A novel type of aeetohydrexyacid synthase inhibitors, 4-methyl-3-isoxazolidinone derivatives of sulfonylurea, was designed and synthesized. The structures of these compounds were confirmed by using MS, NMR, and elemen...A novel type of aeetohydrexyacid synthase inhibitors, 4-methyl-3-isoxazolidinone derivatives of sulfonylurea, was designed and synthesized. The structures of these compounds were confirmed by using MS, NMR, and elemental analysis. The results of preliminary active tests indicate that the compounds show a herbicidal activity.展开更多
To overcome ampicillin-resistance of bacteria which is believed to attribute their endogenous B-lactamase, we designed three 10-23 DNAzymes（Dz1, Dz2. Dz3） targeting the coding region of B-lactamase mRNA and examined...To overcome ampicillin-resistance of bacteria which is believed to attribute their endogenous B-lactamase, we designed three 10-23 DNAzymes（Dz1, Dz2. Dz3） targeting the coding region of B-lactamase mRNA and examined their inhibitory capabilities of the ampicillin-resistance of TEM-1 and TEM-3 bacteria. Dz1 was a traditional 10-23 DNAzyme, Dz2 was the mutant of Dz1 by addition of the protected nucleotide to each ann of the enzyme, and Dz3 was a mutant of Dz1 at antisense arms of which phosphorothioate modifications were made. Kinetic analysis, bacterial growth, and β-lactamase activity measurement showed that all the three DNAzymes worked efficiently in vitro and in vivo. A 9 hours bacterial growth inhibition test showed that the inhibition rates of TEM-1 bacteria by Dz1, Dz2, and Dz3 were 27%, 50%, and 29%, respectively. In addition, the inhibition rates of TEM-3 bacteria by those three DNAzymes were found io be 49%, 58%, and 45%, respectively. The current findings suggest that DNAzymes may become potential candidates of alternative inhibitors for bacteria drug-resistance.展开更多
Cu,Zn SOD is a highly conserved enzyme and the controversy about its evolutionary possibility in the near future has been lively. In order to further our understanding of the future fate of human Cu,Zn SOD, we adopt...Cu,Zn SOD is a highly conserved enzyme and the controversy about its evolutionary possibility in the near future has been lively. In order to further our understanding of the future fate of human Cu,Zn SOD, we adopted a strategy relating to the directed evolution to study how the mutants of human Cu,Zn SOD respond to different oxidative stress. After five rounds of screening, we found a mutant that can survive under harsh pressures and DNA sequencing proves that it shows a mutation responsible for the phenomenon. However, under natural pressure, our screening comes to nothing. Then we may draw the following conclusions: the evolution of biological macromolecules in some respect depends on their surroundings and if they are too familiar with a certain environment, they may embody evolutionary inertia.展开更多
Affinity-mediated protein separation is an integral part of proteomics, the most outstanding of which is immunoproteomics. However, in the immunoprecipitate system overwhelming Ab and Ag conceal Ag interacting protein...Affinity-mediated protein separation is an integral part of proteomics, the most outstanding of which is immunoproteomics. However, in the immunoprecipitate system overwhelming Ab and Ag conceal Ag interacting proteins as the research targets, which is the rate-limiting step in the progress of comparative proteomic analyses. We presented a convenient and accurate method to tackle this problem. 1 mol/L NaCl elution buffer was applied to the complex Rubisco immunoprecipitate of Arabidopsis, the weakest force involved in the system was selectively broken up, resulting in the enrichment of Rubisco interacting proteins accessible for further comparative protein gel profile. The easy-to-use method sheds light on a narrow-down strategy supplement for comparative immunoproteomics.展开更多
文摘A novel type of aeetohydrexyacid synthase inhibitors, 4-methyl-3-isoxazolidinone derivatives of sulfonylurea, was designed and synthesized. The structures of these compounds were confirmed by using MS, NMR, and elemental analysis. The results of preliminary active tests indicate that the compounds show a herbicidal activity.
基金the National Natural Science Foundation of China(Nos.20771030 and 20671025)
文摘To overcome ampicillin-resistance of bacteria which is believed to attribute their endogenous B-lactamase, we designed three 10-23 DNAzymes（Dz1, Dz2. Dz3） targeting the coding region of B-lactamase mRNA and examined their inhibitory capabilities of the ampicillin-resistance of TEM-1 and TEM-3 bacteria. Dz1 was a traditional 10-23 DNAzyme, Dz2 was the mutant of Dz1 by addition of the protected nucleotide to each ann of the enzyme, and Dz3 was a mutant of Dz1 at antisense arms of which phosphorothioate modifications were made. Kinetic analysis, bacterial growth, and β-lactamase activity measurement showed that all the three DNAzymes worked efficiently in vitro and in vivo. A 9 hours bacterial growth inhibition test showed that the inhibition rates of TEM-1 bacteria by Dz1, Dz2, and Dz3 were 27%, 50%, and 29%, respectively. In addition, the inhibition rates of TEM-3 bacteria by those three DNAzymes were found io be 49%, 58%, and 45%, respectively. The current findings suggest that DNAzymes may become potential candidates of alternative inhibitors for bacteria drug-resistance.
文摘Cu,Zn SOD is a highly conserved enzyme and the controversy about its evolutionary possibility in the near future has been lively. In order to further our understanding of the future fate of human Cu,Zn SOD, we adopted a strategy relating to the directed evolution to study how the mutants of human Cu,Zn SOD respond to different oxidative stress. After five rounds of screening, we found a mutant that can survive under harsh pressures and DNA sequencing proves that it shows a mutation responsible for the phenomenon. However, under natural pressure, our screening comes to nothing. Then we may draw the following conclusions: the evolution of biological macromolecules in some respect depends on their surroundings and if they are too familiar with a certain environment, they may embody evolutionary inertia.
基金Supported by the National Natural Science Foundation of China(Nos.30470159 and C01020304)
文摘Affinity-mediated protein separation is an integral part of proteomics, the most outstanding of which is immunoproteomics. However, in the immunoprecipitate system overwhelming Ab and Ag conceal Ag interacting proteins as the research targets, which is the rate-limiting step in the progress of comparative proteomic analyses. We presented a convenient and accurate method to tackle this problem. 1 mol/L NaCl elution buffer was applied to the complex Rubisco immunoprecipitate of Arabidopsis, the weakest force involved in the system was selectively broken up, resulting in the enrichment of Rubisco interacting proteins accessible for further comparative protein gel profile. The easy-to-use method sheds light on a narrow-down strategy supplement for comparative immunoproteomics.
