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S Sarid

Publications and source records attributed to S Sarid.

29 records · Page 2Linked to original sources
PubMed1970

In vitro transcription of a transfer RNA gene.

The Escherichia coli tRNA(Tyr) gene carried by the varphi80psu(3) + transducing phage was transcribed in vitro by DNA-dependent RNA polymerase. The enzymatically synthesized tRNA(Tyr)-like polynucleotide chains were detected by competition with purified E. coli(32)P-tRNA(Tyr) for specific hybridization sites on varphi80psu(3) + DNA. Analysis by sucrose gradient centrifugation showed the tRNA(Tyr)-like chains to possess a heterogeneous distribution with respect to sedimentation coefficients, with a broad peak around 8 S. The presence of the termination factor rho during the transcription did not significantly reduce the average size of the in vitro synthesized tRNA(Tyr)-like chains.

Bacteriophages↗
PubMed1967

Differential effect of polyamines on T4 morphogenesis.

The 5-fluorouracil (5 FU) technique for the phenotypic reversion of amber mutants was used to demonstrate that under certain circumstances, in the presence of putrescine or spermidine, early mutants have an enhanced response to 5 FU, whereas late mutants have a delayed response. Bacteria infected by T4D wild-type bacteriophage did not produce phage in the presence of high putrescine concentrations. Pulse treatments with putrescine showed that the production of lysozyme depends on a putrescine-sensitive process that begins immediately after infection at 26 C and ends at 36 min or even later. The addition of putrescine at any time during the critical period between 0 and 36 min led to a corresponding delay in lysozyme synthesis after the inhibitor was removed. Intracellular phage maturation was delayed by the addition of 100 mumoles of putrescine per ml. Early enzymes were not affected by the diamine, but the level of phage deoxyribonucleic acid was considerably decreased by the inhibitor. The putrescine-sensitive process that affects the timing of maturation is suggested to be the natural process controlling the T4 "clock."

Amines↗