Oriented immobilization of enzymes helps to maintain their native structure and proper orientation for high-performance engineering to meet extensive biocatalysis demands.However,the supporting materials used for orie...Oriented immobilization of enzymes helps to maintain their native structure and proper orientation for high-performance engineering to meet extensive biocatalysis demands.However,the supporting materials used for orientated immobilization are usually costly or complicated in preparation,affecting their practical applications.In this work,a facile purification and immobilization method was proposed for enzyme immobilization based on organic-inorganic hybrid calcium phosphate nanocrystal(Ca Ps)induced by Cu^(2+) modified bovine serum albumin(BSA-Cu).Then,the as-prepared hybrid calcium phosphate nanosheet,BSA-Cu@Ca Ps,was utilized for one-pot purification and immobilization of His-tagged organophosphorus hydrolase(OPH)by metal-affinity binding to the incorporated BSA.BSA-Cu@Ca PsOPH exhibited enhanced p H stability and thermal stability compared to the free enzyme.Moreover,BSA-Cu@Ca Ps-OPH could retain more than 75%and 56%of initial activity after reuse 5 and 10 times,respectively.The results demonstrated that this facile strategy was promising for the effective biodegradation of organophosphorus pesticides with the immobilized enzyme.展开更多
The variation in the orbital period of the W UMa type contact binary V502 Oph is analyzed. The orbital period exhibits a wavelike variation with a periodicity of 23.0 years and an amplitude of AP = 1.24 ×10^-5 da...The variation in the orbital period of the W UMa type contact binary V502 Oph is analyzed. The orbital period exhibits a wavelike variation with a periodicity of 23.0 years and an amplitude of AP = 1.24 ×10^-5 days superimposed on secular decrease of dP/dt = 1.68× 10^-7 day per year. The long-term decrease may be accompanied by the contraction of the secondary at a rate of 83 m per year and a mass transfer rate from the primary to the secondary of 4.28×10^-8M· per year. The short-term oscillation may be explained by the presence of a third component. Orbital elements of the third body and its possible mass are presented.展开更多
We constructed an expression cassette of the organophosphorus pesticide degrading （opal） gene under the control of the E8 promoter. Then opd was transformed into tomato fruit using an agroinfiltration transient expr...We constructed an expression cassette of the organophosphorus pesticide degrading （opal） gene under the control of the E8 promoter. Then opd was transformed into tomato fruit using an agroinfiltration transient expression system. β-Glucuronidase （GUS） staining, reverse transcription-polymerase chain reaction （RT-PCR）, wavelength scanning, and fluorescent reaction were performed to examine the expression of the opd gene and the hydrolysis activity on coumaphos of organo- phosphorus hydrolase （OPH） in tomato fruit. The results show that the agroinfiltrated tomato fruit-expressed OPH had the maximum hydrolysis activity of about 11.59 Uhng total soluble protein. These results will allow us to focus on breeding transgenic plants that could not only enhance the degrading capability of fruit and but also hold no negative effects on pest control when spraying organophosphorus pesticides onto the seedlings in fields.展开更多
A bacterium with the capability of degrading organphosphorus, identified as Pseudomonas pseudoaicaligenes, is isolated from OP-treated soil. The organphosphorus hydrolase OPHC2 from this bacterium has been purified an...A bacterium with the capability of degrading organphosphorus, identified as Pseudomonas pseudoaicaligenes, is isolated from OP-treated soil. The organphosphorus hydrolase OPHC2 from this bacterium has been purified and characterized. OPHC2 has optimum activity for the reaction at 65℃ and pH 9.0 with methyl parathion as a substrate, it also shows good thermal and pH stability. Most metal ions and chemicals have no effect on the activity of OPHC2. The analyses of nucleotide sequence encoding OPHC2 and amino acid sequence of OPHC2 show that there are lower homologies with those of organphosphorus hydrolase reported in GenBank.展开更多
The corrosion behavior of copper in 3% NaCl solutions has been investigated using AES. XPS and photoelectrochemical tectniques. The results show that Cl- has remarkable influence on the corrosion behavior of copper. W...The corrosion behavior of copper in 3% NaCl solutions has been investigated using AES. XPS and photoelectrochemical tectniques. The results show that Cl- has remarkable influence on the corrosion behavior of copper. With the increasing immersion time, the photoresponse of copper electrode changes from p-type to n-type gradually, and the invasion degree of Cl- ions on copper electrode increases. Finally, the band gap of the sedriconduct film formed on copper electrode surface is 1 .7eV.展开更多
Twenty one cases of encephalomas were misdi-agnosed firstly in ophthalmology Departmant, which included 9 cases of pituitary adema, 7 cases of meningioma, 4 cases of craniophargngioma and 1 case of glioma. There were ...Twenty one cases of encephalomas were misdi-agnosed firstly in ophthalmology Departmant, which included 9 cases of pituitary adema, 7 cases of meningioma, 4 cases of craniophargngioma and 1 case of glioma. There were 19 cases whose lesions located in sella turrica region and 2 cases in occipital lobe. The first ophtha1mic symptom was mostly the diminishing of visual acuity, usually accompanied by systemic dis-comfort such as headache and disturbance of endocrine system. These encephalomas were falsely diagnosed as retrobulbar neuritis, retinitis, optic atrophy and ametropia and so on. The reasons of misdiagnosis were analyzed and discussed.展开更多
基金supported by the National Key Research and Development Program of China(2021YFC2102801)the National Natural Science Foundation of China(21621004)。
文摘Oriented immobilization of enzymes helps to maintain their native structure and proper orientation for high-performance engineering to meet extensive biocatalysis demands.However,the supporting materials used for orientated immobilization are usually costly or complicated in preparation,affecting their practical applications.In this work,a facile purification and immobilization method was proposed for enzyme immobilization based on organic-inorganic hybrid calcium phosphate nanocrystal(Ca Ps)induced by Cu^(2+) modified bovine serum albumin(BSA-Cu).Then,the as-prepared hybrid calcium phosphate nanosheet,BSA-Cu@Ca Ps,was utilized for one-pot purification and immobilization of His-tagged organophosphorus hydrolase(OPH)by metal-affinity binding to the incorporated BSA.BSA-Cu@Ca PsOPH exhibited enhanced p H stability and thermal stability compared to the free enzyme.Moreover,BSA-Cu@Ca Ps-OPH could retain more than 75%and 56%of initial activity after reuse 5 and 10 times,respectively.The results demonstrated that this facile strategy was promising for the effective biodegradation of organophosphorus pesticides with the immobilized enzyme.
基金Supported by the National Key Fundamental Research Project.
文摘The variation in the orbital period of the W UMa type contact binary V502 Oph is analyzed. The orbital period exhibits a wavelike variation with a periodicity of 23.0 years and an amplitude of AP = 1.24 ×10^-5 days superimposed on secular decrease of dP/dt = 1.68× 10^-7 day per year. The long-term decrease may be accompanied by the contraction of the secondary at a rate of 83 m per year and a mass transfer rate from the primary to the secondary of 4.28×10^-8M· per year. The short-term oscillation may be explained by the presence of a third component. Orbital elements of the third body and its possible mass are presented.
基金Project supported by the National Key Technology R&D Program of China(No.2007BAD59B06)the International Science and Technology Cooperation Program of China(No.2007DFA31260)
文摘We constructed an expression cassette of the organophosphorus pesticide degrading （opal） gene under the control of the E8 promoter. Then opd was transformed into tomato fruit using an agroinfiltration transient expression system. β-Glucuronidase （GUS） staining, reverse transcription-polymerase chain reaction （RT-PCR）, wavelength scanning, and fluorescent reaction were performed to examine the expression of the opd gene and the hydrolysis activity on coumaphos of organo- phosphorus hydrolase （OPH） in tomato fruit. The results show that the agroinfiltrated tomato fruit-expressed OPH had the maximum hydrolysis activity of about 11.59 Uhng total soluble protein. These results will allow us to focus on breeding transgenic plants that could not only enhance the degrading capability of fruit and but also hold no negative effects on pest control when spraying organophosphorus pesticides onto the seedlings in fields.
文摘A bacterium with the capability of degrading organphosphorus, identified as Pseudomonas pseudoaicaligenes, is isolated from OP-treated soil. The organphosphorus hydrolase OPHC2 from this bacterium has been purified and characterized. OPHC2 has optimum activity for the reaction at 65℃ and pH 9.0 with methyl parathion as a substrate, it also shows good thermal and pH stability. Most metal ions and chemicals have no effect on the activity of OPHC2. The analyses of nucleotide sequence encoding OPHC2 and amino acid sequence of OPHC2 show that there are lower homologies with those of organphosphorus hydrolase reported in GenBank.
文摘The corrosion behavior of copper in 3% NaCl solutions has been investigated using AES. XPS and photoelectrochemical tectniques. The results show that Cl- has remarkable influence on the corrosion behavior of copper. With the increasing immersion time, the photoresponse of copper electrode changes from p-type to n-type gradually, and the invasion degree of Cl- ions on copper electrode increases. Finally, the band gap of the sedriconduct film formed on copper electrode surface is 1 .7eV.
文摘Twenty one cases of encephalomas were misdi-agnosed firstly in ophthalmology Departmant, which included 9 cases of pituitary adema, 7 cases of meningioma, 4 cases of craniophargngioma and 1 case of glioma. There were 19 cases whose lesions located in sella turrica region and 2 cases in occipital lobe. The first ophtha1mic symptom was mostly the diminishing of visual acuity, usually accompanied by systemic dis-comfort such as headache and disturbance of endocrine system. These encephalomas were falsely diagnosed as retrobulbar neuritis, retinitis, optic atrophy and ametropia and so on. The reasons of misdiagnosis were analyzed and discussed.
