The gene order around
amyE+ and
aroI+ of the
B. subtilis chromosomal DNA is
lint-tmrA-amyR-amyE-tmrB-aroI (
J. Bacteriol.,
136: 818-821, 1978). After
EcoRI-digestion of the DNA,
tmrB and
aroI+ were included
in one DNA fragment but
amyE+ was not. The
tmrB aroI+ DNA fragment generated by
EcoRI-digestion of the chromosomal DNA from
B. subtilis B8 was cloned in a temperate
B. subtilis phage ρ11 genome. The molecular size of the
EcoRI-insert containing
tmrB and
aroI+ in the constructed transducing phage genome was 5.14kb. The fragment was recloned in
E. coli vector systems, λgtWES and pBR322. The recombinant plasmid was designated as pTUE1.
The
tmrB aroI+ DNA fragment generated by
EcoRI-digestion of the chromosomal DNA from
B. subtilis T2N26, an ultrahyper α-amylase producing strain, was directly cloned in another vector system, charon 4A, using [
32P]-labeled pTUE1 as a probe. The molecular size of the
tmrB aroI+ fragment inserted in the recombinant phage (λ144A) genome was 11.7kb. Southern hybridization analysis using the two
tmrB aroI+ DNA fragments showed that the molecular size of the
EcoRI fragments from the B8 and T2N26 chromosomal DNA were 13.5kb and 11.7kb, respectively. The physical map of the
aroI+ gene regions was differerent between the B8 T2N26 chromosomal DNA. The physical maps of the
EcoRI-fragments containing the
tmrB aroI+ genes of pTUE1 and the B8 chromosomal DNA were quite different but they hybridized. The small molecular size of the DNA fragment from pTUE1 seemed to be caused by deletion(s) which might have occurred at the construction and stabilization of the
tmrB aroI+ genes in the ρ11 genome.
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