Beumer Amy, Robinson Jayne B
University of Dayton, 300 College Park, Dayton, OH 45469-1644, USA.
Appl Environ Microbiol. 2005 Dec;71(12):8301-4. doi: 10.1128/AEM.71.12.8301-8304.2005.
Genomic analysis has revealed heterogeneity among bacterial 16S rRNA gene sequences within a single species; yet the cause(s) remains uncertain. Generalized transducing bacteriophages have recently gained recognition for their abundance as well as their ability to affect lateral gene transfer and to harbor bacterial 16S rRNA gene sequences. Here, we demonstrate the ability of broad-host-range, generalized transducing phages to acquire 16S rRNA genes and gene sequences. Using PCR and primers specific to conserved regions of the 16S rRNA gene, we have found that generalized transducing phages (D3112, UT1, and SN-T), but not specialized transducing phages (D3), acquired entire bacterial 16S rRNA genes. Furthermore, we show that the broad-host-range, generalized transducing phage SN-T is capable of acquiring the 16S rRNA gene from two different genera: Sphaerotilus natans, the host from which SN-T was originally isolated, and Pseudomonas aeruginosa. In sequential infections, SN-T harbored only 16S rRNA gene sequences of the final host as determined by restriction fragment length polymorphism analysis. The frequency of 16S rRNA gene sequences in SN-T populations was determined to be 1 x 10(-9) transductants/PFU. Our findings further implicate transduction in the horizontal transfer of 16S rRNA genes between different species or genera of bacteria.
基因组分析揭示了单一物种内细菌16S rRNA基因序列的异质性；但其原因仍不确定。广义转导噬菌体最近因其数量众多以及影响侧向基因转移和携带细菌16S rRNA基因序列的能力而受到关注。在此，我们证明了广宿主范围的广义转导噬菌体获取16S rRNA基因和基因序列的能力。使用针对16S rRNA基因保守区域的PCR和引物，我们发现广义转导噬菌体（D3112、UT1和SN-T），而非特异性转导噬菌体（D3），获取了完整的细菌16S rRNA基因。此外，我们表明广宿主范围的广义转导噬菌体SN-T能够从两个不同属获取16S rRNA基因：最初分离出SN-T的宿主浮游球衣菌以及铜绿假单胞菌。在连续感染中，通过限制性片段长度多态性分析确定，SN-T仅携带最终宿主的16S rRNA基因序列。SN-T群体中16S rRNA基因序列的频率被确定为1×10(-9)转导子/噬菌斑形成单位。我们的发现进一步表明转导参与了不同物种或属细菌之间16S rRNA基因的水平转移。
