Send to

Choose Destination
FEMS Microbiol Lett. 1999 Oct 1;179(1):53-9.

A transposon insertion in the gumG homologue of Xanthomonas oryzae pv. oryzae causes loss of extracellular polysaccharide production and virulence.

Author information

Centre for Cellular and Molecular Biology, Uppal Road, Hyderabad, India.


Xanthomonas oryzae pv. oryzae causes a serious disease of rice called bacterial leaf blight. It produces copious amounts of extracellular polysaccharide (EPS). An EPS- and virulence-deficient mutant of X. oryzae pv. oryzae was isolated by Tn5 mutagenesis. The mutant allele in this strain was cloned by transposon tagging in the Escherichia coli vector pBluescript and the DNA sequences flanking the transposon insertion site were determined. Computer-based similarity searches in the DNA database using the BLAST algorithm showed these sequences to be 78% identical at the nucleotide level to a gene, gumG, in the gum cluster, which is required for EPS biosynthesis in Xanthomonas campestris pv. campestris. A 36-kb X. oryzae pv. oryzae genomic clone containing the putative EPS biosynthetic gene cluster of X. oryzae pv. oryzae restored both EPS production and virulence proficiency to the gumGXo::Tn5 mutant. The results suggest that EPS is an important virulence factor of X. oryzae pv. oryzae.

[Indexed for MEDLINE]
Free full text

Supplemental Content

Full text links

Icon for Silverchair Information Systems Icon for Wiley
Loading ...
Support Center