A Blue Native-PAGE analysis of membrane protein complexes in Clostridium thermocellum
1 State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, PR China
2 Department of physiology and Biophysics, School of Medicine, Virginia Commonwealth University, 1101 East Marshall Street, Richmond, VA 23298, USA
BMC Microbiology 2011, 11:22 doi:10.1186/1471-2180-11-22Published: 26 January 2011
Clostridium thermocellum is a Gram-positive thermophilic anaerobic bacterium with the unusual capacity to convert cellulosic biomass into ethanol and hydrogen. Identification and characterization of protein complexes in C. thermocellum are important toward understanding its metabolism and physiology.
A two dimensional blue native/SDS-PAGE procedure was developed to separate membrane protein complexes of C. thermocellum. Proteins spots were identified by MALDI-TOF/TOF Mass spectrometry. 24 proteins were identified representing 13 distinct protein complexes, including several putative intact complexes. Interestingly, subunits of both the F1-F0-ATP synthase and the V1-V0-ATP synthase were detected in the membrane sample, indicating C. thermocellum may use alternative mechanisms for ATP generation.
Two dimensional blue native/SDS-PAGE was used to detect membrane protein complexes in C. thermocellum. More than a dozen putative protein complexes were identified, revealing the simultaneous expression of two sets of ATP synthase. The protocol developed in this work paves the way for further functional characterization of these protein complexes.