Structural and functional characterization of the LldR from Corynebacterium glutamicum: a transcriptional repressor involved in L-lactate and sugar utilization.
Structural and functional characterization of the LldR from Corynebacterium glutamicum: a transcriptional repressor involved in L-lactate and sugar utilization.
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DOI：
10.1093/nar/gkn827
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发表时间：
2008-12
影响因子：
14.9
通讯作者：
Yao M
中科院分区：
文献类型：
--
作者：
Gao YG;Suzuki H;Itou H;Zhou Y;Tanaka Y;Wachi M;Watanabe N;Tanaka I;Yao M
来自谷氨酸棒杆菌的LldR（CGL 2915）是属于GntR家族的转录因子，其通常参与调节与氨基酸代谢相关的氧化底物。在本研究中，LldR的晶体结构确定在2.05-nm分辨率。该结构由类似于FadR的N-和C-结构域组成，但具有不同的结构域取向。LldR和FadR二聚体通过结构域交换实现相似的结构，这首先在转录因子的二聚体组装中观察到。作为与FadR亚家族的差异，还观察到Zn 2+结合在调节结构域中的结构特征。DNA微阵列和DNA酶I足迹分析表明，LldR作为一个阻遏物调节cgl 2917-lldD和cgl 1934-fruK-ptsF操纵子，这是必不可少的l-乳酸和果糖/蔗糖利用，分别。此外，LldR和DNA的化学计量和亲和力通过等温滴定量热法测量确定。通过引物延伸测定分析转录起始位点和cgl 2917-lldD操纵子上LldR的阻遏。突变实验表明，残基Lys 4，Arg 32，Arg 42和Gly 63对DNA结合至关重要。提出了LldR与DNA结合空腔的位置及LldR对DNA亲和力的调控机制。
LldR (CGL2915) from Corynebacterium glutamicum is a transcription factor belonging to the GntR family, which is typically involved in the regulation of oxidized substrates associated with amino acid metabolism. In the present study, the crystal structure of LldR was determined at 2.05-Å resolution. The structure consists of N- and C-domains similar to those of FadR, but with distinct domain orientations. LldR and FadR dimers achieve similar structures by domain swapping, which was first observed in dimeric assembly of transcription factors. A structural feature of Zn2+ binding in the regulatory domain was also observed, as a difference from the FadR subfamily. DNA microarray and DNase I footprint analyses suggested that LldR acts as a repressor regulating cgl2917-lldD and cgl1934-fruK-ptsF operons, which are indispensable for l-lactate and fructose/sucrose utilization, respectively. Furthermore, the stoichiometries and affinities of LldR and DNAs were determined by isothermal titration calorimetry measurements. The transcriptional start site and repression of LldR on the cgl2917-lldD operon were analysed by primer extension assay. Mutation experiments showed that residues Lys4, Arg32, Arg42 and Gly63 are crucial for DNA binding. The location of the putative ligand binding cavity and the regulatory mechanism of LldR on its affinity for DNA were proposed.
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影响因子：
3.2
作者：
Georgi, Tobias;Engels, Verena;Wendisch, Volker F.
通讯作者：
Wendisch, Volker F.
DOI：
10.1073/pnas.85.6.1888
发表时间：
1988-03-01
影响因子：
11.1
作者：
IUCHI, S;LIN, ECC
通讯作者：
LIN, ECC
影响因子：
14.9
作者：
Holm, L;Sander, C
通讯作者：
Sander, C
影响因子：
4.1
作者：
Hermann, T
通讯作者：
Hermann, T
DOI：
10.1107/s0907444998003254
发表时间：
1998-09-01
期刊：
ACTA CRYSTALLOGRAPHICA SECTION D-BIOLOGICAL CRYSTALLOGRAPHY
影响因子：
--
作者：
Brunger, AT;Adams, PD;Warren, GL
通讯作者：
Warren, GL