title: Resistance of nanobacteria isolated from urinary and kidney stones to broad-spectrum antibiotics.
abstract: OBJECTIVE
  Nanoscopic life forms called Nanobacteria or calcifying nanoparticles (CNP) are unconventional agents. These novel organisms are very small (0.1 to 0.5 microns) and possess unusual properties such as high resistance to heat and routine antimicrobial agents. Nanobacteria are 100 times smaller than bacteria and protected by a shell of apatite, so they could be as candidate for emerging and progress of in vivo pathological calcification. In this study, the inhibitory effect of broad-spectrum antibiotics on growth of these new forms of life has been investigated.
  
  
  METHODS
  Powdered urinary and kidney stones were demineralized with HCl and neutralized with appropriate buffers and became filtered. Finally suspension was incubated in DMEM medium with Fetal Bovine Serum (FBS) and broad-spectrum antibiotics (100U/ml for penicillin and 100μg/ml for streptomycin) for 60 days.
  
  
  RESULTS
  In the presence of broad-spectrum antibiotics, Scanning Electron Micrographs (SEM) showed a spherical shape of these nanobacteria. Also, Energy Dispersive X-ray spectroscopy (EDS) showed a pick for calcium and phosphor. Transmission Electron Microscopy (TEM) results illustrated cover around the nanobacteria.
  
  
  CONCLUSIONS
  The growth of calcifying nanoparticles after adding the broad-spectrum antibiotics may be due to their apatite hard shells supporting them against penetration of the antibiotics.
authors: Department of Biology, Faculty of Science, Ferdowsi University of Mashhad, Mashhad, Iran.
authors: Hadi
authors: H
authors: Sardarabadi
authors: Department of Biology, Faculty of Science, Ferdowsi University of Mashhad, Mashhad, Iran.
authors: Mansour
authors: M
authors: Mashreghi
authors: Biotechnology Research Center, Mashhad University of Medical Sciences, Mashhad, Iran ; Yazd University, Yazd, Iran.
authors: Khadijeh
authors: K
authors: Jamialahmadi
authors: Department of Biology, Faculty of Science, Ferdowsi University of Mashhad, Mashhad, Iran.
authors: Tahere
authors: T
authors: Dianat
keywords: Broad-spectrum antibiotics; Nanobacteria; kidney stones