[Construction of Frankia genomic libraries and isolation of clones homologous to nodulation genes from Rhizobium leguminosarum].
High molecular genomic DNAs were isolated by using the lysozyme plus achromopeptidase system from Frankia strains At4, Ccol and Hr16, the root nodule endophytes of Alnus, Casuarina and Hippophae respectively, and used to construct genomic libraries in pLAFR1, a broad host range cosmid vector within many gram-negative hosts. The genomic libraries were screened by in situ colony hybridization to identify clones homologous to common nodulation genes of Rhizobium leguminosarum, based on the sequence homology of EcoRI-digested Frankia total DNA to nodABC from Rhizobium meliloti. Several clones showing relatively strong hybridization were found, the recombinant plasmid was isolated, and their homology with Rhizobium nodulation genes was confirmed by spot hybridization. Further work on these positive clones is now underway.
Cui
Y H
YH
Laboratory of Molecular Genetics, Guangxi Agricultural College, Nanning.
Qin
M
M
Wang
Y L
YL
Ding
J
J
Ma
Q S
QS
D000192:Actinomycetales / Q000235:genetics*; D015723:Gene Library; D012231:Rhizobium / Q000235:genetics*; D012689:Sequence Homology, Nucleic Acid