Abstrak 
Identification of New -lactamase Inhibitor Producing Microorganisms From Indonesiandonesia
Sri Agung Fitri Kusuma, Valentina Yurina
Unpad
Inggris
Unpad
ampicillin resistant Escherichia coli, beta-lactamase inhibitor, Indonesia
Despite of increasing numbers of Escherichia coli resistant to combination of ampicillin and clavulanic acid stated in recent reports, discovery of new -lactamase inhibitor becomes important. Our previous experiment showed that some microorganisms isolated from Indonesia have potency to produce inhibitor against clinical isolate -lactamase producing E. coli. Objectives of this research were to determine the dose dependent effect of extracellular products of ten ?-lactamase inhibitor producing bacteria from Indonesia and to identify the species of the producers. ?-lactamase inhibitor activity assay was conducted by agar diffusion method using clinical isolate E. coli producing -lactamase. Our results showed that extracellular product of nine bacteria under study had -lactamase inhibitor activity. These bacteria also have antibiotic activity against both resistant and sensitive E. coli strains. The dose-dependent effect assay of one extracellular product showed more potent antibiotic activity than betalactamase inhibiting activity. Bacterial identification with phenotypic approach was done by colony and cell morphology observation as well as biochemical assays; and with genotypic approach was done by 16S rDNA-based method. Species identification of nine beta-lactamase inhibitor producing bacteria were Streptomyces brasiliensis, Staphylococcus equorum, Salmonella typhi, Pseudomonas fluorescens, P. putida, Enterobacter hormaechei, Aeromonas popoffii, Enterobacter sp. and Serratia marcescens. While the species of antibiotic producer was Alcaligenes faecalis.