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2004 Annual Science Report

Pennsylvania State University Reporting  |  JUL 2003 – JUN 2004

Examinations of the Microbial Diversity Found in Ice Cores

4 Institutions
3 Teams
0 Publications
0 Field Sites
Field Sites

Project Progress

Our project designed for Penn State Astrobiology Research Center (PSARC) emphasis is the investigation of microorganisms deposited over 100,000 years ago in the basal portion of a Greenland glacier (GISP2) ice core. Research with this ice core serves as a model for the severe conditions, such as cold temperatures, nutrient and oxygen limitations, desiccation, pressure, etc. that could exist extra terrestrially. Detecting and isolating microorganisms surviving these conditions is important to NASA’s future exploration for life elsewhere, especially in light of the recent exciting results from Mars. Of particular interest was the discovery in the melted ice of many ultra-small cells that would have been excluded by filtration through the 0.2-micron pore size filters used to concentrate cells for microbial diversity studies. Because this finding is significant to detecting microorganisms in all environments, including extraterrestrial habitats, one of our ongoing projects includes developing methods for examining and identifying these ultra-small cells. Dr. Miteva, in my research program, has used several methods for examining these cells including: repeated enrichments for small cells by successive filtrations followed by cultivation in different media, optimizating flow cytometry protocols for analyzing the numbers, size, and viability of cells in ice core samples, and the diversity studies using both extracted DNA and isolate characterization. Of special interest are isolates where the cells remain small during cultivation and that appear distantly related to other known isolates.

    Jean Brenchley Jean Brenchley
    Unspecified Role
    Objective 2.1
    Mars exploration

    Objective 5.1
    Environment-dependent, molecular evolution in microorganisms

    Objective 5.2
    Co-evolution of microbial communities

    Objective 5.3
    Biochemical adaptation to extreme environments

    Objective 6.2
    Adaptation and evolution of life beyond Earth