A bacterial cell-cell communication signal with cross-kingdom structural analogues.
Extracellular signals are the key components of microbial cell-cell communication systems. This report identified a diffusible signal factor (DSF), which regulates virulence in Xanthomonas campestris pv. campestris, as cis-11-methyl-2-dodecenoic acid, an alpha,beta unsaturated fatty acid. Analysis of DSF derivatives established the double bond at the alpha,beta positions as the most important structural feature for DSF biological activity. A range of bacterial pathogens, including several Mycobacterium species, also displayed DSF-like activity. Furthermore, DSF is structurally and functionally related to farnesoic acid (FA), which regulates morphological transition and virulence by Candida albicans, a fungal pathogen. Similar to FA, which is also an alpha,beta unsaturated fatty acid, DSF inhibits the dimorphic transition of C. albicans at a physiologically relevant concentration. We conclude that alpha,beta unsaturated fatty acids represent a new class of extracellular signals for bacterial and fungal cell-cell communications. As prokaryote-eukaryote interactions are ubiquitous, such cross-kingdom conservation in cell-cell communication systems might have significant ecological and economic importance.
Wang
Lian-Hui
LH
Institute of Molecular and Cell Biology, 30 Medical Drive, Singapore 117609.
He
Yawen
Y
Gao
Yunfeng
Y
Wu
Ji En
JE
Dong
Yi-Hu
YH
He
Chaozu
C
Wang
Su Xing
SX
Weng
Li-Xing
LX
Xu
Jin-Ling
JL
Tay
Leng
L
Fang
Rong Xiang
RX
Zhang
Lian-Hui
LH
D001426:Bacterial Proteins / Q000737:chemistry / Q000378:metabolism; D002176:Candida albicans / Q000378:metabolism; D002450:Cell Communication / Q000502:physiology*; D005227:Fatty Acids / Q000737:chemistry / Q000378:metabolism*; D015394:Molecular Structure; D016959:Xanthomonas campestris / Q000378:metabolism / Q000472:pathogenicity*
D001426:Bacterial Proteins; D005227:Fatty Acids