Cyanocycline A was cytotoxic against Meth A cells in vitro, and also showed marked activity against the same cell line grown as an experimental ascites tumor. This antibiotic inhibited nucleic acid synthesis in Escherichia coli and Meth A cells. The antimicrobial activity of the antibiotic was reversed by addition of exogenous herring sperm DNA. Cytofluorometric analysis of cyanocycline A-treat...

The gene encoding an immunologically important 18-kilodalton protein antigen of Mycobacterium leprae has been sequenced, and the amino acid sequence of the antigen has been deduced. The 18-kilodalton antigen is strikingly similar in size and sequence to a family of eucaryotic heat shock proteins.

Aphidicolin, a known inhibitor of eucaryotic deoxyribonucleic acid (DNA) polymerase alpha, efficiently inhibited amplification of ribosomal DNA during oogenesis in Xenopus laevis. DNA polymerase alpha, but not DNA polymerase gamma, as isolated from ovaries, was sensitive to aphidicolin. DNA polymerase beta was not detectable in Xenopus ovary extracts. Therefore, DNA polymerase alpha plays a maj...

interferon is a protein secreted by eucaryotic cells following stimulation by viruses, bacteria, and many other immunogenes. recent medical studies indicate that interferons have effective role in the treatment of virus infections, immunodeficiency and certain types of cancer such as hairy cell leukaemia (hcl). the aim of the present study is to apply yeast strain for secreting human ifnα2b fol...

Centromeres are essential components of eucaryotic chromosomes. In budding yeast, up to now, 15 of the 16 centromere DNAs have been isolated. Here we report the functional isolation and characterization of CEN8, the last of the yeast centromeres missing. The centromere consensus sequence for the 16 chromosomes in this organism is presented.

Bacterial tRNA-guanine transglycosylase (Tgt) catalyses the exchange of the genetically encoded guanine at the wobble position of tRNAs(His,Tyr,Asp,Asn) by the premodified base preQ1, which is further converted to queuine at the tRNA level. As eucaryotes are not able to synthesise queuine de novo but acquire it through their diet, eucaryotic Tgt directly inserts the hypermodified base into the ...