Two-component systems of Corynebacterium glutamicum:: Deletion analysis and involvement of the PhoS-PhoR system in the phosphate starvation response
Two-component systems of Corynebacterium glutamicum:: Deletion analysis and involvement of the PhoS-PhoR system in the phosphate starvation response
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DOI：
10.1128/jb.188.2.724-732.2006
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发表时间：
2006-01-01
影响因子：
3.2
通讯作者：
Bott, M
中科院分区：
文献类型：
--
作者：
Kocan, M;Schaffer, S;Bott, M
谷氨酸棒杆菌含有13个双组分信号转导系统的基因。为了测试它们在磷饥饿适应性反应中的重要性和参与，构建了一组12个缺失突变体。其中一个突变株在等电点限制下的生长能力明显受损，因此该菌株中缺乏的基因被命名为PHOS(编码传感器激酶)和phor(编码反应调节因子)。对C谷氨酸菌野生型和Delta PhoRS突变体的DNA微阵列分析支持PhoRS系统在适应磷饥饿中的作用。与野生型相比，Delta PhoRS突变体在从P过量转变为PI限制后1小时内没有诱导已知的PI饥饿诱导(Psi)基因，但pstSCAB操纵子仍被部分诱导。这表明PHOR具有激活功能，并且存在至少一个额外的PST操纵子调节子。对所选psi基因(pstS、ugpA、phor、UshA和Nuch)的引物延伸分析证实了微阵列数据，并为PhoRS基因的阳性自我调节提供了证据。
Corynebacterium glutamicum contains genes for 13 two-component signal transduction systems. In order to test for their essentiality and involvement in the adaptive response to phosphate (Pi) starvation, a set of 12 deletion mutants was constructed. One of the mutants was specifically impaired in its ability to grow under Pi limitation, and therefore the genes lacking in this strain were named phoS (encoding the sensor kinase) and phoR (encoding the response regulator). DNA microarray analyses with the C glutamicum wild type and the Delta phoRS mutant supported a role for the PhoRS system in the adaptation to P, starvation. In contrast to the wild type, the Delta phoRS mutant did not induce the known Pi starvation-inducible (psi) genes within 1 hour after a shift from P, excess to Pi limitation, except for the pstSCAB operon, which was still partially induced. This indicates an activator function for PhoR and the existence of at least one additional regulator of the pst operon. Primer extension analysis of selected psi genes (pstS, ugpA, phoR, ushA, and nucH) confirmed the microarray data and provided evidence for positive autoregulation of the phoRS genes.