A FAMILY OF IS1031 ELEMENTS IN THE GENOME OF ACETOBACTER-XYLINUM - NUCLEOTIDE-SEQUENCES AND STRAIN DISTRIBUTION

An insertion sequence (here called IS1031A) from Acetobacter xylinum A TCC 23769 has recently been isolated. This study describes the complet e nucleotide sequence of IS1031A as well as the sequences of two novel iso-IS1031 elements, IS1031C and IS1031D, from A. xylinum ATCC 23769. The three ISs are all exactly 930 bp long, have imperfect terminal in verted repeats of 24 bp for IS1031A and 21 bp for IS1031C and IS1031D, are flanked by three base pair direct repeats, and contain an open re ading frame encoding a putative basic protein of 278 amino acids. Beca use of nucleotide substitutions, IS1031C and IS1031D differ from IS103 1A by 12.9% while IS1031C differs from IS1031D by only 0.6%. Hybridiza tion analyses of total DNA from nine A. xylinum strains showed that al l strains contained IS1031-like elements varying in copy number from t hree to at least 16. None of three Acetobacter aceti strains examined contained IS1031-like elements. Taken together, the results suggest th at A. xylinum contains a family of IS1031 elements with considerably d iversified nucleotide sequences.