Consulta: subjectFacets:"RecA"
Registros recuperados: 5
Data/hora: 10/06/2024 09:21:14

A simple negative selection method to identify adenovirus recombinants using colony PCR
Provedor de dados: Electronic Journal of Biotechnology
Autores: Zhao,Yongliang; Dong,Zongming; Li,Tengfei; Huang,Gang.
Background: The AdEasy system is a fast-track system for generating recombinant adenoviruses using the efficient homologous recombination machinery between shuttle and adenovirus backbone plasmids in Escherichia coli BJ5183 cells. The key step is homologous recombination in BJ5183 cells, which is driven by RecA activity. However, culture time is stringently limited to reduce the damage to recombinant plasmids by RecA activity. Therefore, rapid identification of recombinant adenoviruses within the limited time-period is critical. Results: We developed a simple negative selection method to identify recombinant adenoviruses using colony PCR, which improves the efficiency of adenovirus recombination screening and packaging. Conclusions: The negative selection...
Tipo: Journal article
Palavras-chave: Adenovirus; AdEasy; Colony PCR; Homologous recombination; RecA.
Ano: 2014
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582014000100008

A model for the RecA protein of Mycoplasma synoviae
Provedor de dados: Genetics and Molecular Biology
Autores: Fonseca,Marbella Maria; Alarcon,Frank J.B.; Vasconcelos,Ana Tereza de; Agnez-Lima,Lucymara Fassarela.
In this work, we predict a structural model for the RecA protein from M. synoviae (MsRecA) by theoretical homology modeling and evaluate the occurrence of polymorphisms in this protein within several isolates of this species. The structural model suggested for MsRecA conserves the main domains present in MtRecA and EcRecA. The L1 and L2 regions showed six and three amino acid substitutions, respectively, which apparently do not affect the conformation and function of MsRecA. The C-terminal domain is shorter than that found in EcRecA and MtRecA, which may increase its capacity to bind dsDNA and displace SSB, compensating the absence of recombination initiation enzymes. The MS59 isolate RecA sequence showed one polymorphism which does not affect its...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: DNA repair; Recombination; RecA; Mycoplasma synoviae.
Ano: 2007
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572007000200018

The RecX protein interacts with the RecA protein and modulates its activity in Herbaspirillum seropedicae
Provedor de dados: Brazilian Journal of Medical and Biological Research
Autores: Galvão,C.W.; Souza,E.M.; Etto,R.M.; Pedrosa,F.O.; Chubatsu,L.S.; Yates,M.G.; Schumacher,J.; Buck,M.; Steffens,M.B.R.
DNA repair is crucial to the survival of all organisms. The bacterial RecA protein is a central component in the SOS response and in recombinational and SOS DNA repairs. The RecX protein has been characterized as a negative modulator of RecA activity in many bacteria. The recA and recX genes of Herbaspirillum seropedicae constitute a single operon, and evidence suggests that RecX participates in SOS repair. In the present study, we show that the H. seropedicae RecX protein (RecX Hs) can interact with the H. seropedicaeRecA protein (RecA Hs) and that RecA Hs possesses ATP binding, ATP hydrolyzing and DNA strand exchange activities. RecX Hs inhibited 90% of the RecA Hs DNA strand exchange activity even when present in a 50-fold lower molar concentration than...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: RecA; RecX; Herbaspirillum seropedicae; SOS repair.
Ano: 2012
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X2012001200004

Overexpression of Salmonella enterica serovar Typhi recA gene confers fluoroquinolone resistance in Escherichia coli DH5α
Provedor de dados: Brazilian Journal of Medical and Biological Research
Autores: Yassien,M.A.M.; Elfaky,M.A.
A spontaneous fluoroquinolone-resistant mutant (STM1) was isolated from its parent Salmonella enterica serovar Typhi (S. Typhi) clinical isolate. Unlike its parent isolate, this mutant has selective resistance to fluoroquinolones without any change in its sensitivity to various other antibiotics. DNA gyrase assays revealed that the fluoroquinolone resistance phenotype of the STM1 mutant did not result from alteration of the fluoroquinolone sensitivity of the DNA gyrase isolated from it. To study the mechanism of fluoroquinolone resistance, a genomic library from the STM1 mutant was constructed in Escherichia coli DH5α and two recombinant plasmids were obtained. Only one of these plasmids (STM1-A) conferred the selective fluoroquinolone resistance phenotype...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Salmonella enterica serovar Typhi; Fluoroquinolones; RecA.
Ano: 2015
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X2015001100990

Cloning and high-level expression of Thermus thermophilus RecA in E. coli: purification and novel use in HBV diagnostics
Provedor de dados: Brazilian Journal of Microbiology
Autores: Sundarrajan,Sudarson; Rao,Sneha; Padmanabhan,Sriram.
ABSTRACT We studied the role of Thermus thermophilus Recombinase A (RecA) in enhancing the PCR signals of DNA viruses such as Hepatitis B virus (HBV). The RecA gene of a thermophilic eubacterial strain, T. thermophilus, was cloned and hyperexpressed in Escherichia coli. The recombinant RecA protein was purified using a single heat treatment step without the use of any chromatography steps, and the purified protein (&gt;95%) was found to be active. The purified RecA could enhance the polymerase chain reaction (PCR) signals of HBV and improve the detection limit of the HBV diagnosis by real time PCR. The yield of recombinant RecA was ∼35 mg/L, the highest yield reported for a recombinant RecA to date. RecA can be successfully employed to enhance detection...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: RecA; Hepatitis B virus; DNA virus; Thermus thermophilus.
Ano: 2018
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1517-83822018000400848