Construction of conjugative gene transfer system between E. coli and moderately thermophilic, extremely acidophilic Acidithiobacillus caldus MTH-04.
A genetic transfer system for introducing foreign genes to biomining microorganisms is urgently needed. Thus, a conjugative gene transfer system was investigated for a moderately thermophilic, extremely acidophilic biomining bacterium, Acidithiobacillus caldus MTH-04. The broad-host-range IncP plasmids RP4 and R68.45 were transferred directly into A. caldus MTH-04 from Escherichia coli by conjugation at relatively high frequencies. Additionally the broad-host-range IncQ plasmids pJRD215, pVLT33, and pVLT35 were also transferred into A. caldus MTH-04 with the help of plasmid RP4 or strains with plasmid RP4 integrated into their chromosome, such as E. coli SM10. The Km(r) and Sm(r) selectable markers from these plasmids were successfully expressed in A. caldus MTH-04. Futhermore, the IncP and IncQ plasmids were transferred back into E. coli cells from A. caldus MTH-04, thereby confirming the initial transfer of these plasmids from E. coli to A. caldus MTH-04. All the IncP and IncQ plasmids studied were stable in A. caldus MTH-04. Consequently, this development of a conjugational system for A. caldus MTH-04 will greatly facilitate its genetic study.
State Key Laboratory of Microbial Technology, Shandong University, Jinan 250100, PR China. liuxiangmei@sdu.edu.cn
Xiangmei
X
Liu
Jianqun
J
Lin
Zheng
Z
Zhang
Jiang
J
Bian
Qing
Q
Zhao
Ying
Y
Liu
Jianqiang
J
Lin
Wangming
W
Yan
D042763:Acidithiobacillus / Q000235:genetics* / Q000502:physiology; D003227:Conjugation, Genetic; D004926:Escherichia coli / Q000235:genetics*; D018014:Gene Transfer Techniques; D042822:Genomic Instability; D006358:Hot Temperature; D006863:Hydrogen-Ion Concentration; D010957:Plasmids / Q000235:genetics