title: 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.
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.
authors: Division of Biosphere Science, Graduate School of Environmental Science, Hokkaido University, Sapporo, Japan. washi@ees.hokudai.ac.jp
authors: Kenji
authors: K
authors: Washio
authors: Siew Ping
authors: SP
authors: Lim
authors: Niran
authors: N
authors: Roongsawang
authors: Masaaki
authors: M
authors: Morikawa
mesh_terms: D000595:Amino Acid Sequence; D001483:Base Sequence; D004251:DNA Transposable Elements / Q000235:genetics; D056426:Genetic Loci / Q000235:genetics; D006159:Guanosine Tetraphosphate / Q000378:metabolism*; D055666:Lipopeptides / Q000096:biosynthesis*; D008969:Molecular Sequence Data; D010456:Peptides, Cyclic / Q000096:biosynthesis*; D017434:Protein Structure, Tertiary; D011549:Pseudomonas / Q000201:enzymology / Q000235:genetics* / Q000378:metabolism*; D011755:Pyrophosphatases / Q000737:chemistry* / Q000235:genetics* / Q000378:metabolism; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D017384:Sequence Deletion; D014158:Transcription, Genetic / Q000235:genetics; D014170:Transformation, Genetic
chemical_list: D004251:DNA Transposable Elements; D055666:Lipopeptides; D010456:Peptides, Cyclic; D012333:RNA, Messenger; C083714:arthrofactin; D006159:Guanosine Tetraphosphate; C027627:guanosine-3',5'-bis(diphosphate) 3'-pyrophosphatase; D011755:Pyrophosphatases