The Borrelia burgdorferi circular plasmid cp26: conservation of plasmid structure and targeted inactivation of the ospC gene.
The Borrelia burgdorferi circular plasmid cp26: conservation of plasmid structure and targeted inactivation of the ospC gene.
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伯氏疏螺旋体环状质粒 cp26：质粒结构的保守和 ospC 基因的靶向失活。
DOI：
10.1046/j.1365-2958.1997.4711838.x
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发表时间：
1997
影响因子：
3.6
通讯作者：
Rosa,P
中科院分区：
文献类型：
--
作者：
Tilly,K;Casjens,S;Stevenson,B;Bono,JL;Samuels,DS;Hogan,D;Rosa,P
The 26 to 28 kb circular plasmid ofB. burgdorferi sensu lato(cp26) is ubiquitous among bacteria of this group and contains loci implicated in the mouse–tick transmission cycle. Restriction mapping and Southern hybridization indicated that the structure of cp26 is conserved among isolates from different origins and culture passage histories. The cp26ospCgene encodes an outer surface protein whose synthesis within infected ticks increases when the ticks feed, and whose synthesis in culture increases after a temperature upshift. Previous studies ofospCcoding sequences showed them to have stretches of sequence apparently derived from theospCgenes of distantly related isolates by homologous recombination after DNA transfer. We found conservation of the promoter regions of theospCandguaAgenes, which are divergently transcribed. We also demonstrated that the increase in OspC protein after a temperature upshift parallels increases in mRNA levels, as expected if regulatory regions adjoin the conserved sequences in the promoter regions. Finally, we used directed insertion to inactivate theospCgene of a non‐infectious isolate. This first example of directed gene inactivation inB. burgdorferishows that the OspC protein is not required for stable maintenance of cp26 or growth in culture.
