I'm not sure if this is a relevant question for this site, but here is my answer. Kinases are enzymes that carry out the transfer of a phosphate group from a donor molecule to an acceptor molecule. They are a subclass of phosphotransferases, which are a more general group of enzymes that catalyze the transfer of one or more phosphate groups, so no, you cannot take your statement as a fact. There are proteins that phosphorylate that are phosphotransferases but not kinases.

Probably not the forum where that question sound be asked. Try BioForum (http://www.protocol-online.org/forums/index.php?)