Previous Article | Next Article ![]()
J. Bacteriol., 02 1996, 625-632, Vol 178, No. 3
SR Monday and NL Schiller
Previous studies localized an alginate lyase gene (algL) within the
alginate biosynthetic gene cluster at 34 min on the Pseudomonas aeruginosa
chromosome. Insertion of a Tn501 polar transposon in a gene (algX) directly
upstream of algL in mucoid P. aeruginosa FRD1 inactivated expression of
algX, algL, and other downstream genes, including algA. This strain is
phenotypically nonmucoid; however, alginate production could be restored by
complementation in trans with a plasmid carrying all of the genes
inactivated by the insertion, including algL and algX. Alginate production
was also recovered when a merodiploid that generated a complete alginate
gene cluster on the chromosome was constructed. However, alginate
production by merodiploids formed in the algX::Tn501 mutant using an
alginate cluster with an algL deletion was not restored to wild-type levels
unless algL was provided on a plasmid in trans. In addition,
complementation studies of Tn501 mutants using plasmids containing specific
deletions in either algL or algX revealed that both genes were required to
restore the mucoid phenotype. Escherichia coli strains which expressed algX
produced a unique protein of approximately 53 kDa, consistent with the gene
product predicted from the DNA sequencing data. These studies demonstrate
that AlgX, whose biochemical function remains to be defined, and AlgL,
which has alginate lyase activity, are both involved in alginate production
by P. aeruginosa.
Copyright © 1996, American Society for Microbiology
Alginate synthesis in Pseudomonas aeruginosa: the role of AlgL (alginate lyase) and AlgX
Division of Biomedical Sciences, University of California, Riverside 92521-0121, USA.
This article has been cited by other articles:
Copyright © 2009 by the American Society for Microbiology. For an alternate route to Journals.ASM.org, visit: http://intl-journals.asm.org | More Info»