概括
大肠杆菌染色体含有两种具有不同的组织的氨酸tRNA基因 (tRNA1Tyr和tRNA2Tyr). tRNA1Tyr基因与间隔器重复,而tRNA2Tyr是包括新型tRNA在内的更大集群的一部分.
科学领域:
- 分子生物学分子生物学
- 遗传学 遗传学 是一个
- 微生物学 微生物学
背景情况:
- 大肠杆菌的染色体含有对铁素受体tRNA (tRNA1Tyr和tRNA2Tyr) 的基因.
- 之前的研究使用专门的转导菌体分析了这些基因.
研究的目的:
- 确定大肠杆菌染色体上tRNA1Tyr和tRNA2Tyr基因集群的结构和组织.
- 将染色体组织与菌体分析的结果进行比较.
主要方法:
- 基因序列和组织的比较分析.
- 对大肠杆菌染色体DNA结构的检查.
- 对专门的转导菌体DNA进行分析.
主要成果:
- tRNA1Tyr基因 (tyrT) 由两个序列组成,由200bp的基因间隔隔隔隔,包括一个依赖于rho的转录终结位点.
- tRNA2Tyr基因 (tyrU) 是一个与其他tRNA基因集群的单个副本:tRNA4Thr--8 bp--tRNA2Tyr--115 bp--tRNA2Gly--6 bp--tRNA3Thr.
- tRNA2Tyr集群包括一个以前未被描述的tRNA,tRNA4Thr.
- 菌体分析部分反映了染色体组织,但发现了差异.
结论:
- 已经阐明了tRNA1Tyr和tRNA2Tyr基因集群在大肠杆菌染色体上的组织.
- 直接染色体分析对于准确的基因组织至关重要,因为菌体研究可能不能完全代表原生结构.
- 在tRNA2Tyr基因中发现了一种新型tRNA (tRNA4Thr).
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