Biosynthesis of Amphi-enterobactin Siderophores by Vibrio harveyi BAA-1116: Identification of a Bifunctional Nonribosomal Peptide Synthetase Condensation Domain
Biosynthesis of Amphi-enterobactin Siderophores by Vibrio harveyi BAA-1116: Identification of a Bifunctional Nonribosomal Peptide Synthetase Condensation Domain
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DOI：
10.1021/ja5019942
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发表时间：
2014-04-16
影响因子：
15
通讯作者：
Butler, Alison
中科院分区：
文献类型：
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作者：
Zane, Hannah K.;Naka, Hiroaki;Butler, Alison
哈维氏弧菌BAA-1116的基因组含有一个非核糖体肽合成酶（NRPS）基因簇（aebA-F），类似于肠杆菌素，但不产生肠杆菌素。预测编码长链脂肪酸CoA连接酶（FACL）的基因，类似于参与酰基肽生物合成的酶，距离推定的肠杆菌素样生物合成基因簇（aebG）15 kb。该FACL基因与肠杆菌素样合成酶的接近表明哈维氏弧菌可能产生两亲性肠杆菌素样铁载体。从哈氏弧菌（V. harveyi）的菌体沉淀中分离出一组由三-2，3-二羟基苯甲酰基-L-丝氨酸和酰基-L-丝氨酸的环状内酯组成的8种双肠杆菌素铁载体，并对其结构进行了测定。FACL敲除突变体Δ aebC哈维氏弧菌和NRPS敲除突变体Δ aebF哈维氏弧菌不产生双端肠杆菌素。在大肠杆菌中异源表达并在体外重建了两种肠杆菌素生物合成机制，表明AebF的缩合结构域具有独特的活性，催化两种不同的缩合反应。
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, Delta aebC V. harveyi, and the NRPS knockout mutant, Delta aebF 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.