Involvement of the respiratory chain of gram-negative bacteria in the reduction of tellurite

The terminal oxidases of the respiratory chain of seven strains of gram-neg ative bacteria were shown to be involved in the reduction of tellurite. The rate of tellurite reduction correlated with the intensity of respiration. The inhibitors of terminal oxidases, carbon monoxide and cyanide, inhibited the reduction of tellurite. In Pseudomonas aeruginosa PAO ML4262 and P. ae ruginosa PAO ML4262 (pBS10), the respiratory chain was found to contain thr ee types of cytochrome c, one of which (the carbon monoxide-binding cytochr ome c) was involved in the reduction of tellurite. Agrobacterium tumefacien s VKM B-1219, P. aeruginosa IBPM B-13, and Escherichia coli G0-102bd(++) ce lls contained oxidases aa(3), bb(3), and bd, respectively. The respiratory chain of other strains contained two oxidases: E. coli DH5 alpha of bb(3)- and bd-type, and Erwinia carotovora VKM B-567 of bo(3)- and bd-type. All th e strains under study reduced tellurite with the formation of tellurium cry stallites. Depending on the position of the active center of terminal oxida ses in the plasma membrane, the crystallites appeared either in the peripla smic space [P. aeruginosa PAO ML4262 and P. aeruginosa PAO ML4262 (pBS10)], or on the outer surface of the membrane (il. tumefaciens VKM B-1219 and P. aeruginosa IBPM B-13), its inner surface (E. coli G0-102bd++), or on both surfaces (E. coli DH5a and E. carotovora VKM B-567).