title: Method for radiorespirometric detection of bacteria in pure culture and in blood.
abstract: Methods are described for the detection of low numbers of bacteria by monitoring (14)CO(2) evolved from (14)C-labeled substrates. Cell suspensions are filtered with membrane filters, and the filter is then moistened with 0.1 ml of labeled medium in a small, closed apparatus. Evolved (14)CO(2) is collected with Ba(OH)(2)-moistened filter pads and assayed with conventional radioactivity counting equipment. The kinetics of (14)CO(2) evolution are shown for several species of bacteria. Fewer than 100 colony-forming units of most species tested were detected in 2 h or less. Bacteria were inoculated into blood and the mixture was treated to lyse the blood cells. The suspension ws filtered and the filter was placed in a small volume of labeled medium. The evolved (14)CO(2) was trapped and counted. A key development in the methodology was finding that an aqueous solution of Rhyozyme and Triton X-100 produced lysis of blood but was not detrimental to bacteria.
mesh_terms: D001419:Bacteria / Q000302:isolation & purification* / Q000378:metabolism; D001431:Bacteriological Techniques; D002245:Carbon Dioxide / Q000096:biosynthesis; D002250:Carbon Radioisotopes; D003937:Diagnosis, Differential; D005069:Evaluation Studies as Topic; D005561:Formates / Q000378:metabolism; D005942:Gluconates / Q000378:metabolism; D005947:Glucose / Q000378:metabolism; D005998:Glycine / Q000378:metabolism; D006461:Hemolysis; D006801:Humans; D008722:Methods; D008851:Micropore Filters; D010447:Peptide Hydrolases; D018805:Sepsis / Q000175:diagnosis*; D013045:Species Specificity; D013501:Surface-Active Agents; D013997:Time Factors
chemical_list: D002250:Carbon Radioisotopes; D005561:Formates; D005942:Gluconates; D013501:Surface-Active Agents; D002245:Carbon Dioxide; D010447:Peptide Hydrolases; D005947:Glucose; D005998:Glycine