First isolation of Bdellovibrio sp. from Water and Soil samples in Rafsanjan city

Bdellovibrio bacteriovorus is an obligate predator of other Gram-negative bacteria. It grows in the periplasm of the prey cell and finally lyses them, so it has high potentials to be used in biocontrol of plant pathogenic bacteria. The objective of the present study was to isolate and characterize Bdellovibrios bacteria from soil and water samples of Rafsanjan (Kerman province) in Iran. To do this, after sampling, two Bdellovibrios isolates (Sar and Pj) were isolated by using Escherichia coli strain K12 as prey on the two layers agar. The isolates were identified by phenotypic and 16S rDNA PCR amplification and sequencing. The sequencing and phylogenetic studies showed that the strains have more than 99% similarity to B. bacteriovorus. Then, the host range and specificity of the strain were evaluated on 9 different Gram negative bacterial species. The results showed that the strains have predatory effects only on E. coli as prey.