Structural variation in the 16S-23S rRNA intergenic spacers of Vibrio parahaemolyticus

The 16S-23S rRNA intergenic spacers (IGS) of Vibrio parahaemolyticus were P CR-amplified and cloned with pT7Blue T vector. A total of six clones were i solated dependent on size difference. The clones were different with respec t to both the number and the composition of the tRNA genes included, and we re designated IGS-0, IGS-E, IGS-IA, IGS-AE, IGS-EKV and IGS-EKAV. IGS-EKAV included the cluster of tRNA(Glu)-tRNA(Lys)-tRNA(Ala)-tRNA(Val); IGS-EKV, t RNA(Glu)-tRNA(Lys)-tRNA(Val); IGS-AE, tRNA(Ala)-tRNA(Glu); IGS-IA, tRNA(Ile )- tRNA(Ala); and IGS-E, tRNA(Glu). IGS-0 had no tRNA gene. Some similariti es were found in the nucleotide sequence of the non-coding regions flanked by the tRNA genes. The structure difference found in the spacers is meaning ful for elucidating the evolutionary line of each ribosomal RNA operon and the profile is applicable as a molecular marker of the bacterium. (C) 2000 Federation of European Microbiological Societies. Published by Elsevier Sci ence B.V. All rights reserved.