Ulbrich N, Kumagai I, Erdmann V A
Nucleic Acids Res. 1984 Feb 24;12(4):2055-60. doi: 10.1093/nar/12.4.2055.
We have examined the number of rRNA genes in Thermus thermophilus HB8 by hybridization of Bam HI -, Hind III - and Pst I - digests of DNA to 3'- (3 2p) 23S, 16S and 5S rRNAs according to the Southern procedure. The restriction gels gave two radioactive bands with 23S and 5S rRNA. Furthermore, band positions were indistinguishable from one another when 23S and 5S rRNAs were used as probes to Bam HI and Hind III digests, indicating that each band contains sequences corresponding to the 3'-end of 23S and 5S rRNAs. The Pst I digest also gave two radioactive bands with 23S and 5S rRNAs as probes, where one band position was identical, but the other different. The 16S rRNA did hybridize with two fragments, using a Bam HI, as well as a Bam HI - Hind III double digest. The Hind III digest gave one band using 16S rRNA as a probe. It is concluded that the Thermus thermophilus HB8 chromosome carries at least two sets of genes for 23S, 16S and 5S rRNAs.
我们按照Southern印迹法,通过将嗜热栖热菌HB8的DNA经Bam HI、Hind III和Pst I酶切后的片段与3'-(32P)标记的23S、16S和5S rRNA进行杂交,检测了嗜热栖热菌HB8中rRNA基因的数量。限制性酶切凝胶用23S和5S rRNA探针检测时出现了两条放射性条带。此外,当用23S和5S rRNA作为Bam HI和Hind III酶切片段的探针时,条带位置无法区分,这表明每条带都包含与23S和5S rRNA 3'-末端相对应的序列。用23S和5S rRNA作为探针时,Pst I酶切片段也出现了两条放射性条带,其中一条带位置相同,但另一条不同。用16S rRNA作为探针时,Bam HI酶切片段以及Bam HI - Hind III双酶切片段均与两个片段杂交。用16S rRNA作为探针时,Hind III酶切片段出现了一条带。由此得出结论,嗜热栖热菌HB8染色体至少携带两组23S、16S和5S rRNA基因。