A set of positively regulated flagellar gene promoters in Caulobacter crescentus with sequence homology to the nif gene promoters of Klebsiella pneumoniae.
A set of positively regulated flagellar gene promoters in Caulobacter crescentus with sequence homology to the nif gene promoters of Klebsiella pneumoniae.
复制标题
新月柄杆菌中一组正向调节的鞭毛基因启动子，与肺炎克雷伯菌的 nif 基因启动子具有序列同源性。
DOI：
10.1016/0022-2836(87)90497-9
复制
发表时间：
1987
影响因子：
5.6
通讯作者：
Newton,A
中科院分区：
文献类型：
--
作者：
Mullin,D;Minnich,S;Chen,LS;Newton,A
本文报道了新月柄杆菌Hook基因簇转录单元I和III的体内转录起始位点的核酸酶S1定位。我们发现，转录单位I和II的鞭毛（弗拉）基因簇，其中有不同的启动子与转录起始位点分开218个核苷酸，是在转录单位III的基因正转录控制。将转录单位I、II和III的启动子与最近在C. crescentus。受转录单位III至V正调控的启动子PII、P25和P27在−13和−24处具有高度保守的序列元件，共有序列为（C/T）TGGC（C/G）C-N5-TTGC。启动子PI中的-13、-24序列元件并不很保守，但启动子确实包含上游23个碱基对（PI *）的-13和-24共有序列的拷贝。C.新月体鞭毛基因启动子与大肠杆菌的−10，−35启动子序列不同源，但与肺炎克雷伯氏菌和根瘤菌的−12，− 24 nif基因启动子序列非常相似。在此研究的四个正调控的鞭毛基因启动子还共享第三个保守元件，命名为II-1，共有序列C-C-CGGC--AAA--GC-G，位于大约-100。我们推测，保守的序列元件映射在-13，-24和-100 arecis-acting调控元件所需的转录和周期性调控的这些鞭毛在C。新月形细胞周期
The study reported here describes nuclease S1mapping of thein-vivotranscription start sites of transcription units I and III of the hook gene cluster ofCaulobacter crescentus. We show that transcription units I and II of this flagellar (fla) gene cluster, which have divergent promoters with transcription start sites separated by 218 nucleotides, are under positive transcriptional control by genes in transcription unit III. The promoters of transcription units I, II, and III were compared with flagellin gene promoters P25, P27 and P29 recently identified inC. crescentus. Promoters PII, P25, and P27, which are under positive regulation by transcription units III to V have strongly conserved sequence elements at −13 and −24 with the consensus sequence (C/T)TGGC(C/G)C-N5-TTGC. The −13, −24 sequence elements are not well conserved in promoter PI, but the promoter does contain a copy of the −13 and −24 consensus sequence 23 base-pairs upstream (PI∗). TheC. crescentus flagene promoters are not homologous to the canonicalEscherichia coli−10, −35 promoter sequence, but they are very similar to the −12, −24nifgene promoter sequence reported forKlebsiella pneumoniaeandRhizobiumsp. The four positively regulatedflagene promoters examined here also share a third conserved element designated II-1, with the consensus sequence C-C-CGGC--AAA--GC-G, located at approximately −100. We speculate that the conserved sequence elements mapping at −13, −24 and −100 arecis-acting regulatory elements required for the transcription and periodic regulation of theseflagenes in theC. crescentuscell cycle.