INVOLVEMENT OF THE CELL-MEMBRANE IN CHEMILUMINESCENCE PATTERNS FROM BACTERIAL CULTURES

Complex liquid media for cultivation of microorganisms show in contact with air, a well detectable chemiluminescence (CL) due to auto-oxidat ion, that is efficiently quenched by bacterial cells growing in it. We report on a similar quenching by membrane preparations of Escherichia coli and Bacillus subtilis. This quenching can be canceled by the add ition of sodium dodecyl sulfate (SDS). SDS also cancels partially the quenching caused by whole cells of all Gram-positive strains, that wer e examined, already from concentrations of 0.02% on. The quenching by whole cells of Gram-negative strains, with the exception of Proteus vu lgaris, is not affected even at SDS concentrations of 2%. The effects are similar with Triton X-100, the degree of cancellation being more s train-specific. The sensitivity of the quenching for detergents may, t hus, be useful for taxonomic identification. (C) 1998 Elsevier Science S.A. All rights reserved.