Bacterial sulfite-oxidizing enzymes

Structures and reaction pathways of the molybdenum centres of sulfite-oxidizing enzymes by pulsed EPR spectroscopy.

SOEs (sulfite-oxidizing enzymes) are physiologically vital and occur in all forms of life. During the catalytic cycle, the five-co-ordinate square pyramidal oxo-molybdenum active site passes through the Mo(V) state, and intimate details of the structure can be obtained from variable frequency pulsed EPR spectroscopy through the hyperfine and nuclear quadrupole interactions of nearby magnetic nu...

Implications for the mechanism of sulfite oxidizing enzymes from pulsed EPR spectroscopy and DFT calculations for "difficult" nuclei.

The catalytic mechanisms of sulfite oxidizing enzymes (SOEs) have been investigated by multi-frequency pulsed EPR measurements of "difficult" magnetic nuclei (35.37Cl, 33S, 17O) associated with the Mo(v) center. Extensive DFT calculations have been used to relate the experimental magnetic resonance parameters of these nuclei to specific active site structures. This combined spectroscopic and co...

Sulfite dehydrogenases in organotrophic bacteria : enzymes, genes and regulation

Structural basis of interprotein electron transfer in bacterial sulfite oxidation

Interprotein electron transfer underpins the essential processes of life and relies on the formation of specific, yet transient protein-protein interactions. In biological systems, the detoxification of sulfite is catalyzed by the sulfite-oxidizing enzymes (SOEs), which interact with an electron acceptor for catalytic turnover. Here, we report the structural and functional analyses of the SOE S...

Studies on Bacterial Enzymes

The meningococcus cell contains a peptonase enzyme which hydrolyzes the peptides and similar constituents of commercial "peptone." The activity of this enzyme is independent of the presence of the formed bacterial cell. The peptonase enzyme is more resistant to heat and to oxidation than is the maltase enzyme of the same bacteria.