Discovery of unique lanthionine synthetases reveals new mechanistic and evolutionary insights.
Discovery of unique lanthionine synthetases reveals new mechanistic and evolutionary insights.
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独特的羊毛硫氨酸合成酶的发现揭示了新的机制和进化见解。
DOI：
10.1371/journal.pbio.1000339
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发表时间：
2010-03-23
期刊：
影响因子：
9.8
通讯作者：
van der Donk WA
中科院分区：
文献类型：
--
作者：
Goto Y;Li B;Claesen J;Shi Y;Bibb MJ;van der Donk WA
一类新的羊毛硫氨酸合成酶的鉴定为环肽生物合成的机制和进化提供了深入的了解。羊毛硫抗生素合成酶是一种重要的生物催化剂，通过重复利用两个简单的翻译后修饰反应（Ser/Thr残基脱水和Cys巯基分子内加成）产生具有多种生物活性的构象受限肽。由于先前报道的lantibiotic合成酶与任何其他已知的蛋白质家族没有明显的同源性，因此这些酶的分子机制和进化起源是未知的。在这项研究中，我们提出了一种新的类lanthiolate合成酶，称为LanL，由三个不同的催化结构域，并证明在体外酶活性的家庭成员从委内瑞拉链霉菌。单独表达和纯化的结构域的分析表明，LanL酶通过蛋白激酶结构域对Ser/Thr残基的磷酸化和随后的磷酸化Ser/Thr裂解酶结构域对磷酸的消除来安装脱氢氨基酸。后者与发现于多种病原菌中的磷酸苏氨酸裂解酶具有序列同源性，所述病原菌是有丝分裂原活化蛋白激酶的宿主。然后，LanC样环化酶结构域催化Cys残基添加至C10氨基酸以形成特征性硫醚环。我们提出LanL酶已经从独立的蛋白质Ser/Thr激酶、磷酸化Ser/Thr裂解酶和催化硫醇烷基化的酶进化而来。我们还表明，所有三个途径的基因，含羊毛硫氨酸肽是广泛存在于自然界。考虑到形成含羊毛硫氨酸的多环肽的显著效率和后者对其同源细胞靶标的高度特异性，（至少）三个不同家族的多肽序列已经进化以获得这种结构和功能多样的化合物可能并不令人惊讶。许多细菌产生环状肽，其与线性肽相比具有改善的生物活性，包括更高的稳定性。含羊毛硫氨酸的肽就是这样一组，该组的不同成员具有抗生素、抗炎和抗病毒活性。例如，一种叫做乳酸链球菌素的含有羊毛硫氨酸的肽被用来保护食品免受有害细菌的侵害。先前已经描述了含羊毛硫氨酸的肽的生物合成的两种不同途径。通过比较细菌基因组的DNA序列，我们揭示了第三种生物合成途径，进一步了解这些环肽的生物合成途径是如何演变的。我们的特点是在土壤细菌委内瑞拉链霉菌中的第三种途径中使用的新型羊毛硫氨酸合成酶，并表明纯化的酶催化将线性肽转化为具有多个环的肽所需的化学反应。这第三种生物合成途径的发现拓宽了工程化新的含羊毛硫氨酸的肽用于人类治疗的潜在用途的范围。
Identification of a new class of lanthionine synthetases provides insight into the mechanism and evolution of cyclic peptide biosynthesis. Lantibiotic synthetases are remarkable biocatalysts generating conformationally constrained peptides with a variety of biological activities by repeatedly utilizing two simple posttranslational modification reactions: dehydration of Ser/Thr residues and intramolecular addition of Cys thiols to the resulting dehydro amino acids. Since previously reported lantibiotic synthetases show no apparent homology with any other known protein families, the molecular mechanisms and evolutionary origin of these enzymes are unknown. In this study, we present a novel class of lanthionine synthetases, termed LanL, that consist of three distinct catalytic domains and demonstrate in vitro enzyme activity of a family member from Streptomyces venezuelae. Analysis of individually expressed and purified domains shows that LanL enzymes install dehydroamino acids via phosphorylation of Ser/Thr residues by a protein kinase domain and subsequent elimination of the phosphate by a phosphoSer/Thr lyase domain. The latter has sequence homology with the phosphothreonine lyases found in various pathogenic bacteria that inactivate host mitogen activated protein kinases. A LanC-like cyclase domain then catalyzes the addition of Cys residues to the dehydro amino acids to form the characteristic thioether rings. We propose that LanL enzymes have evolved from stand-alone protein Ser/Thr kinases, phosphoSer/Thr lyases, and enzymes catalyzing thiol alkylation. We also demonstrate that the genes for all three pathways to lanthionine-containing peptides are widespread in Nature. Given the remarkable efficiency of formation of lanthionine-containing polycyclic peptides and the latter's high degree of specificity for their cognate cellular targets, it is perhaps not surprising that (at least) three distinct families of polypeptide sequences have evolved to access this structurally and functionally diverse class of compounds. Many bacteria generate cyclic peptides, which have improved biological activities compared to linear peptides, including higher stability. Lanthionine-containing peptides are one such group, and different members of this group have antibiotic, anti-inflammatory, and anti-viral activities. For example, one lanthionine-containing peptide called nisin has been used to protect food items from harmful bacteria. Two different pathways for the biosynthesis of lanthionine-containing peptides have been described previously. By comparing the DNA sequences of bacterial genomes we reveal a third biosynthetic route that provides further insight into how the biosynthetic pathways for these cyclic peptides have evolved. We characterized the novel lanthionine synthetase utilized in this third pathway in the soil bacterium Streptomyces venezuelae and show that the purified enzyme catalyzes the chemical reactions necessary to turn a linear peptide into a peptide with multiple rings. The discovery of this third biosynthetic pathway widens the scope for the engineering of new lanthionine-containing peptides for potential use in human therapeutics.
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影响因子：
14.9
作者：
Cole JR;Wang Q;Cardenas E;Fish J;Chai B;Farris RJ;Kulam-Syed-Mohideen AS;McGarrell DM;Marsh T;Garrity GM;Tiedje JM
通讯作者：
Tiedje JM
影响因子：
16.8
作者：
Chen, Linjie;Wang, Huayi;Chai, Jijie
通讯作者：
Chai, Jijie
影响因子：
14.8
作者：
Oman TJ;van der Donk WA
通讯作者：
van der Donk WA
影响因子：
4.8
作者：
Li, Bo;van der Donk, Wilfred A.
通讯作者：
van der Donk, Wilfred A.
DOI：
10.1073/pnas.0606088103
发表时间：
2006-11-14
影响因子：
11.1
作者：
McClerren, Amanda L.;Cooper, Lisa E.;van der Donk, Wilfred A.
通讯作者：
van der Donk, Wilfred A.