3-Hydroxypyridine dehydrogenase HpdA is encoded by a novel four-component gene cluster and catalyzes the first step of 3-hydroxypyridine catabolism in Ensifer adhaerens HP1
3-Hydroxypyridine dehydrogenase HpdA is encoded by a novel four-component gene cluster and catalyzes the first step of 3-hydroxypyridine catabolism in Ensifer adhaerens HP1
复制标题
3-羟基吡啶脱氢酶 HpdA 由新型四组分基因簇编码，催化 ensifer adhaerens HP 中 3-羟基吡啶分解代谢的第一步
DOI：
10.1128/aem.01313-20
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发表时间：
2020
影响因子：
4.4
通讯作者：
Lu Zhenmei
中科院分区：
文献类型：
--
作者：
Wang Haixia;Wang Xiaoyu;Ren Hao;Wang Xuejun;Lu Zhenmei
3-羟基吡啶（3 HP）是一种重要的天然吡啶衍生物。黏泥虫HP 1可以利用3 HP作为其生长的唯一碳、氮和能量来源，但负责降解3 HP的基因仍然未知。在本研究中，我们预测了一个基因簇，命名为3 hpd，可能负责3 HP的降解。分析表明，在E. adhaerensHP 1由四组分脱氢酶（HpdA 1A 2A 3A 4）催化并导致2，5-二羟基吡啶（2，5-DHP）的形成。此外，HpdA中的SRPBCC组分作为一个单独的亚基存在，这与其他含SRPBCC的N-杂环芳香族化合物羟化酶不同。结果表明，磷酸烯醇式丙酮酸（PEP）利用蛋白和磷酸二激酶参与了HpdA的活性，并在不同菌株的基因组中发现了基因簇3 hpd。我们的研究结果为进一步了解吡啶衍生物在自然界中的微生物降解提供了新的思路，同时也表明进一步研究发现的具有单独SRPBCC结构域的四组分脱氢酶的起源以及PEP利用蛋白和磷酸二激酶的功能具有重要意义。重要提示3-羟基吡啶是合成药物、除草剂和抗生素的重要组成部分。虽然3-羟基吡啶的微生物降解已经研究了很多年，但其分子机制仍不清楚。在这里，我们表明，3 hpis负责3-羟基吡啶的催化。3 hpd基因簇广泛存在于放线菌、红杆菌、嗜热菌、α-、β-和γ-变形菌中，其遗传结构具有高度的多样性。我们的研究结果提供了新的见解3-羟基吡啶在细菌中的催化剂。
3-Hydroxypyridine (3HP) is an important natural pyridine derivative. Ensifer adhaerens HP1 can utilize 3HP as its sole sources of carbon, nitrogen, and energy to grow, but the genes responsible for the degradation of 3HP remain unknown. In this study, we predicted that a gene cluster, designated3hpd, might be responsible for the degradation of 3HP. The analysis showed that the initial hydroxylation of 3HP inE. adhaerensHP1 was catalyzed by a four-component dehydrogenase (HpdA1A2A3A4) and led to the formation of 2,5-dihydroxypyridine (2,5-DHP). In addition, the SRPBCC component in HpdA existed as a separate subunit, which is different from other SRPBCC-containing molybdohydroxylases acting onN-heterocyclic aromatic compounds. Moreover, the results demonstrated that the phosphoenolpyruvate (PEP)-utilizing protein and pyruvate-phosphate dikinase were involved in the HpdA activity, and the presence of the gene cluster3hpdwas discovered in the genomes of diverse microbial strains. Our findings provide a better understanding of the microbial degradation of pyridine derivatives in nature and indicated that further research on the origin of the discovered four-component dehydrogenase with a separate SRPBCC domain and the function of PEP-utilizing protein and pyruvate-phosphate dikinase might be of great significance.IMPORTANCE3-Hydroxypyridine is an important building block for the synthesis of drugs, herbicides, and antibiotics. Although the microbial degradation of 3-hydroxypyridine has been studied for many years, the molecular mechanisms remain unclear. Here, we show that3hpdis responsible for the catabolism of 3-hydroxypyridine. The3hpdgene cluster was found to be widespread inActinobacteria,Rubrobacteria,Thermoleophilia, andAlpha-,Beta-, andGammaproteobacteria, and the genetic organization of the3hpdgene clusters in these bacteria shows high diversity. Our findings provide new insight into the catabolism of 3-hydroxypyridine in bacteria.