The Multiple DSF-family QS Signals are Synthesized from Carbohydrate and Branched-chain Amino Acids via the FAS Elongation Cycle.
Members of the diffusible signal factor (DSF) family are a novel class of quorum sensing (QS) signals in diverse Gram-negative bacteria. Although previous studies have identified RpfF as a key enzyme for the biosynthesis of DSF family signals, many questions in their biosynthesis remain to be addressed. In this study with the phytopathogen Xanthomonas campestris pv. campestris (Xcc), we show that Xcc produces four DSF-family signals (DSF, BDSF, CDSF and IDSF) during cell culture, and that IDSF is a new functional signal characterized as cis-10-methyl-2-dodecenoic acid. Using a range of defined media, we further demonstrate that Xcc mainly produces BDSF in the presence of carbohydrates; leucine and valine are the primary precursor for DSF biosynthesis; isoleucine is the primary precursor for IDSF biosynthesis. Furthermore, our biochemical analyses show that the key DSF synthase RpfF has both thioesterase and dehydratase activities, and uses 3-hydroxydedecanoyl-ACP as a substrate to produce BDSF. Finally, our results show that the classic fatty acid synthesis elongation cycle is required for the biosynthesis of DSF-family signals. Taken all together, these findings establish a general biosynthetic pathway for the DSF-family quorum sensing signals.
State Key Laboratory of Microbial Metabolism, School of Life Sciences &Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, China.
Lian
L
Zhou
College of Life Sciences, South China Agricultural University, Guangzhou 510650, China.
Yonghong
Y
Yu
State Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Huazhong Agricultural University, Wuhan, 430070, China.
Xiping
X
Chen
State Key Laboratory of Microbial Metabolism, School of Life Sciences &Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, China.
Abdelgader Abdeen
AA
Diab
State Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Huazhong Agricultural University, Wuhan, 430070, China.
Lifang
L
Ruan
State Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Huazhong Agricultural University, Wuhan, 430070, China.
Jin
J
He
College of Life Sciences, South China Agricultural University, Guangzhou 510650, China.
Haihong
H
Wang
State Key Laboratory of Microbial Metabolism, School of Life Sciences &Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, China.
Ya-Wen
YW
He
D000597:Amino Acids, Branched-Chain / Q000494:pharmacology*; D001426:Bacterial Proteins / Q000378:metabolism; D053898:Biosynthetic Pathways / Q000187:drug effects; D002241:Carbohydrates / Q000494:pharmacology*; D002569:Cerulenin / Q000494:pharmacology; D004058:Diffusion; D005227:Fatty Acids / Q000096:biosynthesis*; D005798:Genes, Bacterial; D008954:Models, Biological; D053038:Quorum Sensing / Q000187:drug effects*; D013869:Thiolester Hydrolases / Q000378:metabolism; D016959:Xanthomonas campestris / Q000187:drug effects / Q000235:genetics / Q000254:growth & development
D000597:Amino Acids, Branched-Chain; D001426:Bacterial Proteins; D002241:Carbohydrates; D005227:Fatty Acids; D002569:Cerulenin; D013869:Thiolester Hydrolases; C018748:oleoyl-(acyl-carrier-protein) hydrolase