolysis effectively in a wild range of pH (5.0-9.5). K(M) and V(MaKC) values of antibody-dependent hydrolysis of DNA was estimated.


Assuntos
Síndrome da Imunodeficiência Adquirida/imunologia , Sangue/imunologia , DNA/metabolismo , Imunoglobulina G/metabolismo , Síndrome da Imunodeficiência Adquirida/sangue , Adolescente , Adulto , Anticorpos Catalíticos/imunologia , Anticorpos Catalíticos/metabolismo , Cromatografia de Afinidade/métodos , Humanos , Concentração de Íons de Hidrogênio , Hidrólise , Imunoglobulina G/isolamento & purificação , Cinética
4.
Biochemistry (Mosc) ; 71(3): 251-61, 2006 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16545061

RESUMO

Proteolytic activity of polyclonal IgG antibodies (Abs) from the blood of AIDS patients was analyzed for the first time. These Abs were shown to display higher activity in hydrolysis of beta-casein than in hydrolysis of human immunodeficiency virus (HIV)-1 reverse transcriptase (RT) or human serum albumin (HSA). Several abzymatic criteria were applied and it was shown that RT, HSA, and beta-casein hydrolyzing activities are an intrinsic property of polyclonal Abs from AIDS patients. Casein-hydrolyzing Abs were detected in the blood serum for 95% of AIDS patients, and it was shown that they possess serine protease-like catalytic activity. The substrate specificities of polyclonal Ab proteases and typical human proteases are different. Depending on the patient, the IgGs exhibit various pH optima of proteolytic activity. The products of casein hydrolysis by Ab proteases were different from those in the case of trypsin, chymotrypsin, and proteinase K.


Assuntos
Síndrome da Imunodeficiência Adquirida , Anticorpos Catalíticos , Imunoglobulina G/sangue , Imunoglobulina G/imunologia , Síndrome da Imunodeficiência Adquirida/sangue , Síndrome da Imunodeficiência Adquirida/enzimologia , Síndrome da Imunodeficiência Adquirida/imunologia , Adolescente , Adulto , Animais , Anticorpos Catalíticos/sangue , Anticorpos Catalíticos/imunologia , Caseínas/química , Caseínas/metabolismo , Transcriptase Reversa do HIV/metabolismo , Humanos , Concentração de Íons de Hidrogênio , Imunoglobulina G/isolamento & purificação , Peso Molecular , Albumina Sérica/metabolismo
5.
Nucleosides Nucleotides Nucleic Acids ; 23(6-7): 1053-6, 2004 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-15560102

RESUMO

DNA-hydrolyzing antibodies (DNA-abzymes, Abz) were shown to be good biochemical markers of some autoimmune diseases such as systemic lupus erythematosus (SLE) and multiple sclerosis (MS). To better understand mechanisms of abzyme generation, one needs to know optimal conditions for DNA hydrolysis by DNA-abzymes, as well as their enzymatic properties in comparison with those of enzymes possessing the same activity. In contrast to human urine deoxyribonucleases, DNA-hydrolyzing antibodies efficiently digested both single- and double-strand DNA. It was shown that polyclonal antibodies (Abs) in MS may contain up to several types of DNase activities, either activated by metal ions or not.


Assuntos
Anticorpos Catalíticos/metabolismo , Desoxirribonucleases/metabolismo , Sequência de Bases , Desoxirribonucleases/urina , Eletroforese em Gel de Poliacrilamida , Humanos , Hidrólise , Lúpus Eritematoso Sistêmico/enzimologia , Lúpus Eritematoso Sistêmico/urina , Esclerose Múltipla/enzimologia , Esclerose Múltipla/urina , Especificidade por Substrato
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