Monstein H J, Jonasson J
Molecular Biology Laboratory-LMO, Clinical Microbiology, Faculty of Health Sciences, S-581 85 Linköping, Sweden.
Biochem Biophys Res Commun. 2001 Jul 13;285(2):530-6. doi: 10.1006/bbrc.2001.5179.
Controversy exists whether coccoid forms of Helicobacter pylori maintain transcriptional and translational processes. The aim of the present study was to investigate mRNA levels in coccoid H. pylori and, if possible, to establish a correlation with the state of nonrandom fragmentation of rRNA in those cells. For that purpose, UreA, UreI, CagA, VacA, SodB, and Hsp60 mRNA levels in bacillary and coccoid forms of H. pylori CCUG 17874(T), H. pylori 26695, and H. pylori J99, respectively, were studied by means of a multiplex reverse-transcription PCR assay and Southern blot analysis of the RT-PCR-amplified products. Nonrandom fragmentation of 23S rRNA was assessed by a recently described assay. Virulence-gene-derived mRNA transcripts were visualized in DNase I-treated RNA preparations. All three strains revealed the presence of different mRNA patterns in bacillary and coccoid forms. Putative promoter sequences similar to the consensus Escherichia coli -10 hexamer TATAAA box were present in all six virulence genes analyzed. Moreover, the decrease seen in mRNA levels during conversion into the coccoid form appeared to correlate with the 23S rRNA nonrandom fragmentation pattern. The present data indicate that modulation of virulence-gene expression is differently regulated in bacillary and coccoid H. pylori.
幽门螺杆菌的球形形式是否维持转录和翻译过程存在争议。本研究的目的是调查球形幽门螺杆菌中的mRNA水平，并在可能的情况下，建立这些细胞中rRNA非随机片段化状态与mRNA水平的相关性。为此，分别通过多重逆转录PCR分析和RT-PCR扩增产物的Southern印迹分析，研究了幽门螺杆菌CCUG 17874(T)、幽门螺杆菌26695和幽门螺杆菌J99的杆菌形式和球形形式中UreA、UreI、CagA、VacA、SodB和Hsp60的mRNA水平。通过最近描述的分析方法评估23S rRNA的非随机片段化。在经DNase I处理的RNA制剂中观察到毒力基因衍生的mRNA转录本。所有三株菌株在杆菌形式和球形形式中均显示出不同的mRNA模式。在所分析的所有六个毒力基因中均存在与大肠杆菌共有-10六聚体TATAAA框相似的推定启动子序列。此外，转化为球形形式过程中mRNA水平的下降似乎与23S rRNA非随机片段化模式相关。目前的数据表明毒力基因表达的调节在幽门螺杆菌的杆菌形式和球形形式中受到不同的调控。
