Genetic Engineering of Single-Domain Magnetic Bacteria.
Abstract
In this investigation, we have demonstrated that DNA from A. magnetotacticum can be functionally expressed in E. coli. However, for the same amino acids, the codons used by this bacterium are often different from those used by E. coli. The mechanism of iron-uptake in A. magnetotacticum is not mediated by a siderophore compound. However, the common pathway leading to the synthesis of aromatic amino acids and enterochelin, the E. coli siderophore, is conserved. We have isolated a mutant strain that is no longer magnetotactic. A major cytoplasmic protein present in the magnetotactic strain is absent in the mutant strain. We have purified and partially characterized this protein. We have cloned a fragment from DNA of A. magnetotacticum that allows growth in the presence of 2,2'-dipyridyl. Cells remove the chelator from the medium and gradually turn pink in color (dipyridyl + Fe2+ is pink). We have been able to grow A. magnetotacticum on solid medium under aerobic conditions by adding OxyraseTM -to the medium. Aquaspirillum magnetotacticum, magnetic bacteria, iron-uptake, siderophore.
Document Details
- Document Type
- Technical Report
- Publication Date
- Sep 25, 1992
- Accession Number
- ADA256186
Entities
People
- Nahid S. Walsh
Organizations
- SRI International