Construction of a promoter-probe vector for a Bacillus subtilis host by using the trpD+ gene of Bacillus amyloliquefaciens

Multiple and tandemly arranged promoters of the cell wall protein gene operon in Bacillus brevis 47

The genes encoding the major cell wall proteins, middle wall protein and outer wall protein, of Bacillus brevis 47 constitute a cotranscriptional unit (cwp [cell wall protein gene] operon). Primer extension assay of cwp operon transcripts showed the existence of six different 5' ends. This confirmed the results of the previous S1 nuclease protection assay and suggested the existence of several tandemly arranged promoters in the 5' region of the cwp operon. Promoter probe vectors carrying the Bacillus licheniformis alpha-amylase gene were constructed and used for deletion analysis of the 5' region. Three (P1, P2, and P3) of the six suggested promoters were shown to be located within three distinct fragments derived from the 5' region. The -35 and -10 regions of the P1 and P3 promoters resemble the consensus sequence recognized by the sigma-43-type RNA polymerase of Bacillus subtilis. The P2 promoter resembles only the consensus sequence in the -10 region. The P1 and P3 promoters were used to the same extents in Bacillus subtilis as in B. brevis, whereas the P2 promoter was used much less frequently in B. subtilis than in B. brevis. The P2 promoter is used constitutively in B. brevis 47 at all stages of growth, whereas P3 is used only at the exponential phase of growth. P2 could be a promoter of an unknown type that is preferentially used in B. brevis and might be responsible for the constitutive synthesis and secretion of the cell wall proteins into the medium at the stationary phase of growth.

Isolation and characterization of a 2.2-kb operon preceding the alpha-amylase gene of Bacillus amyloliquefaciens

A DNA region of 2.8 X 10(3) base pairs (2.8 kb) upstream of the Bacillus amyloliquefaciens alpha-amylase gene has been isolated. This DNA gave rise to a 2.2-kb transcript. The 3' end of the transcript was mapped with S1 nuclease and shown to terminate 49 base pairs upstream of the -35 region of the alpha-amylase promoter. In B. subtilis minicells this 2.2-kb transcript coded for three different polypeptides, thus indicating a polycistronic operon-type structure. The location and the order of the polypeptides were established using DNA deletions. The joining of the 2.2-kb operon to the downstream alpha-amylase gene in the plasmid pUB110 did not have any significant effect on the level of expression of the alpha-amylase.

Construction of high, intermediate and low-copy-number promoter-probe plasmids for Bacillus subtilis

We constructed promoter-probe plasmids for Bacillus subtilis based on the promoterless gene for penicillinase (penP) of Bacillus licheniformis. A Bacillus stearothermophilus DNA fragment, which contained translational stop codons for all three reading frames and transcription terminators of the alpha-amylase gene, was inserted upstream from the Shine-Dalgarno sequence for the penP gene. A low-copy-number plasmid (about 10 copies per chromosome), pPF101, carried tetracycline-resistance gene, whereas another high-copy-number plasmid (about 55 copies per chromosome), pPF201, conferred resistance to kanamycin. The intermediate-copy-number plasmids (about 20 copies per chromosome), pPF001, pPF002, pPF011 and pPF012, conferred chloramphenicol resistance to both B. subtilis and Escherichia coli. Vector plasmids, pPF011 and pPF012, were provided with single cloning sites for BamHI, SacI, SmaI and XbaI upstream from the protein coding region of penP, whereas other plasmids contained only unique BamHI cloning sites. The applicability of these plasmids was demonstrated by cloning a promoter for the alpha-amylase gene.

Nucleotide sequence of the Bacillus subtilis tryptophan operon

In Bacillus subtilis, tryptophan biosynthesis is one of the most thoroughly characterized biosynthetic pathways. Recombinant DNA methodology has permitted a rapid characterization of the tryptophan (trp) gene cluster at the molecular level. In this report the nucleotide sequence of the six structural genes together with the intercistronic regions and flanking regulatory regions are presented.