Nif-hybrids of Enterobacter cloacae: Selection for nif-gene integration with nif-plasmids containing the Mu transposon

✍ Scribed by Nguyen, N. D. ;Göttfert, M. ;Singh, M. ;Klingmüller, W.

• Publisher: Springer
• Year: 1983
• Tongue: English
• Weight: 547 KB
• Volume: 192
• Category: Article
• ISSN: 0026-8925
• DOI: 10.1007/bf00392188

✦ Synopsis

The nitrogen fixation (n~-gene group of Klebsiella can be transferred onto Enterobacter cloacae by conjugation, using Escherichia coIi donor cells carrying the composite self-transmissible n/f-plasmid pRD1. To enforce integration and stabilisation, in the present study a derivative of pRD1, viz plasmid pCE1, containing the Mu transposon was used. pCE1 :: Mu cts makes Enterobacter cloacae cells n/f +, and sensitive to temperature induction of Mu. Few cells survive treatment at 42 ° C. Seventy-two isolates thus obtained were screened for location of their n/f-genes. At least four were found to contain the n/f-genes integrated into the chromosome. This was documented by gel electrophoresis of their DNA, and by Southern hybridisation of their DNA with Klebsiella n/f-KDH DNA as radioactive probe. The Mu transposon had also become part of their chromosome.