Characterization and antibiotic sensitiveness of gram positive bacteri̇a isolated from American foulbrood suspect bee (apis mellifera) and bee products, with genetic di̇versity of paenibacillus larvae isolates

In this study, it was aimed to determine the characterization of Gram-positive bacteria which were isolated from bee and bee products suspected the American Foulbrood disease, their susceptibility to antibiotics and the genetic diversity of Paenibacillus larvae isolates. In addition to the physical and biochemical properties of 64 isolates, the 16S rRNA gene sequences were used for molecular identification and species identification of the isolates were performed. The isolates were identified at species level as Paenibacillus larvae (18 isolates), P. dentriformis (15 isolates), P. alvei (1 isolate), Bacillus subtilis (8 isolates), B. pumilus (3 isolates), B. licheniformis (2 isolates), B. amyloliquefaciens (1 isolate) and Staphylococcus warneri (3 isolates). Ten isolates were identified Bacillus sp. and two isolates were identified as Kocuria sp. at genus level. It was determined that 54 of the 63 isolates (86%) used in this study were found to be resistant to at least one of the antibiotics used. It was found that 38 isolates (60%) were resistant to two or more antibiotics used and had multiple resistance. On the other hand, the rep-PCR DNA fingerprinting method was used to determine the genetic diversity of the identified Paenibacillus larvae isolates via BOX A1R and MBO REP1 primers. According to the rep-PCR results, it was determined that 8 of 18 isolates (53%) were Ab genotype, 7 (39%) were Ab, 2 (11%) were AB and 1 (6%) was ab genotype. It was determined that each of 18 P. larvae isolates used in the study contained 1 plasmid DNA. At the same time, tet(K), tet(L), tet(M) and tet(W) genes were screened using plasmid DNAs as templete DNA in 8 P. larvae isolates which were resistant to tetracycline and oxytetracycline and the tet(W) gene was detected in 7 isolates while tet(M) gene was detected in 8 isolates. 2017, 101 pages Keywords: American Foulbrood, Paenibacillus larvae, rep-PCR DNA fingerprinting, tetracycline resistance genes.