Biochemical characterization of the organohalide respiration complex in Dehalococcoides mccartyi strain CBDB1 [article]

Katja Seidel, Technische Universität Berlin, Lorenz Adrian
2020
Halogenated organic compounds of anthropogenic origin are often classified as environmental pollutants due to their strong persistence. However, microbial degradation or transformation has been described for many of the anthropogenic organohalides and biotechnological processes have been developed to use the responsible organisms for bioremediation at contaminated field sites. Bacteria of the class Dehalococcoidia are known to biodegrade many different halogenated organic compounds and they are
more » ... already used for bioremediation. These bacteria are able to breath with halogenated organic compounds by using them as terminal electron acceptor. Respiration with organohalogens is termed organohalide respiration and the key enzyme in this process is a membrane-bound reductive dehalogenase (RdhA). Investigation of the pure culture Dehalococcoides mccartyi strain CBDB1 recently described the reductive dehalogenase as subunit of a higher molecular weight complex, termed 'organohalide respiration' (OHR) complex. This study focused on the study of subunit composition of the OHR complex, the mass spectrometric detection of integral membrane proteins, especially the small integral membrane protein RdhB, predicted to anchor the reductive dehalogenase (RdhA) in the membrane, and attempts to shield light into the stoichiometry of participating subunits. Furthermore protein-protein interactions within the complex were quantitatively analysed to obtain information about the topology and interaction strengths. Structural predictions in combination with experimental data were used to obtain insights into structure-function relationship. For improvement in detection of integral membrane proteins several strategies mainly involving solubilisation, membrane shaving, small protein resolving gels followed by mass spectrometric analysis and top-down mass spectrometry were applied. The most promising techniques were membrane shaving and small protein resolving gels in combination with solubilisation. With these methods several peptides of te [...]
doi:10.14279/depositonce-10565 fatcat:nglsastblrct7ey6jvbrzwpooe