Agrobacterium Tumefaciens - Introduction and Working
Agrobacterium tumefaciens
Agrobacterium tumefaciens (updated scientific name: Rhizobium radiobacter) is a gram-negative rod-shaped bacteria closely related to nitrogen-fixing bacteria which dwell at root nodules in legumes and unlike most other soil-dwelling bacteria, it infects the roots of plants to cause Crown Gall Disease of the family Rhizobiaceae, which includes the nitrogen fixing legume symbionts. Unlike the nitrogen fixing symbionts, tumor producing Agrobacterium are pathogenic and do not benefit the plant. The wide variety of plants affected by Agrobacterium makes it of great concern to the agriculture industry. Various remediation methods, including utilization of a strain of closely related bacteria controls and limits its damage, but it is also useful as a genetic engineering tool in plants. It is famous for taking advantage of its host by injecting DNA derived from its Ti (tumor inducing) plasmid into its host, causing the plant to create galls which excrete opines that the bacteria use as an energy source. A. tumefaciens have emerged as an important molecular tool for manipulating plants and creating genetically modified crops for research and agriculture.
Genome structure
A. tumefaciens is one of the few bacterium that has both a linear and a circular chromosome. Its genome has a total of 5.7 million base-pairs, with 2.8 million residing on its circular chromosome and 2.1 million residing on its linear chromosome and although most of the genes essential for its survival are located on the circular chromosome; through evolution some essential genes have migrated to the linear chromosome. Based on sequence analysis, it was determined that the linear chromosome was derived from a plasmid that was transformed into the bacteria.
The ends of the linear chromosomes are protected by a telomere that forms a covalently closed hairpin, like in other bacteria which contain a linear chromosome. In addition to the two chromosomes, strain C58 also
Agrobacterium tumefaciens (updated scientific name: Rhizobium radiobacter) is a gram-negative rod-shaped bacteria closely related to nitrogen-fixing bacteria which dwell at root nodules in legumes and unlike most other soil-dwelling bacteria, it infects the roots of plants to cause Crown Gall Disease of the family Rhizobiaceae, which includes the nitrogen fixing legume symbionts. Unlike the nitrogen fixing symbionts, tumor producing Agrobacterium are pathogenic and do not benefit the plant. The wide variety of plants affected by Agrobacterium makes it of great concern to the agriculture industry. Various remediation methods, including utilization of a strain of closely related bacteria controls and limits its damage, but it is also useful as a genetic engineering tool in plants. It is famous for taking advantage of its host by injecting DNA derived from its Ti (tumor inducing) plasmid into its host, causing the plant to create galls which excrete opines that the bacteria use as an energy source. A. tumefaciens have emerged as an important molecular tool for manipulating plants and creating genetically modified crops for research and agriculture.
Genome structure
A. tumefaciens is one of the few bacterium that has both a linear and a circular chromosome. Its genome has a total of 5.7 million base-pairs, with 2.8 million residing on its circular chromosome and 2.1 million residing on its linear chromosome and although most of the genes essential for its survival are located on the circular chromosome; through evolution some essential genes have migrated to the linear chromosome. Based on sequence analysis, it was determined that the linear chromosome was derived from a plasmid that was transformed into the bacteria.
The ends of the linear chromosomes are protected by a telomere that forms a covalently closed hairpin, like in other bacteria which contain a linear chromosome. In addition to the two chromosomes, strain C58 also