Biosynthesis of amphi-enterobactin siderophores by Vibrio harveyi BAA-1116: identification of a bifunctional nonribosomal peptide synthetase condensation domain.
The genome of Vibrio harveyi BAA-1116 contains a nonribosomal peptide synthetase (NRPS) gene cluster (aebA-F) resembling that for enterobactin, yet enterobactin is not produced. A gene predicted to encode a long-chain fatty acid CoA ligase (FACL), similar to enzymes involved in the biosynthesis of acyl peptides, resides 15 kb away from the putative enterobactin-like biosynthetic gene cluster (aebG). The proximity of this FACL gene to the enterobactin-like synthetase suggested that V. harveyi may produce amphiphilic enterobactin-like siderophores. Extraction of the bacterial cell pellet of V. harveyi led to the isolation and structure determination of a suite of eight amphi-enterobactin siderophores composed of the cyclic lactone of tris-2,3-dihydroxybenzoyl-L-serine and acyl-L-serine. The FACL knockout mutant, ΔaebG V. harveyi, and the NRPS knockout mutant, ΔaebF V. harveyi, do not produce amphi-enterobactins. The amphi-enterobactin biosynthetic machinery was heterologously expressed in Escherichia coli and reconstituted in vitro, demonstrating the condensation domain of AebF has unique activity, catalyzing two distinct condensation reactions.
Department of Chemistry and Biochemistry, University of California , Santa Barbara, California 93106-9510, United States.
Hannah K
HK
Zane
Hiroaki
H
Naka
Federico
F
Rosconi
Moriah
M
Sandy
Margo G
MG
Haygood
Alison
A
Butler
D002851:Chromatography, High Pressure Liquid; D004758:Enterobactin / Q000096:biosynthesis*; D010453:Peptide Synthases / Q000378:metabolism*; D017262:Siderophores / Q000096:biosynthesis*; D014733:Vibrio / Q000378:metabolism*
D017262:Siderophores; D004758:Enterobactin; D010453:Peptide Synthases