Further insight into single-ring chaperonins is important since the human hsp60 is now implicated in the onset of a wide variety of diseases including arthritis, cancer, and neurodegenerative disorders (Hansen et al., 2002; Parnas et al., 2009; Ghosh et al., 2010; Campanella et al., 2012; Henderson and Martin, 2013). Here, HSPD1 is linked to arthritic joint disease.