World's Biggest Bacterium

The special English Word Book says bacteria are small forms of life that can be seen only through a microscope. But that is no longer true. Researchers recently discovered what appears to be the biggest bacterium on earth. The simple, one-celled organism is so big, it can be seen without a microscope. It was first found in a common surgeonfish caught in the Red Sea. Researchers call the bacterium epulopiscium fishelsoni or E. fishelsoni.

Israeli scientists first discovered the organism in 1985. But they believed that what they had found was not a bacterium. They thought that something so big must be an organism containing more than one structure. But Australian scientists recently proved them wrong. They studied the organism's genes to confirm that E. fishelsoni is a one-celled bacterium.