title: Isolation and Characterization of a Hybrid Respiratory Supercomplex Consisting of Mycobacterium tuberculosis Cytochrome bcc and Mycobacterium smegmatis Cytochrome aa3.
abstract: Recently, energy production pathways have been shown to be viable antitubercular drug targets to combat multidrug-resistant tuberculosis and eliminate pathogen in the dormant state. One family of drugs currently under development, the imidazo[1,2-a]pyridine derivatives, is believed to target the pathogen's homolog of the mitochondrial bc1 complex. This complex, denoted cytochrome bcc, is highly divergent from mitochondrial Complex III both in subunit structure and inhibitor sensitivity, making it a good target for drug development. There is no soluble cytochrome c in mycobacteria to transport electrons from the bcc complex to cytochrome oxidase. Instead, the bcc complex exists in a "supercomplex" with a cytochrome aa3-type cytochrome oxidase, presumably allowing direct electron transfer. We describe here purification and initial characterization of the mycobacterial cytochrome bcc-aa3 supercomplex using a strain of M. smegmatis that has been engineered to express the M. tuberculosis cytochrome bcc. The resulting hybrid supercomplex is stable during extraction and purification in the presence of dodecyl maltoside detergent. It is hoped that this purification procedure will potentiate functional studies of the complex as well as crystallographic studies of drug binding and provide structural insight into a third class of the bc complex superfamily.
authors: From the State University of New York Upstate Medical University, Syracuse, New York 13210.
authors: Mi-Sun
authors: MS
authors: Kim
authors: the Institut Pasteur Korea, Sampyeong-dong, Seongnam-si, Gyeonggi-do 463-400, Korea, and.
authors: Jichan
authors: J
authors: Jang
authors: the Lee Kong Chian School of Medicine and School of Biological Sciences, Nanyang Technological University, Singapore 639798, Singapore.
authors: Nurlilah Binte
authors: NB
authors: Ab Rahman
authors: the Institut Pasteur Korea, Sampyeong-dong, Seongnam-si, Gyeonggi-do 463-400, Korea, and the Lee Kong Chian School of Medicine and School of Biological Sciences, Nanyang Technological University, Singapore 639798, Singapore.
authors: Kevin
authors: http://orcid.org/0000-0003-0297-0150
authors: K
authors: Pethe
authors: From the State University of New York Upstate Medical University, Syracuse, New York 13210, berrye@upstate.edu.
authors: Edward A
authors: http://orcid.org/0000-0001-8929-0259
authors: EA
authors: Berry
authors: From the State University of New York Upstate Medical University, Syracuse, New York 13210, berryl@upstate.edu.
authors: Li-Shar
authors: LS
authors: Huang
mesh_terms: D001426:Bacterial Proteins / Q000737:chemistry* / Q000302:isolation & purification; D004579:Electron Transport; D014450:Electron Transport Complex III / Q000737:chemistry* / Q000302:isolation & purification; D003576:Electron Transport Complex IV / Q000737:chemistry* / Q000302:isolation & purification; D006801:Humans; D009164:Mycobacterium Infections / Q000382:microbiology*; D020102:Mycobacterium smegmatis / Q000737:chemistry*; D009169:Mycobacterium tuberculosis / Q000737:chemistry*
chemical_list: D001426:Bacterial Proteins; D003576:Electron Transport Complex IV; D014450:Electron Transport Complex III
keywords: Mycobacterium smegmatis; Mycobacterium tuberculosis; Q203; cytochrome bcc; electron transfer complex; enzyme purification; respiratory chain; respiratory supercomplex