Quorum sensing and the LysR-type transcriptional activator ToxR regulate toxoflavin biosynthesis and transport in Burkholderia glumae

Kim, J; Kim, JG; Kang, Y; Jang, JY; Jog, GJ; Lim, JY; Kim, S; Suga, H; Nagamatsu, T; Hwang, I

HERO ID

7756038

Reference Type

Journal Article

Year

2004

Language

English

PMID

15522077

HERO ID 7756038
In Press No
Year 2004
Title Quorum sensing and the LysR-type transcriptional activator ToxR regulate toxoflavin biosynthesis and transport in Burkholderia glumae
Authors Kim, J; Kim, JG; Kang, Y; Jang, JY; Jog, GJ; Lim, JY; Kim, S; Suga, H; Nagamatsu, T; Hwang, I
Journal Molecular Microbiology
Volume 54
Issue 4
Page Numbers 921-934
Abstract Burkholderia glumae BGR1 produces a broad-host range phytotoxin, called toxoflavin, which is a key pathogenicity factor in rice grain rot and wilt in many field crops. Our molecular and genetic analyses of toxoflavin-deficient mutants demonstrated that gene clusters for toxoflavin production consist of four transcriptional units. The toxoflavin biosynthesis genes were composed of five genes, toxA to toxE, as Suzuki et al. (2004) reported previously. Genes toxF to toxI, which are responsible for toxoflavin transport, were polycistronic and similar to the genes for resistance-nodulation-division (RND) efflux systems. Using Tn3-gusA reporter fusions, we found that ToxR, a LysR-type regulator, regulates both the toxABCDE and toxFGHI operons in the presence of toxoflavin as a coinducer. In addition, the expression of both operons required a transcriptional activator, ToxJ, whose expression is regulated by quorum sensing. TofI, a LuxI homologue, was responsible for the biosynthesis of both N-hexanoyl homoserine lactone and N-octanoyl homoserine lactone (C8-HSL). C8-HSL and its cognate receptor TofR, a LuxR homologue, activated toxJ expression. This is the first report that quorum sensing is involved in pathogenicity by the regulation of phytotoxin biosynthesis and its transport in plant pathogenic bacteria.
Doi 10.1111/j.1365-2958.2004.04338.x
Pmid 15522077
Wosid WOS:000224858300007
Is Certified Translation No
Dupe Override No
Is Public Yes
Language Text English