Fu Yajuan, Zepeda-Gurrola Reyna Cristina, Aguilar-Gutiérrez Germán Rubén, Lara-Ramírez Edgar E, De Luna-Santillana Erick J, Rodríguez-Luna Isabel Cristina, Sánchez-Varela Alejandro, Carreño-López Ricardo, Moreno-Medina Víctor Ricardo, Rodríguez-Pérez Mario A, López-Vidal Yolanda, Guo Xianwu
Centro de Biotecnología Genómica, Instituto Politécnico Nacional, Boulevard del Maestro S/N esq. Elías Piña, Col. Narciso Mendoza, Cd., 88710, Reynosa, Tamaulipas, Mexico.
Curr Microbiol. 2014 Feb;68(2):211-9. doi: 10.1007/s00284-013-0466-7. Epub 2013 Oct 6.
Helicobacter pylori infects more than half of the world's population, making it the most widespread infection of bacteria. It has high genetic diversity and has been considered as one of the most variable bacterial species. In the present study, a PCR-based method was used to detect the presence and the relative frequency of homologous recombination between repeat sequences (>500 bp) in H. pylori 26695. All the recombinant structures have been confirmed by sequencing. The inversion generated between inverted repeats showed distinct features from the recombination for duplication or deletion between direct repeats. Meanwhile, we gave the mathematic reasoning of a general formula for the calculation of relative recombination frequency and indicated the conditions for its application. This formula could be extensively applied to detect the frequency of homologous recombination, site-specific recombination, and other types of predictable recombination. Our results should be helpful for better understanding the genome evolution and adaptation of bacteria.
幽门螺杆菌感染了全球半数以上人口，是分布最为广泛的细菌感染源。它具有高度的遗传多样性，被认为是变异最大的细菌物种之一。在本研究中，我们采用基于聚合酶链式反应（PCR）的方法来检测幽门螺杆菌26695中重复序列（>500bp）之间同源重组的存在及相对频率。所有重组结构均通过测序得以确认。反向重复序列间产生的倒位与正向重复序列间的重复或缺失重组表现出明显不同的特征。同时，我们给出了计算相对重组频率通用公式的数学推导，并指出了其应用条件。该公式可广泛应用于检测同源重组、位点特异性重组及其他可预测重组类型的频率。我们的研究结果有助于更好地理解细菌的基因组进化与适应性。
