An Open Reading Frame Downstream ofRhizobium meliloti nodQ1Shows Nucleotide Sequence Similarity to anAgrobacterium tumefaciensInsertion Sequence

We sequenced a small uncharacterized region in the Rhizobium meliloti nod gene cluster downstream of nodQ1. We found the beginning of a large open reading frame (260 amino acids) in this fragment. The sequence reported here has striking similarity to IS66 (Y. Machida, M. Sakurai, S. Kiyokawa, A. Ubasawa, and S. Yasushiro, 1984, Proc. Natl. Acad. Sci. USA 81:7495-7499), an insertion element found in an Agrobacterium tumefaciens mutant.