BACTERIAL IDENTIFICATION FRO ENVIRONMENTAL SAMPLES BY PHOSPHOLIPID FATTY ACID ANALYSIS

RESEARCH ON IN-SITU REMEDIATION OF SUBSURFACE POLLUTION AND HAZARDOUS WASTES INCLUDES STUDIES ON THE IDENTIFICATION OF BACTERIA IN SUCH SITES. THE ORIGINS, DISTRIBUTIONS, AND RELATIONSHIPS TO ENVIRONMENTAL CONDITIONS ARE FACILITATED BY LEARNING THE IDENTITY OF THE BACTERIA PRESENT IN THE SITES. HIGHLY DESIRABLE WOULD BE THE IDENTIFICATION OF ORGANISMS DIRECTLY FROM THE SOIL WITHOUT THE NECESSITY OF GETTING THE ORGANISMS INTO PURE CULTURE. PHASE I WILL EXPLORE THE USE OF SUPERCRITICAL FLUID EXTRACTION OF BACTERICAL LIPIDS DIRECTLY FROM SOIL SAMPLES, FOLLOWED BY DERIVITIZATION AND GAS CHROMATOGRAPHIC ANALYSIS. USE OF THE ELECTRON CAPTURE DETECTOR WITH FLUORO ESTERS WILL PROVIDE ENHANCED SENSITIVITY FOR DETECTION OF RELATIVELY SMALL NUMBERS OF ORGANISMS. THE RESULTING COMPLEX MIXTURE OF FATTY ACIDS WILL BE STUDIED USING BIOMARKER FATTY ACIDS (COMPOUNDS UNIQUE TO A LIMITED CLASS OF ORGANISMS) TO IDENTIFY MAJOR SPECIES COMPONENTS OF THE MIXED POPULATION. ANOTHER ALGORITHM WILL THEN USE THE BIOMARKER INFORMATION TO SET UP A MATRIX OF POSSIBLE SPECIES COMBINATIONS AND COMPARE THE RESULTS OF THE MATRIX TO THE COMPLEX PROFILE. THIS SHOULD MAKE POSSIBLE REASONABLE ESTIMATES OF THE PERCENTAGE COMPOSITION OF EACH OF THE MAJOR BACTERIAL SPECIES IN A COMPLEX CONSORTIUM.