Microbial contamination control in bioprocessing

A method for microbial contamination control in bioprocessing or improving industrial fermentation hygiene, the method comprising operating a bioreactor comprising a cultured cell expressing a cytoplasmic chlorite dismutase (cCld) sufficient to increase chlorite resistance of the cell, and chlorite sufficient to substantially inhibit growth of one or more contaminating microorganisms in the bioreactor yet permissive to, and not substantially inhibitory of, growth of the cell, wherein the cCld is engineered from a wild-type to lack a functional N-terminal translocation peptide, which results in an inability of the cell to translocate the cCld from the cell cytoplasm into the periplasm, with chlorite sufficient to substantially inhibit growth of the one or more contaminating microorganisms in the bioreactor yet not substantially inhibit growth of the cell, to achieve microbial contamination control in bioprocessing or improving industrial fermentation hygiene, wherein the cCld comprises a mutation that inhibits signal peptide processing or translocation through the inner membrane, comprising one or more point or deletion mutations within residues 2-31 of the cCld, that is a point mutation that is alanine to aspartate at residue 21 of the cCld (A21D).