After Escherichia coli HB101 with plasmid pWH58, pWH98, or pTBa 5 were cultered respectively in amp LB broth which contained 50 mg/L CdCl 2 constantly for 24h, these plasmids were isolated from E. coli, and the ...After Escherichia coli HB101 with plasmid pWH58, pWH98, or pTBa 5 were cultered respectively in amp LB broth which contained 50 mg/L CdCl 2 constantly for 24h, these plasmids were isolated from E. coli, and the effect of excessive CdCl 2 on the E. coli HB101 and plasmid DNA was studied by surveying the growth of E. coli HB101 and plasmid, argarose gel electrophoresis and analysis of restriction fragment length polymorphism (RFLP) of plasmids, and plasmid transformation. The results showed that 50 mg/L CdCl 2 treatment lagged the growth of E. coli HB101 for at least 4h, but after grown for 24h there were not significant differences in the growths of E. coli HB101s and the productions of plasmids between the treatment and control. These results implified that E. coli HB101 have induced adaptability to cadmium stress and excessive CdCl 2 did not inhibit the replication and amp + genes expression of plasmid DNA in vivo of E. coli significantly. 50 mg/L CdCl 2 treatment for 24 hours might cause the sequences change of plasmid DNA, but could not lead to the random breakage of plasmid DNA strands. Moreover, after 50 mg/L of CdCl 2 treatment in vivo the transformation activities of plasmid did not altered, implied excessive CdCl 2 could not affect the superhelical structure of plasmid and also not break the loop of plasmid DNA evidently.展开更多
Curcurbit[n]uril(Q[n])-based supramolecular frameworks(QSFs) constructed from the outer surface interaction of Q[n]s(OSIQ) have the characteristic of simplicity,diversity and modulability.Their simplicity is reflected...Curcurbit[n]uril(Q[n])-based supramolecular frameworks(QSFs) constructed from the outer surface interaction of Q[n]s(OSIQ) have the characteristic of simplicity,diversity and modulability.Their simplicity is reflected in their simple composition and preparation methods used for QSFs.The diversity of supramolecular organic frameworks(SOFs) is reflected in the synthesis methods and structural characteristics of the as-obtained QSFs,as well as the variety of structural directing agents and basic building blocks used to prepare QSFs.The modulability is reflected by the controllable channel size in the QSFs,which can be adjusted using different sizes of Q[n]s.In this work,the first re ported cucurbituril Q[6]was selected as the basic building block and three Q[6]-based su p ramolecular frameworks were obtained from aqueous HCl solutions in the presence of [CdCl_(4)]^(2-)respectively.The OSIQs are the main driving forces for the formation of these frameworks.This study shows the diversity of the QSFs.展开更多
文摘After Escherichia coli HB101 with plasmid pWH58, pWH98, or pTBa 5 were cultered respectively in amp LB broth which contained 50 mg/L CdCl 2 constantly for 24h, these plasmids were isolated from E. coli, and the effect of excessive CdCl 2 on the E. coli HB101 and plasmid DNA was studied by surveying the growth of E. coli HB101 and plasmid, argarose gel electrophoresis and analysis of restriction fragment length polymorphism (RFLP) of plasmids, and plasmid transformation. The results showed that 50 mg/L CdCl 2 treatment lagged the growth of E. coli HB101 for at least 4h, but after grown for 24h there were not significant differences in the growths of E. coli HB101s and the productions of plasmids between the treatment and control. These results implified that E. coli HB101 have induced adaptability to cadmium stress and excessive CdCl 2 did not inhibit the replication and amp + genes expression of plasmid DNA in vivo of E. coli significantly. 50 mg/L CdCl 2 treatment for 24 hours might cause the sequences change of plasmid DNA, but could not lead to the random breakage of plasmid DNA strands. Moreover, after 50 mg/L of CdCl 2 treatment in vivo the transformation activities of plasmid did not altered, implied excessive CdCl 2 could not affect the superhelical structure of plasmid and also not break the loop of plasmid DNA evidently.
基金the financial support of the National Natural Science Foundation of China(Nos.21761007,51663005 and 21871064)Science and Technology Plan Project of Guizhou Province(Nos.20175788 and 20185781)。
文摘Curcurbit[n]uril(Q[n])-based supramolecular frameworks(QSFs) constructed from the outer surface interaction of Q[n]s(OSIQ) have the characteristic of simplicity,diversity and modulability.Their simplicity is reflected in their simple composition and preparation methods used for QSFs.The diversity of supramolecular organic frameworks(SOFs) is reflected in the synthesis methods and structural characteristics of the as-obtained QSFs,as well as the variety of structural directing agents and basic building blocks used to prepare QSFs.The modulability is reflected by the controllable channel size in the QSFs,which can be adjusted using different sizes of Q[n]s.In this work,the first re ported cucurbituril Q[6]was selected as the basic building block and three Q[6]-based su p ramolecular frameworks were obtained from aqueous HCl solutions in the presence of [CdCl_(4)]^(2-)respectively.The OSIQs are the main driving forces for the formation of these frameworks.This study shows the diversity of the QSFs.