Here we describe a solution to a common problem encountered in recombinant DNA cloning when directional cloning of a DNA fragment into a predetermined plasmid requires the use of restriction enzymes with adjacent or overlapping recognition sites. In preparing the double-digested plasmid, only one enzyme will often cut, whereas the second will not because of the lack of a sufficiently long stret...

A gene (gshI) responsible for gamma-glutamylcysteine synthetase (GSH-I) activity was cloned to construct an Escherichia coli B strain having high glutathione synthesizing activity. For this purpose, two E. coli B mutants (strains C912 and RC912) were used. C912 was deficient in GSH-I activity. RC912, a revertant of C912, had a GSH-I activity that was desensitized to feedback inhibition of reduc...

objective(s): fascioliasis is a zoonotic parasitic disease caused by liver fluke species of fasciola hepatica and fasciola gigantica. differentiation of these two species, based on their morphological characteristics, is difficult. the current study aimed to use pcr-rflp assay to distinguish between f. hepatica and f. gigantica , based on profiles of rflp, produced by effect of endonucleases on...

The HpaI E fragment (0-4.5 map units) of adenovirus type 2 (Ad2) DNA was cloned in the plasmid vector pBR322. Excision of the viral insert with PstI and XbaI generated a fragment which comigrated with Ad2 XbaI-E (0-3.8 map units), and this fragment was ligated to the 3.8-100 fragment generated by XbaI cleavage of the DNA of the Ad5 mutant, dl309 (N. Jones and T. Shenk, Cell 17:683-689, 1979). T...

Sweet lime split bark is a disorder of increasing importance in Fars province. Previously we showed that a new variant of hop stunt viroid (HSVd-sb) was related to the disorder. It had homology with a noncachexia variant of hop stunt viroid (CVd-IIa-117) which causes cracking the bark of trifoliate orange rootstocks. In this study, showed that M.NgoBIX, BglI and BsrI restriction enzymes can c...