Within the database of all known inteins ([http://www.inteins.com/]), 113 known inteins are present in eukaryotes with minimum length of 138 amino acids and maximum length of 844 amino acids. The first intein was found encoded within the VMA gene of "Saccharomyces cerevisiae". They were later found in fungi (ascomycetes, basidiomycetes, zygomycetes and chytrids) and in diverse proteins as well. A protein distantly related to known inteins containing protein, but closely related to metazoan hedgehog proteins, has been described to have the intein sequence from Glomeromycota. Many of the newly described inteins contain homing endonucleases and some of these are apparently active. The abundance of intein in fungi indicates lateral transfer of intein-containing genes. While in eubacteria and archaea, there are 289 and 182 currently known inteins. Not surprisingly, most intein in eubacteria and archaea are found to be inserted into nucleic acid metabolic protein, like fungi.