Arginine Kinase from the Tardigrade, Macrobiotus occidentalis: Molecular Cloning, Phylogenetic Analysis and Enzymatic Properties Uda, Kouji and Ishida, Mikako and Matsui, Tohru and Suzuki, Tomohiko, Zoological Science, 27, 796-803 (2010), DOI:http://dx.doi.org/10.2108/zsj.27.796