Variation of the natural transformation frequency of Campylobacter jejuni in liquid shake culture.
Variation of the natural transformation frequency of Campylobacter jejuni in liquid shake culture.
复制标题
液体摇瓶培养中空肠弯曲杆菌自然转化频率的变化。
DOI：
10.1099/mic.0.26531-0
复制
发表时间：
2003
期刊：
影响因子：
--
通讯作者：
Linz,JohnE
中科院分区：
文献类型：
--
作者：
Wilson,DavidL;Bell,JuliaA;Young,VincentB;Wilder,StaceyR;Mansfield,LindaS;Linz,JohnE
Natural transformation, a mechanism that generates genetic diversity inCampylobacter jejuni, was studied in a novel liquid shake culturing system that allowed an approximately 10 000-fold increase in cell density.C. jejunitransformation frequency was analysed in this system under 10 %, 5·0 % and 0·7 % CO2atmospheres. At 5·0 % and 10 % CO2concentrations, when purified isogenic chromosomal DNA was used to assess competence, transformation frequency ranged from 10−3to 10−4at low cell concentrations and declined as cell density increased. Transformation frequency under a 0·7 % CO2atmosphere was more stable, maintaining 10−3levels at high cell densities, and was 10- to 100-fold higher than that under a 10 % CO2atmosphere. Three of fourC. jejunistrains tested under a 5·0 % CO2atmosphere were naturally competent for isogenic DNA; competent strains demonstrated a lack of barriers to intraspecies genetic exchange by taking up and incorporating chromosomal DNA from multipleC. jejunidonors.C. jejunishowed a preference for its own DNA at the species level, and co-cultivation demonstrated that DNA transfer via natural transformation occurred between isogenic populations during short periods of exposure in liquid medium when cell density and presumably DNA concentrations were low. Transformation frequency during co-cultivation of isogenic populations was also influenced by CO2concentration. Under a 0·7 % CO2atmosphere, co-cultivation transformation frequency increased approximately 500-fold in a linear fashion with regard to cell density, and was 1000- to 10 000-fold higher during late-exponential-phase growth when compared to cultures grown under a 10 % CO2atmosphere.
