title: Cloning and expression of Trypanosoma brucei kinetoplast DNA in Escherichia coli.
abstract: The kinetoplast DNA of Trypanosoma brucei is made of two components: mini-circles (1 kb, 90% of total kDNA) and maxi-circles (20 kb, 10%) of total kDNA). These are interlocked to form a network of about 10 000 kb. In order to analyse the components of such a network structure, we have cloned individual mini-circle molecules and two of the three EcoRI maxi-circle fragments in E. coli. Cloned mini-circles are somewhat heterogeneous in size and their restriction patterns are completely different. Despite this heterogeneity all are found to contain a homologous region(s) defined by DNA/DNA hybridization. The maxi-circles probably correspond to the mitochondrial DNA of other organisms and, in contrast to mini-circles, do not show sequence heterogeneity. One of the two cloned maxi-circle EcoRI fragments is able to direct the synthesis of two polypeptides of 10 300 and 13 500 daltons in E. coli mini-cells. Detailed analysis of this phenomenon shows that both structural genes and promoter(s) are located within the cloned maxi-circle fragment.
mesh_terms: D000818:Animals; D003001:Cloning, Molecular; D004247:DNA / Q000235:genetics*; D004269:DNA, Bacterial / Q000235:genetics; D004274:DNA, Recombinant / Q000378:metabolism; D004926:Escherichia coli / Q000235:genetics; D005111:Extrachromosomal Inheritance; D005796:Genes; D008970:Molecular Weight; D009693:Nucleic Acid Hybridization; D009940:Organoids / Q000378:metabolism; D011506:Proteins / Q000032:analysis; D014346:Trypanosoma brucei brucei / Q000235:genetics*
chemical_list: D004269:DNA, Bacterial; D004274:DNA, Recombinant; D011506:Proteins; D004247:DNA