TherecAgene is crucial to mediate colonization ofBacillus cereus905 on wheat roots
TherecAgene is crucial to mediate colonization ofBacillus cereus905 on wheat roots
复制标题
recA 基因对于介导蜡状芽孢杆菌 905 在小麦根部的定殖至关重要
DOI：
10.1007/s00253-020-10915-2
复制
发表时间：
2020-09-24
影响因子：
5
通讯作者：
Wang, Qi
中科院分区：
文献类型：
--
作者：
Gao, Tantan;Ding, Mingzheng;Wang, Qi
蜡状芽孢杆菌905是一种能在小麦根系大量定殖的植物根际促生细菌。从以往的研究中，我们了解到，sodA 2编码的含锰超氧化物歧化酶（MnSOD 2）对B. cereus 905在小麦根际中存活。在这项研究中，我们证明，删除therecA基因，编码重组酶A，显着降低MnSOD 2的表达在mRNA和蛋白质水平。通过与野生型相比，增量recA显示暴露于50 μ M百草枯或15 mM H2 O2后细胞存活率急剧下降。有证据表明，B. cereus 905还显著调节营养利用效率、生物膜形成和群集运动。根定殖试验表明，RecA的增加使根定殖率降低1000 ~ 2500倍，表明RecA在B菌有效定殖小麦根中起着不可或缺的作用。cereus905.综上所述，recA基因正调控MnSOD 2的产生和营养利用，并保护B. cereus 905细胞对百草枯和H2 O2的耐受性。此外，B. cereus 905由RecA促进。RecA基因在小麦根中的定殖作用显著。cereus905.结果表明RecA在B. cereus 905，特别是在小麦根上定殖。本研究结果为深入研究B. cereus 905的研究，为提高PGPR菌株的生防效果提供了潜在的有效策略。
Bacillus cereus905, one of the plant growth-promoting rhizobacteria (PGPRs), is capable of colonizing wheat roots in a large population size. From previous studies, we learned that thesodA2-encoding manganese-containing superoxide dismutase (MnSOD2) is important forB. cereus905 to survive in wheat rhizosphere. In this investigation, we demonstrated that deletion of therecAgene, which codes for the recombinase A, significantly reduced MnSOD2 expression at both the mRNA and the protein levels. Through comparison with the wild-type, the increment recAshowed a dramatic decrease in cell survival after exposure to 50 mu M paraquat or 15 mM H2O2. Evidence indicated that therecAgene ofB. cereus905 also notably regulated nutrition utilization efficiency, biofilm formation, and swarming motility. The root colonization examination showed that the increment recAhad a 1000- to 2500-fold reduction in colonization on wheat roots, suggesting that RecA plays an indispensable role in effective colonization on wheat roots byB. cereus905. Taken together, therecAgene positively regulates MnSOD2 production and nutrition utilization and protectsB. cereus905 cells against paraquat and H2O2. Besides, biofilm formation and swarming motility ofB. cereus905 are promoted by RecA. Finally, RecA significantly contributes to wheat root colonization ofB. cereus905. Our results showed the important role of RecA during physiological processes inB. cereus905, especially for colonization on wheat roots. Our findings will point out a research direction to study the colonization mechanisms ofB. cereus905 in the future and provide potential effective strategy to enhance the biocontrol efficacy of PGPR strains.