The objective of this research was to isolate a dichlorvos (2,2-dichlorovinyl dimethyl phosphate)-degrading strain of Ochrobactrum sp., and determine its effectiveness in remediation of a dichlorvos-contaminated soil....The objective of this research was to isolate a dichlorvos (2,2-dichlorovinyl dimethyl phosphate)-degrading strain of Ochrobactrum sp., and determine its effectiveness in remediation of a dichlorvos-contaminated soil. A dichlorvos-degrading bacterium (strain DDV-1) was successfully isolated and identified as an Ochrobactrumsp. based on its 16S rDNA sequence analysis. Strain DDV-1 was able to utilize dichlorvos as a sole carbon source, and the optimal pH and temperature for its cell growth and degradation were 7.0 and 30 ℃, respectively. Also, the growth and degradation of strain DDV-1 showed the same response to dissolved oxygen. In addition, the soil degradation test indicated that in soil spiked with 100 mg L-1 or 500 mg L-1 dichlorvos and inoculated with 0.5% or 1.0% (v/v) strain DDV-1, complete degradation of dichlorvos could be achieved in 24 h. The present study showed that strain DDV-1 was a fast dichlorvos-degrading bacterium in soil. However, further research will be needed to clarify the degradation pathway and the properties of the key enzymes involved in its biodegradation.展开更多
Human adenoviruses(HAdvs)are major respiratory pathogens.Specifically,human adenovirus type 4(HAdV4)and human adenovirus type 7(HAdV7)are known for causing fever and pneumonia,with docu-mented cases of fatalities amon...Human adenoviruses(HAdvs)are major respiratory pathogens.Specifically,human adenovirus type 4(HAdV4)and human adenovirus type 7(HAdV7)are known for causing fever and pneumonia,with docu-mented cases of fatalities among the population.In recent years,HAdV4/HAdv7 has been implicated in caus-ing substantial outbreaks,leading to increased morbidity in multiple countries.Most HAdV4 and HAdV7 infections have been reported in North America,Asia,Europe,Africa,South America,Oceania,and the Middle East.Most fatalities occurred in North America(the United States)and Asia(China and Singapore).Engineered recombinant adenoviruses have played a crucial role as vaccine vectors.In this study,we con-structed a recombinant adenovirus,Ad4ITRmut-Ad7E3,and evaluated it in vitro and in vivo.We observed that the replication rate of Ad4ITRmut-Ad7E3 was lower than that of the RI-67 strain,indicating that the mutation of inverted terminal repeats(ITRs)weakened the replication ability of HAdV4.Immunization of BALB/c mice with the bivalent Ad4ITRmut-Ad7E3 vaccine strain,administered by intraperitoneal injection and oral gavage,resulted in the elicitation of neutralizing antibodies targeting HAdV4 and HAdv7.This finding not only pro-vides a novel method and technique for the efficient construction of a polyvalent recombinant adenovirus vac-cine candidate against HAdV4 and HAdv7 but also against other prevalent adenovirus serotypes such as HAdV3,HAdV11,HAdV14,and HAdv55,from various regions.展开更多
基金Project supported by the National High Technology Research and Development Program of China (863 Program)(Nos.2001AA214121, 2002AA246081 and 2003AA241150)the National Key Technologies Research and Development Program of China during the 9th Five-Year Plan Period (No. 2002BA516A01)the National Natural Science Foundation of China (No. 30400013).
文摘The objective of this research was to isolate a dichlorvos (2,2-dichlorovinyl dimethyl phosphate)-degrading strain of Ochrobactrum sp., and determine its effectiveness in remediation of a dichlorvos-contaminated soil. A dichlorvos-degrading bacterium (strain DDV-1) was successfully isolated and identified as an Ochrobactrumsp. based on its 16S rDNA sequence analysis. Strain DDV-1 was able to utilize dichlorvos as a sole carbon source, and the optimal pH and temperature for its cell growth and degradation were 7.0 and 30 ℃, respectively. Also, the growth and degradation of strain DDV-1 showed the same response to dissolved oxygen. In addition, the soil degradation test indicated that in soil spiked with 100 mg L-1 or 500 mg L-1 dichlorvos and inoculated with 0.5% or 1.0% (v/v) strain DDV-1, complete degradation of dichlorvos could be achieved in 24 h. The present study showed that strain DDV-1 was a fast dichlorvos-degrading bacterium in soil. However, further research will be needed to clarify the degradation pathway and the properties of the key enzymes involved in its biodegradation.
基金supported by grants from the National Key Research and Development Program of China(Grant No.2018YFA0900800).
文摘Human adenoviruses(HAdvs)are major respiratory pathogens.Specifically,human adenovirus type 4(HAdV4)and human adenovirus type 7(HAdV7)are known for causing fever and pneumonia,with docu-mented cases of fatalities among the population.In recent years,HAdV4/HAdv7 has been implicated in caus-ing substantial outbreaks,leading to increased morbidity in multiple countries.Most HAdV4 and HAdV7 infections have been reported in North America,Asia,Europe,Africa,South America,Oceania,and the Middle East.Most fatalities occurred in North America(the United States)and Asia(China and Singapore).Engineered recombinant adenoviruses have played a crucial role as vaccine vectors.In this study,we con-structed a recombinant adenovirus,Ad4ITRmut-Ad7E3,and evaluated it in vitro and in vivo.We observed that the replication rate of Ad4ITRmut-Ad7E3 was lower than that of the RI-67 strain,indicating that the mutation of inverted terminal repeats(ITRs)weakened the replication ability of HAdV4.Immunization of BALB/c mice with the bivalent Ad4ITRmut-Ad7E3 vaccine strain,administered by intraperitoneal injection and oral gavage,resulted in the elicitation of neutralizing antibodies targeting HAdV4 and HAdv7.This finding not only pro-vides a novel method and technique for the efficient construction of a polyvalent recombinant adenovirus vac-cine candidate against HAdV4 and HAdv7 but also against other prevalent adenovirus serotypes such as HAdV3,HAdV11,HAdV14,and HAdv55,from various regions.