Hinnebusch B J, Bendich A J
Laboratory of Microbial Structure and Function, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, Montana 59840, USA.
J Bacteriol. 1997 Apr;179(7):2228-37. doi: 10.1128/jb.179.7.2228-2237.1997.
The nucleoids of Escherichia coli and the spirochetes Borrelia burgdorferi and Borrelia hermsii, agents of Lyme disease and relapsing fever, were examined by epifluorescence microscopy of bacterial cells embedded in agarose and lysed in situ with detergent and protease. The typical E. coli nucleoid was a rosette in which 20 to 50 long loops of DNA emanated from a dense node of DNA. The percentages of cells in a population having nucleoids with zero, one, two, and three nodes varied with growth rate and growth phase. The borrelia nucleoid, in contrast, was a loose network of DNA strands devoid of nodes. This nucleoid structure difference correlates with the unusual genome of Borrelia species, which consists primarily of linear replicons, including a 950-kb linear chromosome and linear plasmids. This method provides a simple, direct means to analyze the structure of the bacterial nucleoid.
通过对包埋在琼脂糖中并用去污剂和蛋白酶原位裂解的细菌细胞进行落射荧光显微镜检查，研究了大肠杆菌以及莱姆病和回归热病原体——疏螺旋体伯氏疏螺旋体和赫氏疏螺旋体的类核。典型的大肠杆菌类核呈玫瑰花结状，其中20至50个长的DNA环从密集的DNA节点发出。群体中具有零个、一个、两个和三个节点类核的细胞百分比随生长速率和生长阶段而变化。相比之下，疏螺旋体类核是一个没有节点的松散DNA链网络。这种类核结构差异与疏螺旋体属异常的基因组相关，该基因组主要由线性复制子组成，包括一条950kb的线性染色体和线性质粒。该方法提供了一种简单、直接的手段来分析细菌类核的结构。
