Alginate Synthesis in Mucoid Pseudomonas aeruginosa: a Chromosomal Locus Involved in Control

Abstract

Mucoid variants of Pseudomonas aeruginosa isolated in vitro or in vivo could be classified into two phenotypic groups based on whether alginate was produced on a chemically defined medium. Mucoid strains yielded lowe recombination frequencies than the non-mucoid parent when used as donors in FP2-mediated plate matings. The mucoid characteristic (muc) was co-inherited by a proportion of recombinants selected for the inheritance of chromosomal markers his-5075+ or cys-5605+. The results of further experiments using either a mucoid recipient or a mucoid donor carrying plasmid R68.45 suggested that the control of alginate production in P. aeruginosa involves at least one chromosomal locus.