Stability of plasmid pA387 derivatives in Amycolatopsis mediterranei producing rifamycin.
Genetic studies on the biosynthesis of rifamycins in producer strains such as Amylcolaptopsis mediterranei U-32 are severely hampered by the availability of efficient transformation procedures and stable plasmid vectors. Using an efficient electroporation procedure we have studied the replication and stability of a pA387 derivative, pDXM32. This plasmid confers enhanced plasmid stability and copy number compared to pA387 derivatives commonly used as cloning vectors in A. mediterranei. Deletion derivatives in the region previously identified as being a minimal replication origin were also examined with respect to their ability to transform A. mediterranei and at least one locus was essential for replication. A 5.4 kbp DNA fragment was sequenced and annotated encoding the replication and plasmid stability functions. A parA homologue was identified which is likely to confer plasmid stability.
Laboratory of Molecular Microbiology, Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, 300 Fenglin Road, Shanghai 200032, PR China.
Xiaoming
X
Ding
Yongqiang
Y
Tian
Juishen
J
Chiao
Guoping
G
Zhao
Weihong
W
Jiang
D000191:Actinomycetaceae / Q000145:classification / Q000235:genetics* / Q000378:metabolism*; D000595:Amino Acid Sequence; D001426:Bacterial Proteins / Q000235:genetics* / Q000378:metabolism*; D018274:Electroporation / Q000379:methods*; D018628:Gene Dosage; D015964:Gene Expression Regulation, Bacterial / Q000235:genetics*; D018014:Gene Transfer Techniques; D005818:Genetic Engineering / Q000379:methods; D005822:Genetic Vectors; D042822:Genomic Instability / Q000235:genetics; D008969:Molecular Sequence Data; D010957:Plasmids / Q000235:genetics*; D012294:Rifamycins / Q000096:biosynthesis*; D020539:Sequence Analysis, Protein; D017385:Sequence Homology
D001426:Bacterial Proteins; D012294:Rifamycins; C052883:chromosome partition proteins, bacterial