Characterization of genetic determinants for R body synthesis and assembly in Caedibacter taeniospiralis 47 and 116
Characterization of genetic determinants for R body synthesis and assembly in Caedibacter taeniospiralis 47 and 116
复制标题
带状螺旋线杆菌 47 和 116 中 R 体合成和组装的遗传决定因素的表征
DOI：
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发表时间：
1994
影响因子：
3.2
通讯作者：
R. L. Quackenbush
中科院分区：
文献类型：
--
作者：
D. Heruth;F. R. Pond;J. Dilts;R. L. Quackenbush
带旋Caedibacter taeniospiralis是四脲草履虫（Paramecium tetraurelia）的一种专性内共生细菌，具有杀灭草履虫的特性。51型R体（嗜杀包涵体）由这些内共生体合成，并且是表达杀伤特性所需的。测定了C. taeniospiralis 47和116。三个独立转录的基因（rebA，rebB和rebC）进行了表征。到目前为止，这些基因是唯一来自C。带螺旋体进行测序和鉴定。DNA调控区被大肠杆菌识别，密码子使用与大肠杆菌相似。杆菌在reb基因座中发现了第四个开放阅读框，并有适当的调控序列，但没有证据表明该基因在大肠杆菌中表达。杆菌来自两种菌株的R体编码序列是相同的。缺失衍生物的二维凝胶电泳显示，两个聚合事件参与R体组装。一个聚合事件只需要RebB和RebC;另一个需要所有三种蛋白质。RebC的表达对于将RebA和RebB翻译后修饰为分别具有三种和两种不同分子量的物种是必要的。在RebC的存在下，具有不同分子量的每种RebB具有六个不同的等电点。
Caedibacter taeniospiralis, an obligate bacterial endosymbiont of Paramecium tetraurelia, confers a killing trait upon its host paramecium. Type 51 R bodies (refractile inclusion bodies) are synthesized by these endosymbionts and are required for expression of the killing trait. The nucleotide sequence of the genetic determinants for type 51 R body synthesis and assembly was determined for C. taeniospiralis 47 and 116. Three independently transcribed genes (rebA, rebB, and rebC) were characterized. To date these are the only genes from C. taeniospiralis to be sequenced and characterized. DNA regulatory regions are recognized by Escherichia coli, and codon usage appears similar to that in E. coli. A fourth open reading frame with appropriate regulatory sequences was found within the reb locus, but no evidence was obtained to suggest that this putative gene is expressed in E. coli. The R body-encoding sequences from both strains are identical. Two-dimensional gel electrophoresis of deletion derivatives shows that two polymerization events are involved in R body assembly. One polymerization event requires only RebB and RebC; the other requires all three proteins. Expression of RebC is necessary for the posttranslational modification of RebA and RebB into species with three and two different molecular weights, respectively. In the presence of RebC, each species of RebB with a different molecular weight has six different isoelectric points.
影响因子：
14.9
作者：
SHARP, PM;LI, WH
通讯作者：
LI, WH
草履虫及其染色体外元素的染色体外元素。
DOI：
10.1007/978-1-4684-5251-8_21
发表时间：
1986
期刊：
Basic life sciences
影响因子：
--
作者：
Quackenbush,RL;Cox,BJ;Kanabrocki,JA
通讯作者：
Kanabrocki,JA