dc.description.abstract | I t has been long known that bites from monitor lizards (Sauria: Varanidae) may cause severe infections and eventually lead to lethal bacteremia. I t is generally assumed that these infections are caused by microbial organisms living in the mouth cavity of monitors. Studying microbial diversity of the mouth cavity from samples taken from Indonesian monitor species, we obtained 12 Escherichia coli isolates, which showed resistance to ampicilin. Genetic diversity analysis employing pulsed field gel electrophoresis (PFGE) of 9 isolates revealed 7 different SpeI schizotypes. The other three isolates produced smear, degraded DNA banding pattern, possibly caused by endonuclease activity. UPGMA analysis of the Spet-schizotypes obtained from the E. coli isolates revealed ihree clusters. Two of the clusters contained isolates from the species V. salvator and V. yuwonoi, respectively. The third cluster comprised V. caerulivirens and V. salvator. Whereas the first two clusters showed a clear reference to species and localities, the third cluster may have been a result of cross-contamination from the cages where the speeimens were kept or the food administered. Physiological assays employing Microbaet" 24E(12E112A+12B) and DNA profiling analysis indicated that each of the E. coli isolates constitutes a normal element of the microbiota occurring in the mouths of the monitor species studied. Key words: ampicilin resistance, Escherichia coli, schizotyping, Varanus spp. | id |