This dataset has been used to establish GroEL-SIP, coupling a targeted proteotyping approach for assessing bacterial community compositions using the taxonomic marker protein GroEL with stable isotope probing to link the identified taxa to substrate assimilation. This dataset contains raw data of four experiments: 1.) Pure cultures of T. aromatica cultivated with 13C or 12C benzoate mixed in defined ratios. 2.) Pure cultures of P. putida cultivated with 13C or 12C benzoate mixed in a 1:1 ratio. 3.) Pure cultures of E. coli cultivated with 12C acetate and 13C or 12C benzoate mixed in a 1:1 ratio. 4.) Co-cultivated biculture of T. aromatica and P. putida cultivated with 13C or 12C benzoate and mixed in a 1:1 ratio. 5.) Co-cultivated biculture of T. aromatica and E. coli cultivated with 12c acetate and 13C or 12C benzoate and mixed in a 1:1 ratio. 1)-3) were analyzed after in-solution digestion 4)-5) were analyzed after in-gel digestion of the 60 kDa band