The recombinant plas-mid pHC20 carrying bacteriophage T4 gene 42 and imm was extracted from clone CC20 and transformed into E. coli CSR603 (recA-,uvrA-,phr-1-).
woodson was established by subculturing for more than two years. We obtained the following results from our experiments. (1)MS+6BA 1mg/L+NAA 2mg/L for callus induction, MS+6BAlmg/
Five so- maclones HC-2,HC-3,HC-4,HC-5 and HC-0 have been selected; their plantlet regeneration frequency remained high through long-tern subculture,being more than 90% by 892 days.
BamHI C fragment of Herpes Simples Virus type 1 (HSV-1) DNA has been subcloned by recombinant DNA technique and the cloning system of 8 small fragments of the BamHI C fragment was established.
Results of clone formation and Flow cytometry analysis (FCAS) suggested that prodigiosin has the capability of restraining mitosis by regulating the cell cycle.
The results showed that, feeding on clone 7, the activity of esterase, carboxylesterase, and mixed-function oxidases in the midgut of the larvae was very much decreased.
However, the activities of glutathione S-transferase and proteinase were complex, increased markedly after 24 h feeding on clone 7, and then declined rapidly.
Parmi les protéines sécrétées identifiées figurent un nouvel homologue PCN de la chorismate mutase ainsi qu'un ADNc récemment cloné à partir de cellules glandulaires de Meloidogyne javanica.
Inactivation experiments had shown that two putative acyl carrier proteins, CloN5 and CloN1, and two putative acyl transferases, CloN2 and CloN7, are involved in the transfer of the pyrrolyl-2-carboxyl moiety to the deoxysugar.
In this study, pyrrolyl-2-carboxyl-N-acetylcysteamine thioester was synthesized and fed to cloN1-, cloN2- and cloN7- mutants, and secondary metabolite formation was analyzed by HPLC and HPLC-MS.
Transfer of the pyrrolyl-2-carboxyl moiety was observed in the cloN1- and cloN2- mutants, but not in the cloN7- mutant, suggesting that CloN7 is responsible for this reaction.
Hind III cleavage products off DNA were ligated to a vector plasmid pBR322. Reeombinants AprTc8 were screened by insertion inactivation and were enriched by DL-cycloserine. Of 648 Apr transformants examined, 120 contain insertion of λ-Hind Ⅲ fragments. Clone containing recombinant plasmid pAG-5 was chosen for further study. Evidence for presence of A DNA in pAG-5 plasmid was obtained by isolating the recombinant plasmid DNA from it, and analyzing this DNA on agarose gels. Reeom-binant plasmid pAG-5 has a sl...
The callus was derived from the stem segments bearing buds (5-year-old) of Panax ginseng C. A. Meyer in 1975. The growth of the callus was the best on 67-V medium. The optimum temperature and pH for callus growth were 23±1℃ and about 6 respectively under our experimental conditions. Light apparently inhibited the growth of callus.The growth curve of ginseng callus for the cultural period was Sigmoid. Maximum growth of cultured callus was obtained during the period from the 4 th to the 6 th weeks after inocu...