Tn, a Carrier of Tn Family Transposons, Occurs in the Chromosome and in a Genomic Island of Clinical Strains.

Transposons of the accessory gene pool contribute to phenotype and to genome plasticity. We studied local strains to ascertain the encroachment of -type site hunter transposons into clinical settings and their associations with other functional modules. Five different Tn family transposons were detected, all chromosomal.

Embedded elements in the IncPbeta plasmids R772 and R906 can be mobilized and can serve as a source of diverse and novel elements.

IncP plasmids are important contributors to bacterial adaptation. Their phenotypic diversity is due largely to accessory regions located in one or two specific parts of the plasmid. The accessory regions are themselves diverse, as judged from sequenced plasmids mostly isolated from non-clinical sources.

Mercury(II)-resistance transposons Tn502 and Tn512, from Pseudomonas clinical strains, are structurally different members of the Tn5053 family.

The mercury(II)-resistance transposons Tn502 and Tn512 were sequenced and shown to be members of the Tn5053 family. They are currently the sole representatives from the clinical setting and were obtained from geographically disparate Pseudomonas aeruginosa strains. The family is comprised of six novel transposons that display genetic and structural variability that has arisen in different ways.

Tn502 and Tn512 are res site hunters that provide evidence of resolvase-independent transposition to random sites.

In this study, we report on the transposition behavior of the mercury(II) resistance transposons Tn502 and Tn512, which are members of the Tn5053 family. These transposons exhibit targeted and oriented insertion in the par region of plasmid RP1, since par-encoded components, namely, the ParA resolvase and its cognate res region, are essential for such transposition. Tn502 and, under some circumstances, Tn512 can transpose when par is absent, providing evidence for an alternative, par-independent pathway of transposition.

Topological characterization of an inner membrane (1-->3)-beta-D-glucan (curdlan) synthase from Agrobacterium sp. strain ATCC31749.

The crdS gene of Agrobacterium sp. strain ATCC31749 encodes the curdlan synthase (CrdS) protein based on the homology of the derived CrdS protein sequence with those of beta-glycosyl transferases with repetitive action patterns (Stasinopoulos et al. [1999] Glycobiology, 9, 31-41).

Cloning and characterization of the phosphatidylserine synthase gene of Agrobacterium sp. strain ATCC 31749 and effect of its inactivation on production of high-molecular-mass (1-->3)-beta-D-glucan (curdlan).

Genes involved in the production of the extracellular (1-->3)-beta-glucan, curdlan, by Agrobacterium sp. strain ATCC 31749 were described previously (Stasinopoulos et al., Glycobiology 9:31-41, 1999).