What are eubacteria classified by?

Eubacteria can be classified by their shapes: spirilla, bacilli, and cocci. These bacteria are prokaryotic, meaning their cells do not have defined nuclei. Researchers at The University of California Santa Barbara call them the "true" bacteria. Some Eubacteria live in places with very little oxygen, and organisms in this kingdom reproduce asexually through binary fission. This can occur as often as once every 20 minutes, contributing to the rapid growth of illnesses, such as strep throat and E. coli. Eubacteria acquire nutrition through three different means: absorption, photosynthesis or chemosynthesis.