scholarly journals Study on the Degradation Effect of Three Organophosphorus Hydrolase Mutant on Sarin

2021 ◽  
Vol 271 ◽  
pp. 03054
Author(s):  
Qiamin Gu ◽  
Chuanxin Zhao ◽  
Hailing Xi ◽  
Min Liu ◽  
Gaoyun Chen

Organophosphorus hydrolase can effectively degrade organic phosphorus compounds such as sarin. In this study, we constructed a recombinant Bacillus subtilis mutant expressing organophosphorus hydrolase, measured the effect of the mutant on the degradation rate of nerve agent sarin, and selected the optimal mutation scheme. Three different hydrolase mutant genes, 257L, 257Y and 303T, were ligated to PMA0911 vector and transferred into Bacillus subtilis WB800 to construct the target recombinant strain successfully. The recombinant bacteria secreted the target protein by fermentation. The effect of enzyme protein on the degradation of sarin was determined by the benzidine method. The optimal mutant was screened, and its enzymatic performance was explored. The effects of three organophosphorus hydrolase mutants on the hydrolysis rate of sarin were detected. The results showed that the 257Y mutant accelerated the hydrolysis of sarin significantly. Point mutation can improve the enzyme activity of wild-type organophosphorus hydrolase to a certain extent, laying the foundation for subsequent in-depth research.

1977 ◽  
Vol 22 (3) ◽  
pp. 415-422 ◽  
Author(s):  
M. G. Rodel ◽  
D. E. Armstrong ◽  
R. F. Harris

2015 ◽  
Vol 03 (02) ◽  
pp. 39-51 ◽  
Author(s):  
Irenus A. Tazisong ◽  
Zachary N. Senwo ◽  
Zhongqi He

Author(s):  
H. W. Harvey

A simple photoelectric meter is described which allows the molybdenum blue formed in sea water, due to the presence of phosphate, to be estimated within that due to ± 0·25 mg. phosphate-P per m.3.The effects of concentration of acid, molybdate, reductant, temperature and suspended particles on the rate of formation, fading and amount of molybdenum blue, formed in sea waters containing phosphate are detailed.Intramolecular changes taking place during storage of molybdate solutions, and while being mixed with acidified sea water, have been investigated.The hydrolysis of organic phosphorus compounds in acidified sea water at 140° C , and the prevention of arsenate formation, are described.Procedures, resulting from these investigations, for the estimation of phosphate, and of total phosphorus, are described.The growth of bacteria and the physical adsorption of organic phosphorus compounds in solution on the walls of glass vessels used for storage of sea water have been investigated, and a method of prevention evolved.


1953 ◽  
Vol 31 (10) ◽  
pp. 976-983 ◽  
Author(s):  
R. A. B. Bannard ◽  
J. R. Gilpin ◽  
G. R. Vavasour ◽  
A. F. McKay

Hydroxymethanephosphonic acid was prepared by treating paraformaldehyde with phosphorus trichloride at atmospheric pressure and subsequent hydrolysis of the resultant complex. Chloromethanephosphonyl dichloride was obtained by chlorination of hydroxymethanephosphonic acid with thionyl.chloride in the presence of pyridine. On the other hand hydroxymethanephosphonic acid combined slowly with phosphorus pentachloride to give the hitherto unknown dichlorophosphorylmethanephosphonyl dichloride, Cl2P(O)OCH2P(O)Cl2, together with chloromethanephosphonyl dichloride. The structure of dichlorophosphorylmethanephosphonyl dichloride was confirmed by its conversion with phosphorus pentachloride at 78 °C into chloromethanephosphonyl dichloride and phosphorus oxychloride. The preparation of chloromethanephosphonyl dichloride by interaction of paraformaldehyde and phosphorus trichloride in an autoclave at 250 °C was studied in reference to the influence of heating time on the yield.


2021 ◽  
Vol 9 (9) ◽  
pp. 1961
Author(s):  
Kaixuan Huang ◽  
Yanqing Zhuang ◽  
Zhou Wang ◽  
Linjian Ou ◽  
Jingyi Cen ◽  
...  

Karenia mikimotoi is one of the most well-known harmful bloom species in temperate coastal waters. The present study investigated the characteristics of alkaline phosphatase (APase) and phosphodiesterase (PDEase) activities in hydrolysis of two phosphomonoesters (adenosine triphosphate (ATP) and ribulose 5-phosphate (R5P)) and a phosphodiester (cyclic adenosine monophosphate (cAMP)) in K. mikimotoi and compared its growth and physiological responses to the different forms of phosphorus substrates. K. mikimotoi produced comparable quantities of APase and PDEase to hydrolyze the organic phosphorus substrates, although hydrolysis of the phosphomonoesters was much faster than that of the phosphodiester. The growth of K. mikimotoi on organic phosphorus substrates was comparable to or better than that on inorganic phosphate. The difference in particulate organic nutrients (carbon, nitrogen, and phosphorus) and hemolytic activity supported different rates of hydrolysis-assimilation of the various organic phosphorus substrates by K. mikimotoi. The hemolytic activities of K. mikimotoi in the presence of organic phosphorus substrates were several times those in the presence of inorganic phosphate during the exponential phase. This suggested the potential important role of organic phosphorus in K. mikimotoi blooms.


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