Characterization of the phosphotransacetylase-acetate kinase pathway for ATP production in Porphyromonas gingivalis
Characterization of the phosphotransacetylase-acetate kinase pathway for ATP production in Porphyromonas gingivalis
复制标题
牙龈卟啉单胞菌中 ATP 产生的磷酸转乙酰酶-乙酸激酶途径的表征
DOI：
10.1080/20002297.2019.1588086
复制
发表时间：
2019
影响因子：
4.5
通讯作者：
Kezuka Yuichiro
中科院分区：
文献类型：
--
作者：
Yoshida Yasuo;Sato Mitsunari;Nonaka Takamasa;Hasegawa Yoshiaki;Kezuka Yuichiro
乙酰磷酸（AcP）通常由乙酰辅酶A通过磷酸转乙酰酶（Pta）产生，随后在乙酸激酶（Ack）催化下与ADP反应产生ATP。牙龈卟啉单胞菌产生ATP的机制尚不清楚。本研究的目的是探索该微生物中Pta-Ack途径的分子基础。Pta和Ack from P. gingivalisATCC 33277进行酶和结构表征。结构和突变分析表明，Pta是一种二聚体，每个亚基中有两个底物结合位点。Ack也是二聚体，在每个亚基中具有催化裂缝，并且结构分析表明在催化期间打开和关闭裂缝的戏剧性结构域运动。由Ack形成ATP经由顺序机制进行。逆转录PCR分析表明，thepta（PGN_1179）和ack（PGN_1178）基因串联在基因组中，以操纵子的形式共转录。灭活ptaorackin P. gingivalisby同源重组只有在失活的基因以反式表达时才能成功，因此，pta和ack基因都是该微生物所必需的。本文报道的Pta-Ack通路的见解将有助于理解能量获取在P。牙龈炎
Acetyl phosphate (AcP) is generally produced from acetyl coenzyme A by phosphotransacetylase (Pta), and subsequent reaction with ADP, catalyzed by acetate kinase (Ack), produces ATP. The mechanism of ATP production inPorphyromonas gingivalisis poorly understood. The aim of this study was to explore the molecular basis of the Pta-Ack pathway in this microorganism. Pta and Ack fromP. gingivalisATCC 33277 were enzymatically and structurally characterized. Structural and mutational analyses suggest that Pta is a dimer with two substrate-binding sites in each subunit. Ack is also dimeric, with a catalytic cleft in each subunit, and structural analysis indicates a dramatic domain motion that opens and closes the cleft during catalysis. ATP formation by Ack proceeds via a sequential mechanism. Reverse transcription-PCR analysis demonstrated that thepta(PGN_1179) andack(PGN_1178) genes, tandemly located in the genome, are cotranscribed as an operon. Inactivation ofptaorackinP. gingivalisby homologous recombination was successful only when the inactivated gene was expressedin trans. Therefore, bothptaandackgenes are essential for this microorganism. Insights into the Pta-Ack pathway reported herein would be helpful to understand the energy acquisition inP. gingivalis.