Johnson (6-5, 245) has spent the past four seasons (2008-11) with the Cincinnati Bengals, playing primarily on special teams and as a backup linebacker. He played in all 16 regular-season games each year with the Bengals and had a career-best 83 tackles in 2008. Johnson was originally drafted by the Arizona Cardinals in the fifth round (142nd overall) of the 2006 NFL Draft out of Louisville. He played special teams in his two seasons with the Cardinals.
Katula (6-6, 265) previously spent time with the Baltimore Ravens, New England Patriots and Minnesota Vikings over the course of his seven-year NFL career. He has appeared in 93 games as a long snapper, but only 13 games over the last two seasons. After being released by the Patriots prior to the start of the 2011 season, Katula spent the last five games of 2011 with the Vikings. Originally signed by the Ravens as an undrafted free agent in 2005, Katula played collegiately at the University of Wisconsin.
The Steelers have placed wide receiver Connor Dixon on their Waived/Injured List and also released tight end Wes Lyons.