The prokaryotic molecular chaperone, Hsp33, was originally identified as a redox-regulated holding chaperone that is activated upon oxidation, through unfolding in its C-terminal redox-switch domain (RSD). However, NMR analysis of Hsp33 from E. coli in its chaperone-inactive, reduced state (RHsp33) revealed that the protein can bind to a translational elongation factor, EF-Tu. This unexpected intermolecular interaction was critically mediated via the RSD of RHsp33 and the G-domain of EF-Tu. It was also supported by several biochemical and biophysical analysis including NMR that the RHsp33 binding to EF-Tu evokes subsequent unfolding and aggregation of EF-Tu. Therefore, we initiated a small-scale of proteomic screening to search for other potential clients of RHsp33. In particular, NMR screening was highly efficient to recognize weak or fuzzy interaction that is not detectable by biochemical methods such as pull-down assay and gel-filtration. At present, five different proteins, including EF-G, MetG, DnaK, ProS, and NDK were identified to interact with RHsp33. Although detailed mode and biological implications of those interactions remain to be investigated, the results collectively suggest that the chaperone-inactive RHsp33 might have its own functionality in cells via inter-molecular interactions with diverse client proteins.