Small, stable shuttle vectors for use in Xanthomonas.

Plasmids from three broad-host-range (bhr) incompatibility groups (Inc) were evaluated for use as cloning vectors in Xanthomonas campestris pv. malvacearum (Xcm), the causal agent of bacterial blight of cotton. The IncP vectors pLAFR3 and pVK102 could not be introduced into Xcm at a significant frequency (less than 1 x 10(-10] and IncQ vectors such as pKT210 were unstable in their maintenance and tended to delete cloned inserts.

Nucleotide sequence of the transcription unit containing the aroL and aroM genes from Escherichia coli K-12.

The nucleotide sequence of 2,021 base pairs (bp) of DNA containing the Escherichia coli aroLM operon was determined, and the coding regions of both aroL and aroM were identified. The 501-bp intercistronic region between aroL and aroM contains an open reading frame which might encode a 63-residue protein. Northern blots with RNA from strains carrying multicopy aroL+ plasmids detected one longer (2,000-base) and two shorter (950- and 1,100-base) transcripts which contained aroL.

Genetic and molecular analysis of aroL, the gene for shikimate kinase II in Escherichia coli K-12.

The gene aroL in Escherichia coli K-12, specifying shikimate kinase II, was contransduced with proC at a frequency of 99%. The gene order is lac proC aroL. A 2.