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101.
Ligninolytic enzyme complexes are involved in lignin degradation. Among them laccases are outstanding because they use molecular oxygen as a co-substrate instead of hydrogen peroxide as used by peroxidases. Bacterial laccase of Bacillus genus was first reported in Claus and Filip (Microbiol Res 152:209–216, 1997), since then more bacterial laccases have been found. In this research, laccase-producing bacteria were screened from pulp and paper industry wastewater, bagass and sugarcane rhizosphere. Nutrient agar medium containing 0.5 mM of guaiacol was used. It was observed that the laccase-producing strains developed brown colour from which 16 strains of Bacillus were identified. One of the isolated strains was identified as Bacillus subtilis WPI based on the results of biochemical tests and 16S rDNA sequence analysis. This strain showed laccase-like activity towards the oxidizing substrates ABTS and guaiacol. In this study guaiacol was used as the substrate of laccase activity assay. For determination of laccase activity of this isolate guaiacol was used as a substrate of assay for the first time in this study. SDS-PAGE and Native-PAGE confirmed the presence of laccase.  相似文献   
102.
103.

Background:

Allergy is a clinical disorder affecting the human population with wide geographical distribution. Platanus orientalis (P. orientalis) trees are planted in many countries and their pollen causes allergic reactions.Cyclophilin has recently been identified as one of the most important allergens of P. orientalis pollen. We aimed to clone and purify this allergen in Escherichia coli for further studies and therapeutic and diagnostic purposes for allergy to P. orientalis.

Methods:

RNA was extracted from P. orientalis. A full-length fragment encoding cyclophilin was prepared by polymerase chain reaction amplification of the first-strand cDNA synthesized from P. orientalis RNA. The cDNA was inserted into the pET32b (+) vector, and the construct transformed into E. coli Top10 and BL21 cells. The expressed protein was purified by the CuSO4 method.

Results:

The cDNA for the cyclophilin of P. orientalis pollen was cloned, and a specific reactivity of recombinant cyclophin was confirmed by immunoblotting using sera from patients allergic to P. orientalis pollen.

Conclusion:

The recombinant cyclophilin has a potential for immunologic assays for evaluation of allergy to P. orientalis pollen.Key Words: Allergy; Recombinant allergen; Cyclophilin, Escherichia coli, Platanus orientalis, Pollen, Cloning  相似文献   
104.

Background:

DNA immunization with plasmid DNA encoding bacterial, viral, parasitic, and tumor antigens has been reported to trigger protective immunity. The use of plasmid DNA vaccinations against many diseases has produced promising results in animal and human clinical trials; however, safety concerns about the use of DNA vaccines exist, such as the possibility of integration into the host genome, and elicitation of adverse immune responses.

Methods:

In this study, we examined the potential integration and bio-distribution of pcDNA3.1+PA, a new vaccine candidate with GenBank accession # EF550208, encoding the PA63 gene, in reproductive organs of mice; ovaries and uterus in female, and testis in male. Animals of both sexes were injected intramuscularly with pcDNA3.1+PA. Host genome integration and tissue distribution were examined using PCR and RT-PCR two times monthly for six months.

Results:

RT-PCR confirmed that pcDNA3.1+PA was not integrated into the host genome and did not enter reproductive organs.

Conclusions:

This finding has important implications for the use of pcDNA3.1+PA plasmid as a vaccine and opens new perspectives in the DNA vaccine area.Key Words: DNA, Intramuscular injection, Integration, Mice, Reproductive organs  相似文献   
105.
Previously, an extracellular α-amylase (BKA) had been purified from the culture of Bacillus sp. KR8104. Subsequently, the crystal structure of the active enzyme revealed a 422 amino acids polypeptide. In this study, the bka was cloned into E. coli, which encoded a polypeptide of 659 amino acids including two additional fragments: one 44 residues N-terminal fragment and another 193 residues C-terminal fragment. In order to investigate the role of the C-terminal fragment, two constructs with and without this region [BKAΔ(N44) and BKAΔ(N44C193)] were designed and expressed in E. coli BL21. The optimum pH, thermal stability, and the end-products of starch hydrolysis were found to be similar in both constructs. The Km and V(max) values for BKAΔ(N44) were lower than BKAΔ(N44C193), using either starch or ethylidene-blocked 4-nitrophenylmaltoheptaoside as a substrate.  相似文献   
106.
The O-silylation of OH groups of alcohols and phenols with hexamethyldisilazane (HMDS) was achieved in high-to-excellent yields using catalytic quantities of a SBA-15-supported cobalt(II) nanocatalyst (typically 0.5?mol-%) at room temperature and under solvent-free conditions. Furthermore, the heterogeneous catalyst showed an excellent durability and can be conveniently reused by filtration for at least twelve times without any noticeable loss of activity.  相似文献   
107.
In the present study, water extract of dried fruit of Zyzyphus Jujube was tested for its possible anticancer effect and induction of apoptosis on human tumor cell lines, HEp-2, HeLa and Jurkat cell lines. The inhibitory effect of water extract of this fruit on cell proliferation was assessed by MTT colorimetric assay. The induction of apoptosis of this extract was analyzed by DNA fragmentation analysis. Zyzyphus Jujube extract showed inhibitory effects on mentioned cell lines. Jurkat leukemic line was found the most sensitive cells with IC50 of 0.1 μg mL−1. Our study also showed a typical DNA laddering in this cell line. The present study showed cytotoxic activity of Zyzyphus Jujube on tumor cells. Although Zyzyphus Jujube has useful compounds for medical applications.  相似文献   
108.
Genital Herpes is a common sexually transmitted disease that is caused mostly by Herpes simplex virus type 2 (HSV-2). Its prevalence has increased in developing countries in spite of the availability of valuable antiviral drug therapy. Considering the importance of HSV-2 infections, effective vaccines remain the most likely hope for controlling the spread of HSV diseases. In the present study, the complete HSV-2 glycoprotein D gene was isolated and cloned into different plasmid vectors to construct a DNA vaccine and prepare recombinant subunit vaccines using a baculovirus expression system. The vaccines were tested alone or in combination to evaluate their ability to induce protective immunity in guinea-pigs against genital HSV infections. Immunization elicited humoral responses as measured by neutralization tests and enzyme-linked immunosorbent assay, and immunized animals had less severe genital skin disease as well as reduced replication of the challenging virus in the genital tract during experimental infection. Our results further demonstrate that DNA priming-protein boosting induced a neutralizing antibody titer higher than that obtained with DNA-DNA vaccination. The massive increase of antibody titer following DNA priming-protein boosting might be attributed to a recall of B cell memory.  相似文献   
109.
In this study we are looking into two contradicting mutations found in prion protein (PrP) viz G127V and D178V, that are reportedly protective and pathogenic, respectively. Despite significant advances in comprehension of the role of pathogenic mutations, the role of protective mutation in amyloid fold inhibition still lacks a substantial basis. To understand the structural basis of protective mutation, molecular dynamics simulation coupled with protein-protein docking and molecular mechanics/Poisson-Boltzmann surface area analysis was used to understand the instant structural variability brought about by these mutations alone and in combination on PrP and prion-prion complex. Atomic-scale investigations successfully revealed that the binding pattern of prion-prion varies differentially in protective and pathogenic mutations with secondary structure showing distinct contrasting patterns, which could supposedly be a critical factor for differential prion behavior in protective and pathogenic mutations. Considering the reported role of an amyloid fold in prion-prion binding, the contrasting pattern has given us a lead in comprehending the role of these mutations and has been used in this study to look for small molecules that can inhibit amyloid fold for prion-prion interaction in pathogenic mutant carrying PrP.  相似文献   
110.
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