A Truncated Form of SpoT, Including the ACT Domain, Inhibits the Production of Cyclic Lipopeptide Arthrofactin, and Is Associated with Moderate Elevation of Guanosine 3 ‘,5 ‘-Bispyrophosphate Level in Pseudomonas sp MIS38
A Truncated Form of SpoT, Including the ACT Domain, Inhibits the Production of Cyclic Lipopeptide Arthrofactin, and Is Associated with Moderate Elevation of Guanosine 3 ',5 '-Bispyrophosphate Level in Pseudomonas sp MIS38
Hokkaido University; Monash University; Monash University Sunway; National Science & Technology Development Agency - Thailand; National Center Genetic Engineering & Biotechnology (BIOTEC)
Type
Article
Source Title
BIOSCIENCE BIOTECHNOLOGY AND BIOCHEMISTRY
ISSN
0916-8451
Year
2011
Volume
75
Issue
10
Page
1880-1888
Open Access
Bronze
Publisher
TAYLOR & FRANCIS LTD
DOI
10.1271/bbb.110042
Format
PDF
Abstract
Arthrofactin is a biosurfactant produced by Pseudomonas sp. MIS38. We have reported that transposon insertion into spoT (spoT::Tn5) causes moderate accumulation of guanosine 3',5'-bispyrophosphate (ppGpp) and abrogates arthrofactin production. To analyze the linkage of SpoT function and ablation of arthrofactin production, we examined the spoT::Tn5 mutation. The results showed that spoT::Tn5 is not a null mutation, but encodes separate segments of SpoT. Deletion of the 3' region of spoT increased the level of arthrofactin production, suggesting that the C-terminal region of SpoT plays a suppressive role. We evaluated the expression of a distinct segment of SpoT. Forced expression of the C-terminal region that contains the ACT domain resulted in the accumulation of ppGpp and abrogated arthrofactin production. Expression of the C-terminal segment also reduced MIS38 swarming and resulted in extensive biofilm formation, which constitutes the phenocopy of the spoT::Tn5 mutant.
