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V Paces

Publications and source records attributed to V Paces.

At least 55 records · Page 3Linked to original sources

Nucleotide sequence of the major early region of Bacillus subtilis phage PZA, a close relative of phi 29.

The 5200-bp nucleotide sequence of the major early region of bacteriophage PZA has been determined. Open reading frames (ORFs) and potential transcriptional and translational regulatory signals were found in this region. The sequence was compared with the known sequence of the homologous region of the closely related phage phi 29 (Yoshikawa and Ito, 1982). This comparison permitted a more accurate assignment of several ORFs and regulatory signals.

Amino Acid Sequence↗

Cloning and expression in Escherichia coli of the synthetic proenkephalin analogue gene.

Enkephalins are pentapeptides with opioid activity that have been found in brain and other neural tissues. They are released by proteolytic processing of the proenkephalin, which contains several enkephalin sequences each flanked by pairs of basic amino acid (aa) residues. We have constructed an artificial variant of the proenkephalin gene by concatenation of synthetic oligodeoxynucleotides (oligo) coding for Met-enkephalin preceded by two arginines. One of the resulting structures, containing eleven enkephalin sequences separated by pairs of arginine codons, was cloned in the expression vector pRE31. The biological activity of enkephalin was detected after the digestion of the isolated plasmid-coded protein with trypsin and carboxypeptidase B. The product of the synthetic gene may thus serve as a defined simplified substrate for the study of the not yet fully understood enzymatic mechanisms of proenkephalin processing.

Animals↗

Comparison of Bacillus subtilis phages PZA, phi 29 and phi 15.

Morphologically identical phages PZA, PZE , phi 29, and phi 15 can be distinguished by the neutralization test with rabbit antisera and by host range specificity. Each member of this phage group contains 18 kb double-stranded linear DNA carrying proteins covalently attached to its 5' ends. Physical maps of their DNA constructed with the use of restriction endonucleases EcoRI, HpaI, HindIII, BspRI, and XbaI and DNA-DNA hybridization experiments show a closer relationship between phi 29 and PZE than between phi 29 and phi 15 or phi 29 and PZA. phi 15 is closer to PZA than to phi 29. This conclusion is supported by analysis of differential denaturation profiles of the phage DNAs. Sequencing of selected parts of phi 29 and PZA DNAs reveals 93% homology with a preference for synonymous base replacements (silent mutations) randomly distributed in the coding regions. Using promoter-probe plasmid pPV33 -H the region functioning as a promoter in E. coli was localized on the smallest EcoRI fragment of PZA and phi 29 DNAs. Comparison of the nucleotide sequence of this region with known promoters of B. subtilis shows extensive homologies with at least two types of promoters of different specificities, namely those recognized by factors sigma 28 of B. subtilis and sigma gp28 of phage SPO1 . These promoter-like regions overlap and the whole sequence is conserved in both phages.

Bacillus subtilis↗