Nuclei from isolated nerve cells were sampled by microdissection. The content and composition of the nuclear RNA was studied and compared with that of the cytoplasmic RNA of Deiters' nerve cells of rabbits. Analyses were made of control nerve cells and of cells in which an enhanced RNA and protein production had been induced by chemical means, tricyano-amino-propene, for 60 minutes. The nuclear...

An insertion mutant of herpes simplex virus type 1 has been constructed which carries the lacZ gene from Escherichia coli within the coding sequence of gene UL2, which is in the long unique region of the genome. In a one-step growth curve experiment this recombinant (called in 1601) grew as well as the wild-type (wt) parent virus, indicating that the UL2 gene is dispensable for growth in tissue...

Archaeal family-D DNA polymerases (Pol-D) comprise a small (DP1) proofreading subunit and a large (DP2) polymerase subunit. Pol-D is one of the least studied polymerase families, and this publication investigates the enzyme from Archaeoglobus fulgidus (Afu Pol-D). The C-terminal region of DP2 contains two conserved cysteine clusters, and their roles are investigated using site-directed mutagene...

The objectives of the investigation of the nutrition of Clostridiu,m perfringens were twofold. In the first place, the development of a chemically defined medium was prerequisite for the understanding of the factors and conditions favorable to production of t#oxins or exoenzymes. Secondly, it became evident early in the investigation that the organism presented exceptional advantages as a means...

Neither intact nor regenerating planaria incorporated any signiiicant amount of tritiated thymidine, tritiated L-leucine, or C14-Lleucine from free solution even over long periods of exposure. Tritiated thymidine was incorporated into regenerating rat liver and fed to planaria, but tritium hydrogen exchange rendered this method useless. A large incorporation of C14-uracil and C14-Lleucine into ...

Various octadeoxynucleotides containing uracil at different positions were synthesized and submitted to the action of Escherichia coli and Micrococcus luteus uracil-DNA glycosylases. A uracil residue situated at the 5'-end was excised by the M.luteus enzyme but not by the E.coli one. Uracil residues located at the ultimate and penultimate positions at the 3'-end were not cleaved by either enzym...

Uracil DNA glycosylases (UDGs) excise uracil fromDNA and initiate the base (uracil) excision repair pathway. Ung, a highly conserved protein, is the only UDG characterized so far in mycobacteria. Here, we show that Rv1259 fromMycobacterium tuberculosis codes for a doublestranded DNA (dsDNA) specific UDG (MtuUdgB). MtuUdgB is thermo-tolerant, contains Fe–S cluster and, in addition to uracil, it ...

Purified recombinant human dihydropyrimidine dehydrogenase (hDPD) was incubated with (14)C-labeled (E)-5-(2-bromovinyl)uracil ([(14)C]BVU) in the presence of NADPH to investigate a possible mechanism in the 18 patient deaths caused by interactions of 5-fluorouracil prodrugs with the new oral antiviral drug, sorivudine. BVU is formed from sorivudine by gut flora and absorbed through intestinal m...

Bacteriophage T5 induces a deoxyuridine 5'-triphosphate nucleotidohydrolase (dUTPase) activity during infection of Escherichia coli. A T5 mutant (T5 dut) unable to induce this dUTPase activity has been isolated. Although this mutant is viable, the E. coli dUTPase activity is not sufficiently active to exclude uracil from the progeny DNA and about 3% of the thymine is replaced by uracil. When th...

Uracil is incorporated into newly synthesized DNA by mutants of Escherichia coli with reduced levels of dUTPase (dUTP nucleotidohydrolase; EC 3.6.1.23). Excision-repair of the incorporated uracil results in the generation of labeled DNA fragments that appear after brief pulses with [(3)H]thymidine [Tye, B-K., Nyman, P.-D., Lehman, I. R., Hochhauser, S. & Weiss, B. (1977) Proc. Natl. Acad. Sci. ...