Fig. (1) Alignment of full length Halobacterium MCM protein. Amino acid sequence alignment of five archaeal MCM helicases: Halobacterium sp. NRC-1, S. solfataricus, T. acidophilum, M. thermautotrophicus, and A. fulgidus. Highlighted residues are conserved in all five proteins. The long inserted sequence found in Halobacterium sp. NRC-1 is the intein.