Deletions/insertions, short inverted repeats, sequences resembling att-lambda, and frame shift mutated open reading frames are involved in chloroplast DNA differences in the genus Oenothera subsection Munzia.

A restriction fragment length mutation has been mapped in the large single copy region of the chloroplast DNA from two Munzi-Oenothera species. Fragments containing the deletion/insertion were cloned, further analysed by additional restriction enzymes, and sequenced. A deleted/inserted 136 bp sequence was identified upstream of the 5' end of a tRNA-Leu (UAA) gene and presumably is located in the spacer between this gene and a tRNA-Thr (UGU) gene. The endpoints of the 136 bp sequence are covered by short inverted repeats. Complementary inverted repeats are present in the middle of the deleted/inserted sequence. The repeats are part of sequences resembling the lambda chromosomal attachment site (att-lambda) which is essential for site specific recombination in the lambda/Escherichia coli system. Possible interactions of the repeats during the deletion/insertion process are discussed. The spacer also contains a 1 bp deletion/insertion within an open reading frame (ORF). Due to this frame shift mutation the ORF sizes are quite different between the two Oenothera species.