Smallest bacteria

The smallest living organisms discovered to date are 'nanobes'. Measuring just 20-150 nanometres across, they were found in sandstone samples from 3-5 km (2-3 miles) beneath the ocean floor by Dr Phillippa Uwins (Australia) and colleagues from the University of Queensland, Queensland, Australia. These organisms are around ten times smaller than the smallest conventional bacteria. The team announced their discovery in 1998.