To reveal the intraspecific evolution of Leptospirillum ferriphilum isolates which thrived in industrial bioleaching ecosystems and acid mine drainages,genome sequences of L.ferriphilum YSK,L.ferriphilum DX and L.ferr...To reveal the intraspecific evolution of Leptospirillum ferriphilum isolates which thrived in industrial bioleaching ecosystems and acid mine drainages,genome sequences of L.ferriphilum YSK,L.ferriphilum DX and L.ferriphilum ZJ were determined to compare with complete genome of L.ferriphilum ML-04.The genome comparisons reveal that extensive intraspecific variation occurs in their genomes,and that the loss and insertion of novel gene blocks of probable phage origin may mostly contribute to heterogeneity of gene content among L.ferriphilum genomes.Surprisingly,a nif gene cluster is identified in L.ferriphilum YSK and L.ferriphilum ZJ genomes.Intensive analysis and further experiments indicate that the nif gene cluster in L.ferriphilum YSK inherits from ancestor rather than lateral gene transfer.Overall,results suggest that the population of L.ferriphilum undergoes frequent genetic recombination,resulting in many closely related genome types in recent evolution.The combinatorial processes profoundly shape their physiologies and provide the basis for adaptation to different niches.展开更多
基金Project(2018YFC1801804)supported by the National Key R&D Program of ChinaProjects(2016JJ3146,2017JJ3160)supported by the Natural Science Foundation of Hunan Province,China。
文摘To reveal the intraspecific evolution of Leptospirillum ferriphilum isolates which thrived in industrial bioleaching ecosystems and acid mine drainages,genome sequences of L.ferriphilum YSK,L.ferriphilum DX and L.ferriphilum ZJ were determined to compare with complete genome of L.ferriphilum ML-04.The genome comparisons reveal that extensive intraspecific variation occurs in their genomes,and that the loss and insertion of novel gene blocks of probable phage origin may mostly contribute to heterogeneity of gene content among L.ferriphilum genomes.Surprisingly,a nif gene cluster is identified in L.ferriphilum YSK and L.ferriphilum ZJ genomes.Intensive analysis and further experiments indicate that the nif gene cluster in L.ferriphilum YSK inherits from ancestor rather than lateral gene transfer.Overall,results suggest that the population of L.ferriphilum undergoes frequent genetic recombination,resulting in many closely related genome types in recent evolution.The combinatorial processes profoundly shape their physiologies and provide the basis for adaptation to different niches.
文摘目的观察咬合分析仪在正畸治疗末期的临床效果。方法选择20例正畸治疗进入精细调整末期的患者,使用咬合分析系统记录正畸患者进入精细调整末期时刻(T1)全牙列总合力值(total occlusion force,TOF)、全牙列总接触面积(total contact area,TCA)、合不对称指数(asymmetry index of occlusal force,AOF)、左右两侧总合力值(left/right occlusion force,LOF/ROF)、合力中心轨迹(centre of force,COF)的位置,根据T1期结果,指导临床3个月的精细调整,记录正畸患者矫治结束时刻(T2)TOF、TCA、TOL、TOR及COF的位置,并将两组数据进行分析比较。结果 T_2期TCA、TOF、TOL、TOR均高于T1期,AOF小于T1期,差异有统计学意义(P均<0.05);T2期COF的位置优于T1期,差异有统计学意义(P<0.05);ROF在T_2期与T_1期的差值小于LOF,差异有统计学意义(P<0.05)。结论咬合分析仪应用于正畸治疗末期有助于指导临床正畸医生精细调整,达到合平衡,提高正畸疗效,建立长期而稳定的咬合关系。
