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B S Vold

Publications and source records attributed to B S Vold.

41 records · Page 3Linked to original sources
PubMed1968

Changes in soluble RNA and ribonuclease activity during germination of wheat.

Gross changes in protein and nucleic acid were studied in germinating wheat seeds. The nucleic acid fraction was separated on columns of methylated albumin-keiselguhr. It was found that more than 50% of the transfer RNA was lost from the embryo in the first 10 to 15 hours of germination. This was followed by a period of rapid resynthesis of transfer RNA, to the normal level at about 20 hours. The decline and increase in transfer RNA was accompanied by a change in the ratios of certain amino acid acceptor species. Evidence is also presented that an embryo ribonuclease is lost during the first 10 to 15 hours, followed by the appearance of a second seedling ribonuclease between 15 and 30 hours of germination.

RNA, Transfer↗
PubMedDate not supplied

Activity of ribosomal and tRNA promoters of Bacillus subtilis during sporulation.

The rrnB operon in Bacillus subtilis includes 21 tRNA genes downstream of the ribosomal genes. In addition to the dual promoters upstream of these ribosomal genes, a second promoter is found within the tRNA gene region. In this study, these two promoter regions were inserted before the lacZ gene and each was integrated as a single-copy into the B subtilis chromosome to examine their activity during sporulation. Both promoters exhibited similar strength and temporal downregulation from vegetative growth through t3 of sporulation. At t3, transcription from both promoters was approximately 20% of that in logarithmic growth. No obvious function of the second promoter is evident except to boost transcription of downstream genes. This function may be important because the ribosomal promoters of rrnB are weak relative to other ribosomal promoters. For instance, the rrnO promoters were much stronger than the rrnB ribosomal promoters and considerably more active at t3. Thus, all ribosomal promoters are not of the same strength nor are they transcriptionally downregulated to the same extent during sporulation. However, both the rRNA and tRNA promoters in the rrnB operon are similar in strength and downregulation.

Bacillus subtilis↗