Fig. 7

The inter-ring salt bridge between R452 and E461. a A view of inter-ring salt bridge between R452 and E461 in GroEL. b Structural alignment of Cpn60α and Cpn60β subunits from four organisms. The four organisms are Chlamydomonas reinhardtii (Cr), Oryza sativa (Os), Physcomitrella patens (Pp), and Arabidopsis thaliana (At). Cpn60 sequences are aligned with MultAlin and Espript. Position 461 was indicated by arrows. c Functional complementation of GroEL by coexpression of CPN60β1 with CPN60α/mutant. The experiments were performed as described in Fig. 1d. The coexpression of CPN60β1, CPN60α/mutant, and GroES was induced with 1 mM IPTG in GroEL-deficient E. coli strain MGM100. The strains were grown on medium supplemented with glucose and IPTG at 37 °C for 15 hours